https://en.wikipedia.org/wiki/Wikipedia:WikiProject_Medicine/Translation_task_force/RTT/Simple_AIDS
{{Infobox disease
| Name = HIV/AIDS
| Image = Red_Ribbon.svg
| Caption = [[紅絲帶]]是愛滋病毒帶原者以及愛滋病患的[[有機團結|團結]]象徵。
| Alt = A red ribbon in the shape of a bow
| Width = 120
| DiseasesDB = 5938
| ICD10 = {{ICD10|B|20 || b|20}} – {{ICD10|B|24 || b|20}}
| ICD9 = {{ICD9|042}}-{{ICD9|044}}
| ICDO =
| OMIM = 609423
| MedlinePlus = 000594
| eMedicineSubj = emerg
| eMedicineTopic = 253
| MeshID = D000163
}}
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Human immunodeficiency virus infection and acquired immune deficiency syndrome (HIV/AIDS) is a spectrum of conditions caused by infection with the human immunodeficiency virus (HIV).[1][2][3] Following initial infection, a person may experience a brief period of influenza-like illness. This is typically followed by a prolonged period without symptoms. As the infection progresses, it interferes more and more with the immune system, making the person much more susceptible to common infections like tuberculosis, as well as opportunistic infections and tumors that do not usually affect people who have working immune systems. The late symptoms of the infection are referred to as AIDS. This stage is often complicated by an infection of the lung known as pneumocystis pneumonia, severe weight loss, a type of cancer known as Kaposi’s sarcoma, or other AIDS-defining conditions.
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’’’人類免疫缺乏病毒’’’（俗稱’’’愛滋病毒’’’，{{lang-en|human immunodeficiency virus, HIV}}）’’’感染及後天免疫缺乏症候群’’’（{{lang-en|acquired immune deficiency syndrome, AIDS}}，音譯’’’愛滋病’’’）屬於同一病毒感染後兩種不同的病程表現[1][2][3]。初次感染[[人類免疫缺陷病毒|愛滋病毒]]後，可能會有短暫{{Link-en|類流感|Influenza-like illness}}的症狀，之後進入長時間無症狀的潛伏期。隨著病毒在體內不斷地複製感染，患者的免疫系統受到破壞，逐漸成為許多病原體的攻擊目標，如常見的[[結核|結核菌]]感染、[[機會性感染|伺機性感染]]和特定[[腫瘤]]等後期多樣化的臨床症狀，一般免疫系統正常者通常不易罹患。感染愛滋病毒的晚期患者，稱為後天免疫缺乏症候群（AIDS，愛滋病）。後天免疫不全症候群的定義感染症（{{Link-en|AIDS-defining clinical condition|AIDS-defining conditions}}）最常見的包括[[惡病體質|嚴重的體重減輕]]、[[肺囊蟲肺炎]]（{{lang-en|Pneumocystis pneumonia}}）、[[卡波西氏肉瘤]]（{{link-en|Karposi’s sarcoma}}）等。
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HIV is transmitted primarily via unprotected sexual intercourse (including anal and oral sex), contaminated blood transfusions,hypodermic needles, and from mother to child during pregnancy, delivery, or breastfeeding.[4] Some bodily fluids, such as saliva and tears, do not transmit HIV.[5] Prevention of HIV infection, primarily through safe sex and needle-exchange programs, is a key strategy to control the spread of the disease. There is no cure or vaccine; however, antiretroviral treatment can slow the course of the disease and may lead to a near-normal life expectancy. While antiretroviral treatment reduces the risk of death and complications from the disease, these medications are expensive and have side effects. Without treatment, the average survival time after infection with HIV is estimated to be 9 to 11 years, depending on the HIV subtype.[6]
<!--傳染途徑與預防 -->
愛滋病毒主要經由[[安全性行為|不安全性行為]]{{link-en|傳播|Transmission_(medicine}}（包含[[肛交]]與[[口交]]）、受污染的[[輸血]]、{{link-en|針扎感染|Hypodermic_needle}}、{{link-en|母子垂直感染|Vertically_transmitted_infection}}（經由{{link-en|懷孕|HIV_and_pregnancy}}、生產或哺乳）[4]。某些體液（如唾液及淚水）不會傳染愛滋病毒[5]。預防並控制愛滋病毒傳播的關鍵策略，主要包含[[安全性行為]]及{{link-en|使用乾淨針具|Needle_exchange_programme}}。目前尚無治癒愛滋病的方法或{{link-en|疫苗|HIV_vaccine}}，不過接受抗病毒治療的患者有望減緩病程，平均剩餘壽命有接近健康人的可能。[[抗反轉錄病毒藥物|抗病毒藥物]]雖可降低死亡與併發症之風險，但要價高昂且有副作用。未接受治療的患者平均餘命受病毒亞型影響，約在 9~11 年間[6]。
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Genetic research indicates that HIV originated in west-central Africa during the late nineteenth or early twentieth century.[7] AIDS was first recognized by the United States Centers for Disease Control and Prevention (CDC) in 1981 and its cause—HIV infection—was identified in the early part of the decade.[8] Since its discovery, AIDS has caused an estimated 36 million deaths worldwide (as of 2012).[9] In 2013 it resulted in about 1.34 million deaths.[10] As of 2012, approximately 35.3 million people are living with HIV globally.[9] HIV/AIDS is considered a pandemic—a disease outbreak which is present over a large area and is actively spreading.[11]
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{{Link-en|基因研究|Molecular phylogenetics}}指出愛滋病毒起源於19世紀末或20世紀初的非洲中西部[7]。1981年，[[美國疾病控制與預防中心|美國疾病管制局]]（ {{lang-en|Centers for Disease Control and Prevention,CDC}}）首次發現愛滋病，於 1980 年代早期發現其病因：HIV病毒感染[8]。愛滋病至今已造成全世界3600萬人死亡（統計至2012年止）[9]；2013年約134萬人因病死亡[10]。根據2012年統計，全球約有3530萬愛滋病毒帶原者[9]。愛滋病被視為一種[[瘟疫|大流行]]--爆發於廣大區域，易於傳播[11]。
HIV/AIDS has had a great impact on society, both as an illness and as a source of discrimination. The disease also has significant economic impacts. There are many misconceptions about HIV/AIDS such as the belief that it can be transmitted by casual non-sexual contact. The disease has also become subject to many controversies involving religion. It has attracted international medical and political attention as well as large-scale funding since it was identified in the 1980s.[12]
愛滋病對社會影響甚鉅，不只是一種疾病跟歧視{{Link-en|歧視|Discrimination against people with HIV/AIDS}}的根源，在經濟層面{{Link|損耗|Economic impact of HIV/AIDS}}影響也很大。社會上也有許多對愛滋病的誤解{{Link-en|誤解|Misconceptions about HIV/AIDS}}，例如愛滋病可經一般接觸傳播，而非性交途徑；愛滋病亦引起許多爭議，在宗教{{Link-en|宗教|Religion and HIV/AIDS}}界亦然。自愛滋病被發現的 1980 年代以來，持續得到各國醫療界與政治界的關注及大規模資金投入[12]。
There are three main stages of HIV infection: acute infection, clinical latency and AIDS.[13][14]
感染愛滋病毒後，病程分為三個階段：急性感染期、臨床潛伏期以及後天免疫缺乏症候群（或稱：發病期）[13][14]。
Acute infection
The initial period following the contraction of HIV is called acute HIV, primary HIV or acute retroviral syndrome.[13][15] Many individuals develop an influenza-like illness or a mononucleosis-like illness 2–4 weeks post exposure while others have no significant symptoms.[16][17] Symptoms occur in 40–90% of cases and most commonly include fever, large tender lymph nodes,throat inflammation, a rash, headache, and/or sores of the mouth and genitals.[15][17] The rash, which occurs in 20–50% of cases, presents itself on the trunk and is maculopapular, classically.[18] Some people also develop opportunistic infections at this stage.[15] Gastrointestinal symptoms such as nausea, vomiting or diarrhea may occur, as may neurological symptoms of peripheral neuropathy or Guillain-Barre syndrome.[17] The duration of the symptoms varies, but is usually one or two weeks.[17]
Due to their nonspecific character, these symptoms are not often recognized as signs of HIV infection. Even cases that do get seen by a family doctor or a hospital are often misdiagnosed as one of the many common infectious diseases with overlapping symptoms. Thus, it is recommended that HIV be considered in people presenting an unexplained fever who may have risk factors for the infection.[17]
===急性感染期===
人類免疫缺乏病毒進入人體初期，病毒快速繁殖，每毫升血液中的病毒含量可達數百萬，稱為急性HIV感染（英文：acute HIV, primary HIV或acute retroviral syndrome）[13][15]。大多數病例（40-90%）在感染後二到四周，會產生{{Link-en|類似流感|Influenza-like illness}}或者[[傳染性單核白血球增多症|單核血球增多症]]的症狀，常見包括[[發熱|發燒]]、{{Link-en|淋巴結腫痛|Lymphadenopathy}}、{{Link-en|喉嚨發炎|Pharyngitis}}、[[疹|皮疹]]、頭痛、生殖器瘡或[[鵝口瘡]]。此外，10%以上的愛滋病感染者，不會出現急性感染期的症狀[15][16][17]。20-50%的病例，典型症狀為分布在軀幹及上肢之紅色無痛性{{Link-en|斑丘疹|Maculopapular rash}[18]。某些患者在此時期也會出現[[機會性感染|伺機性感染]][15]。其他的症狀如：腸胃症狀，包含噁心、嘔吐或[[腹瀉]]、神經症狀，包含{{Link-en|末梢神經病變|Peripheral neuropathy}}或[[吉巴氏綜合症]]（{{lang-en|Guillain-Barré syndrome}}）[17]；持續時間因人而異，多於一至二週內發生。因感染愛滋病毒的症狀無特異性，其他常見的傳染病亦有相似症狀，故這些症狀無法作為確診愛滋病毒感染的依據。為提高病患急性感染期的診斷率，建議高危險群在不明原因發燒的情況下，接受進一步檢驗[17]。以下為愛滋病感染者出現急性症狀的比例[中1]：
* 發熱 80%
* 嗜睡和全身不適 70%
* 肌肉痛和關節痛 50 - 70 %
* 淋巴結腫大 40 - 70 %
* 盜汗 50%
* 胃腸炎 50 - 70 %
* 腹瀉 30%
* 口腔潰瘍 10 - 30 %
* 神經性頭痛 40 - 70 %
* 皮疹 40 - 80 %
* 生殖器潰瘍 5 - 15 %
* 血小板減少 45%
* 白細胞減少 40%
* 轉氨酶上升 20%
Clinical latency
The initial symptoms are followed by a stage called clinical latency, asymptomatic HIV, or chronic HIV.[14] Without treatment, this second stage of the natural history of HIV infection can last from about three years[19] to over 20 years[20] (on average, about eight years).[21] While typically there are few or no symptoms at first, near the end of this stage many people experience fever, weight loss, gastrointestinal problems and muscle pains.[14] Between 50 and 70% of people also develop persistent generalized lymphadenopathy, characterized by unexplained, non-painful enlargement of more than one group of lymph nodes (other than in the groin) for over three to six months.[13]
Although most HIV-1 infected individuals have a detectable viral load and in the absence of treatment will eventually progress to AIDS, a small proportion (about 5%) retain high levels of CD4+ T cells (T helper cells) without antiretroviral therapy for more than 5 years.[17][22] These individuals are classified as HIV controllers or long-term nonprogressors(LTNP).[22] Another group is those who also maintain a low or undetectable viral load without anti-retroviral treatment who are known as "elite controllers" or "elite suppressors". They represent approximately 1 in 300 infected persons.[23]
===臨床潛伏期===
急性症狀後，由於免疫系統抑制病毒活動，並減少血液中的病毒數量，病人進入愛滋病臨床潛伏期，又稱為無症狀HIV、慢性HIV帶原[14]。潛伏期長度受很多因素的影響，在未接受治療的情況下，受到愛滋病毒感染後，其{{Link-en|自然病史進展|Natural history of disease}}在臨床潛伏期最短可能僅有兩周，亦可長達3年[19]至20年以上[20]，平均約8年[21]。潛伏初期的感染者幾乎無症狀，多數患者在後期出現發燒、體重下降、腸胃道不適及肌肉疼痛等現象[14]。其中有50-70%患者發展為{{Link-en|持續性全身性淋巴腺病變|Persistent generalized lymphadenopathy}}（英文：persistent generalized lymphadenopathy），特徵為超過一個淋巴結群（鼠蹊部除外）無痛性腫大且原因不明，時間達3至6個月[13]。
大部分受到{{Link-en|HIV-1愛滋病毒|Subtypes of HIV}}感染者，未接受治療的情況下，在患者的血液中均可偵測到病毒，且隨著病程進展至愛滋病（AIDS）。然而小部分（約5%）的感染者在未經反轉錄酶藥物治療下，仍能持續5年以上維持高數量CD4+ 輔助T 細胞（[輔助型T細胞），醫學將其歸類為HIV控制者（英文：controllers）或{{Link-en|長期不發展者|Long-term nonprogressor}}（{{link-en|long-term nonprogressors, LTNP}}）[17][22]。更少部分（約每300名患者中有1 名）稱為「非凡控制者」（{{link-en|"elite controllers"或"elite suppressors"}}）[註1]的病患在未經反轉錄酶藥物治療下仍能維持極低至偵測不到的病毒量[23]。
Acquired immunodeficiency syndrome
Acquired immunodeficiency syndrome (AIDS) is defined in terms of either a CD4+ T cell count below 200 cells per µL or the occurrence of specific diseases in association with an HIV infection.[17] In the absence of specific treatment, around half of people infected with HIV develop AIDS within ten years.[17] The most common initial conditions that alert to the presence of AIDS are pneumocystis pneumonia (40%), cachexia in the form of HIV wasting syndrome (20%) and esophageal candidiasis.[17] Other common signs include recurring respiratory tract infections.[17]
Opportunistic infections may be caused by bacteria, viruses, fungi and parasites that are normally controlled by the immune system.[24] Which infections occur partly depends on what organisms are common in the person’s environment.[17] These infections may affect nearly every organ system.[25]
People with AIDS have an increased risk of developing various viral induced cancers including Kaposi’s sarcoma, Burkitt’s lymphoma, primary central nervous system lymphoma and cervical cancer.[18] Kaposi’s sarcoma is the most common cancer occurring in 10 to 20% of people with HIV.[26] The second most common cancer is lymphoma which is the cause of death of nearly 16% of people with AIDS and is the initial sign of AIDS in 3 to 4%.[26] Both these cancers are associated with human herpesvirus 8.[26] Cervical cancer occurs more frequently in those with AIDS due to its association with human papillomavirus(HPV).[26] Conjunctival cancer (of the layer which lines the inner part of eyelids and the white part of the eye) is more common in those with HIV.[27]
Additionally, people with AIDS frequently have systemic symptoms such as prolonged fevers, sweats (particularly at night), swollen lymph nodes, chills, weakness, and unintended weight loss.[28] Diarrhea is another common symptom present in about 90% of people with AIDS.[29] They can also be affected by diverse psychiatric and neurological symptoms independent of opportunistic infections and cancers.[30]
===後天免疫缺乏症候群===
後天免疫缺乏症候群（AIDS）定義為每[[微升]]（10<sup>−6</sup> L）血液中CD4+ 輔助T細胞低於200個；或在愛滋病毒感染後，出現用來診斷是否感染的特定臨床症狀（{{Link-en|AIDS-defining clinical condition|AIDS-defining conditions}}）[17]。若未給予特殊治療，近半數的愛滋病毒感染者，將於10年內進展為愛滋病（AIDS）[17]，此階段的病患，一般不會存活超過九個月；然因醫學持續進步，存活時間也可能延長。下列情況為最初發病的可能徵兆，包括{{肺囊蟲肺炎]]（40%）、[[惡病體質|愛滋病毒消耗性症候群]]（{{lang-en|HIV wasting syndrome}}）（20%）以及{{Link-en|食道念珠菌症|Esophageal candidiasis}}[17]。其他常見徵象包含：反覆發生{{Link-en|呼吸道感染|Respiratory tract infection}}[17]。
[[機會性感染|伺機性感染]]指的是，正常人身體健康時幾乎不會感染的[[細菌]]、[[病毒]]、[[真菌]]或[[寄生蟲]]，因免疫系統失常，開始入侵並感染人體，造成疾病[24]；至於會發生何種伺機性感染，則取決於病患所暴露的周遭環境[17]。在免疫缺乏的情況下，幾乎全身各[[生物系統|系統器官]]都可能遭受伺機性感染[25]。
愛滋病患者容易罹患和病毒有關的腫瘤，其風險相較一般人為高，諸如[[卡波西氏肉瘤]]、{{Link-en|Burkitt淋巴瘤|Burkitt’s lymphoma}}、{{Link-en|原發性中樞神經系統淋巴瘤|Primary central nervous system lymphoma}}等[18]。卡波西氏肉瘤為愛滋病患族群中最常見的腫瘤，約佔10-20%[26]；其次常見的腫瘤為淋巴瘤，佔了約16%的愛滋病患者死因，且有3-4%左右的愛滋病患者以淋巴瘤為最初病發的病徵[26]。這些腫瘤皆由{{Link-en|人類皰疹病毒第8型|Kaposi’s sarcoma-associated herpesvirus}}所引起[26]。愛滋病毒感染後，另一種常見的癌症為[[結膜]]癌[27]。
此外，愛滋病患者經常出現全身性的症狀，例如：長時間的發熱、盜汗（夜間尤是）、淋巴結腫大、畏寒、無力感和[[惡病體質|非預期的體重減輕][28]，腹瀉亦是另一常見的病徵，約有90%的愛滋病患者會產生腹瀉症狀[29]。愛滋病患者也可能出現無法以伺機性感染和腫瘤解釋的精神或神經症狀[30]。
HIV is transmitted by three main routes: sexual contact, exposure to infected body fluids or tissues, and from mother to child during pregnancy, delivery, or breastfeeding (known as vertical transmission).[4] There is no risk of acquiring HIV if exposed to feces, nasal secretions, saliva, sputum, sweat, tears, urine, or vomit unless these are contaminated with blood.[33] It is possible to be co-infected by more than one strain of HIV—a condition known as HIV superinfection.[38]
愛滋病毒主要透過以下三種方式傳播：[[人類性行為|性行為]]、體液接觸（接觸帶有病毒的體液或組織）、{{Link-en|垂直傳染|Vertically transmitted infection}}（母親經由懷孕、生產或哺乳傳染給嬰兒）[4]。目前相信接觸[[糞便]]、鼻腔分泌物、唾液、{{Link-en|痰|Sputum}}、汗液、眼淚、尿液或嘔吐物不會有感染愛滋病毒的風險，除非接觸到的是遭受患者血液汙染[33]的分泌物。而遭到兩種不同亞型的愛滋病毒{{Link-en|重複感染|Coinfection}}[38]是有可能的，稱之為{{Link-en|愛滋病毒的重複感染（英文：HIV superinfection）|HIV superinfection}}。
===性行為感染===
Sexual
The most frequent mode of transmission of HIV is through sexual contact with an infected person.[4] The majority of all transmissions worldwide occur through heterosexual contacts (i.e. sexual contacts between people of the opposite sex);[4] however, the pattern of transmission varies significantly among countries. In the United States, as of 2009, most sexual transmission occurred in men who had sex with men,[4] with this population accounting for 64% of all new cases.[39]
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性行為傳播
目前最常見的傳染途徑是與感染者進行非安全性行為，目前全球多數[4]的愛滋感染係發生於[[異性戀|異性間性行為}，然而不同國家的傳染形式差異甚大，例如 2009 年美國主要的性行為傳染形式係為[[男男性接觸人群|男性間的性行為]]，佔全體新病例中的64%[4][39]。
With regard to unprotected heterosexual contacts, estimates of the risk of HIV transmission per sexual act appear to be four to ten times higher in low-income countries than in high-income countries.[40] In low-income countries, the risk of female-to-male transmission is estimated as 0.38% per act, and of male-to-female transmission as 0.30% per act; the equivalent estimates for high-income countries are 0.04% per act for female-to-male transmission, and 0.08% per act for male-to-female transmission.[40] The risk of transmission from anal intercourse is especially high, estimated as 1.4–1.7% per act in both heterosexual and homosexual contacts.[40][41] While the risk of transmission from oral sex is relatively low, it is still present.[42] The risk from receiving oral sex has been described as "nearly nil";[43]however, a few cases have been reported.[44] The per-act risk is estimated at 0–0.04% for receptive oral intercourse.[45] In settings involving prostitution in low income countries, risk of female-to-male transmission has been estimated as 2.4% per act and male-to-female transmission as 0.05% per act.[40]
<!--危險族群-->
單次不[[安全性行為]]感染愛滋病毒的機率，與性行為形式、性別及感染者體內病毒量有關。根據統計，低所得國家感染愛滋的風險較高所得國家高了四至十倍[40]。在低所得國家，女性感染者將病毒傳染給男性的機率約0.38%，而男性感染者傳染給女性的機率約0.30%；相較於此，高所得國家分別為0.04%及0.08%[40]。不論是同性或異性間，肛交風險較陰道交為高，約1.4-1.7%[40][41]。[[口交]]感染愛滋病毒的機率低於無套陰道交及肛交[42]，雖然有一些感染案例，接受口交的一方的感染危險性仍被描述為"接近零"，單次行為感染危險性約莫在 0-0.04%。目前認為每次口交接受者感染的機率約在0-0.04%[45]。在低收入國家的[[性交易|性工作者]]族群中，單次性行為女性傳染給男性的比例達 2.4%，男性傳染給女性的比率為 0.05%[40]。
Risk of transmission increases in the presence of many sexually transmitted infections[46] and genital ulcers.[40] Genital ulcers appear to increase the risk approximately five fold.[40] Other sexually transmitted infections, such as gonorrhea, chlamydia, trichomoniasis, and bacterial vaginosis, are associated with somewhat smaller increases in risk of transmission.[45]
The viral load of an infected person is an important risk factor in both sexual and mother-to-child transmission.[47] During the first 2.5 months of an HIV infection a person’s infectiousness is twelve times higher due to this high viral load.[45] If the person is in the late stages of infection, rates of transmission are approximately eight fold greater.[40]
<!--增加風險的因素 -->
若同時存在其他[[性傳播疾病|性病]]，如[[淋病]]、{{Link-en|衣原體|Chlamydia infection}}、[[滴蟲性陰道炎|滴蟲]]或[[細菌性陰道病|陰道細菌感染]]，會些許提高愛滋病毒感染的風險[45][46]；如果同時有{{Link-en|生殖器潰瘍|Genital ulcer}}，愛滋感染的風險更提高約五倍[40]。
不論是性行為或母子垂直傳播，感染者體內的{{Link-en|病毒濃度|Viral load}}，都是感染風險的關鍵因素[47]。甫受到愛滋病毒感染的前2.5個月，由於體內高濃度的病毒量，患者傳染能力將提高12倍[45]。於愛滋病後期，免疫系統瓦解時，會導致病毒量再次提升，患者感染力因而提高8倍以上[40]。
Commercial sex workers (including those in pornography) have an increased rate of HIV.[48][49] Rough sex can be a factor associated with an increased risk of transmission.[50] Sexual assault is also believed to carry an increased risk of HIV transmission as condoms are rarely worn, physical trauma to the vagina or rectum is likely, and there may be a greater risk of concurrent sexually transmitted infections.[51]
性工作者（包含{{Link-en|色情影片演員|STDs in the porn industry}}）感染愛滋病毒的比例，有增加的趨勢[48][49]。粗暴而不安全的性行為（如[[BDSM|性虐遊戲]]）可能會增加愛滋傳染的風險[50]。同樣的，[[性侵犯|性侵害]]案件中，由於保險套甚少使用，陰道或直腸損傷增加，以及同時存在其它性病的可能性增高，以上皆可能讓愛滋病毒傳播機率大幅提高[51]。
Body fluids
The second most frequent mode of HIV transmission is via blood and blood products.[4] Blood-borne transmission can be through needle-sharing during intravenous drug use, needle stick injury, transfusion of contaminated blood or blood product, or medical injections with unsterilised equipment. The risk from sharing a needle during drug injection is between 0.63 and 2.4% per act, with an average of 0.8%.[52] The risk of acquiring HIV from a needle stick from an HIV-infected person is estimated as 0.3% (about 1 in 333) per act and the risk following mucous membrane exposure to infected blood as 0.09% (about 1 in 1000) per act.[33] In the United States intravenous drug users made up 12% of all new cases of HIV in 2009,[39] and in some areas more than 80% of people who inject drugs are HIV positive.[4]
===體液感染===
第二常見的愛滋病毒感染途徑，是經由血液及血液製品[4]。血液感染可能透過共享針頭進行毒品靜脈注射、遭針頭刺傷、輸入受到感染的血液或血液製品、或使用未消毒完全的設備進行藥物注射。因單次共用針頭{{link-en|毒品注射|drug injection}}發生感染的風險，在0.63%到2.4%之間，平均0.8%[52]。單次遭愛滋病毒感染的針頭扎傷而感染的機率預估為0.3%（每333次當中有1次感染），而透過[[黏膜]]接觸到含愛滋病毒的血液，其感染風險約0.09%（每1000次當中有1次感染）[33]。2009年根據美國統計，毒品靜脈注射占該年愛滋病毒新案例的12%[39]，而在某些區域，超過80%的毒品靜脈注射族群愛滋檢驗為陽性[4]。
<!--輸血-->
HIV is transmitted in about 93% of blood transfusions using infected blood.[52] In developed countries the risk of acquiring HIV from a blood transfusion is extremely low (less than one in half a million) where improved donor selection and HIV screening is performed;[4] for example, in the UK the risk is reported at one in five million[53] and in the United States it was one in 1.5 million in 2008.[54] In low income countries, only half of transfusions may be appropriately screened (as of 2008),[55] and it is estimated that up to 15% of HIV infections in these areas come from transfusion of infected blood and blood products, representing between 5% and 10% of global infections.[4][56]
輸入遭愛滋病毒感染的血液製品其感染率高達93%[52]。在已發展國家，由於血液捐贈來源的管控加上[[HIV檢測|愛滋病毒篩檢]]的實施，因[[輸血]]而感染愛滋病毒的機率極低，少於五十萬分之一[4]。在2008年，英國因輸血而感染愛滋病毒的風險為五百萬分之一[53]，而美國則為一百五十萬分之一[54]。相較之下在低所得國家，由於[[HIV檢測|愛滋病毒篩檢]]僅能涵蓋約一半的血液製品[55]，估計當地有15%的愛滋病毒感染來自[[輸血]]，同時占了全球愛滋病毒感染人數的5%至10%[4][56]。
<!--針具使用 -->
Unsafe medical injections play a significant role in HIV spread in sub-Saharan Africa. In 2007, between 12 and 17% of infections in this region were attributed to medical syringe use.[57] The World Health Organization estimates the risk of transmission as a result of a medical injection in Africa at 1.2%.[57] Significant risks are also associated with invasive procedures, assisted delivery, and dental care in this area of the world.[57]
People giving or receiving tattoos, piercings, and scarification are theoretically at risk of infection but no confirmed cases have been documented.[58] It is not possible for mosquitoes or other insects to transmit HIV.[59]
在{{Link-en|撒哈拉以南非洲的愛滋病患者|HIV/AIDS in Africa}}，多半是因為不安全的藥物注射方式而感染到愛滋病毒。在2007年，當地因為使用醫療注射筒造成的愛滋病毒傳染，占12到17%[57]。世界衛生組織估計，在非洲因藥物注射方式被感染愛滋病毒的機率約為1.2%[57]。除此之外，在當地進行侵入性治療、輔助性生產或牙齒保健，都很有可能會被感染[57]。
理論上，不論幫人進行或是本身接受[[刺青]]、[[身體穿洞|穿環]]、{{Link-en|疤痕紋身|Scarification}}，都有被愛滋病毒感染的風險，不過目前沒有證實的案例[58]。藉由[[蚊|蚊子]]或是其他昆蟲，是不可能傳染愛滋病毒的[59]。
===母子垂直傳染===
HIV can be transmitted from mother to child during pregnancy, during delivery, or through breast milk.[60][61] This is the third most common way in which HIV is transmitted globally.[4] In the absence of treatment, the risk of transmission before or during birth is around 20% and in those who also breastfeed 35%.[60] As of 2008, vertical transmission accounted for about 90% of cases of HIV in children.[60] With appropriate treatment the risk of mother-to-child infection can be reduced to about 1%.[60] Preventive treatment involves the mother taking antiretroviral during pregnancy and delivery, an elective caesarean section, avoiding breastfeeding, and administering antiretroviral drugs to the newborn.[62] Antiretrovirals when taken by either the mother or the infant decrease the risk of transmission in those who do breastfeed.[63] Many of these measures are however not available in the developing world.[62] If blood contaminates food during pre-chewing it may pose a risk of transmission.[58]
愛滋病毒會從母親經懷孕、分娩與哺乳等途徑傳染給小孩[60][61]，此為全球常見愛滋病毒感染原因中的第三位[4]。在缺乏治療的情形下，經懷孕或分娩而傳染的風險約為20%，如果再加上哺乳，則會增高至35%。截至2008年，兒童愛滋病毒感染，有90%來自母子垂直傳染[60]。在適當的預防性醫療處置下，母子垂直傳染的風險可降低至約1%[60]，包括懷孕及分娩時服用反轉錄酶藥物、選擇性[[剖宮產|剖腹產]]、避免哺乳，以及給予新生兒反轉錄酶藥物[62]。在哺乳無法避免的情況下（如嬰兒營養來源不足），母親或嬰兒服用反轉錄酶藥物皆可降低愛滋病毒藉由哺乳傳染的機率[63]。遺憾的是，目前許多發展中國家，沒有能力提供前述預防性醫療處置[62]。此外，若愛滋帶原的母親口腔內有傷口，在不經意之下將{{Link-en|咀嚼後|Premastication}}的食物哺餵嬰兒，愛滋病毒可能藉由血液汙染食物，而造成感染的風險[58]。
{{Main|HIV}}
[[File:HIV-virion-structure en.svg|thumb|upright=1.2|Diagram of a HIV virion structure]]
HIV is the cause of the spectrum of disease known as HIV/AIDS. HIV is a retrovirus that primarily infects components of the human immune system such as CD4+ T cells, macrophages and dendritic cells. It directly and indirectly destroys CD4+ T cells.[65]
人體感染愛滋病毒後，從無症狀帶原者，到後天免疫缺乏症候群出現，擁有多樣化的病程表現。愛滋病毒屬於[[逆轉錄病毒|反轉錄病毒（英文：retrovirus）]]，主要感染人體[[免疫系統|免疫細胞]]如CD4+ 輔助T細胞、[[巨噬細胞]]以及[[樹狀細胞|樹突細胞]]。此病毒尤其會直接或間接摧毀CD4+ 輔助T細胞[65]。
HIV is a member of the genus Lentivirus,[66] part of the family Retroviridae.[67] Lentiviruses share many morphological and biological characteristics. Many species of mammals are infected by lentiviruses, which are characteristically responsible for long-duration illnesses with a long incubation period.[68] Lentiviruses are transmitted as single-stranded, positive-sense, enveloped RNA viruses. Upon entry into the target cell, the viral RNA genome is converted (reverse transcribed) into double-stranded DNA by a virally encoded reverse transcriptase that is transported along with the viral genome in the virus particle. The resulting viral DNA is then imported into the cell nucleus and integrated into the cellular DNA by a virally encoded integrase and host co-factors.[69] Once integrated, the virus may become latent, allowing the virus and its host cell to avoid detection by the immune system.[70]Alternatively, the virus may be transcribed, producing new RNA genomes and viral proteins that are packaged and released from the cell as new virus particles that begin the replication cycle anew.[71]
愛滋病毒分類學上[[屬 (生物)|屬]]於[[慢病毒屬]]（英文：genus Lentivirus）[66]，為[[逆轉錄病毒|反轉錄病毒]]科家族的一員[67]。慢病毒屬彼此間擁有眾多[[形態學 (生物學)|型態]]及[[生物學]]相似的特徵。許多種類的慢病毒，在感染了哺乳動物之後，都有病程緩慢且[[疾病潛伏期|潛伏期]]長的特徵[68]。慢病毒以具有套膜的[[義 (分子生物學)|正]]單股[[核醣核酸病毒|RNA病毒}}顆粒型式傳播。病毒顆粒內除了有[[核醣核酸|RNA]][[基因組]]外，尚帶有反轉錄酶（英文：reverse transcriptase）及整合酶（英文：integrase）。因此當病毒顆粒進入了目標細胞後，病毒的[[核醣核酸|RNA]][[基因組|基因]]會藉[[逆轉錄酶|反轉錄酶]]協助，反轉錄成雙股[[去氧核醣核酸|DNA]]。接著由[[整合酶]]及宿主細胞內的輔因子，將此雙股[[去氧核醣核酸|DNA]]嵌入宿主的DNA中[69]。一旦病毒˙的基因訊息嵌入宿主[[去氧核醣核酸|DNA]]之中，會被視為[[疾病潛伏期|潛伏]]於宿主細胞內，可避免被免疫系統發現[70]。然而，潛伏的病毒仍可以重新[[轉錄]]，製造出新的病毒[[核醣核酸|RNA]]及和病毒相關的蛋白質，用蛋白外殼集中包裹起來，接著釋放出宿主細胞外，藉此感染新的宿主細胞，進行下一個感染週期[71]。
Two types of HIV have been characterized: HIV-1 and HIV-2. HIV-1 is the virus that was originally discovered (and initially referred to also as LAV or HTLV-III). It is more virulent, more infective,[72] and is the cause of the majority of HIV infections globally. The lower infectivity of HIV-2 as compared with HIV-1 implies that fewer people exposed to HIV-2 will be infected per exposure. Because of its relatively poor capacity for transmission, HIV-2 is largely confined to West Africa.[73]
目前已知有{{Link-en|兩種愛滋病毒|Subtypes of HIV}}：HIV-1和HIV-2。HIV-1是最早發現的病毒類型（起初亦被稱為LAV或HTLV-III）。相較於HIV-2，HIV-1的[[病毒性|致命性]]更強，{{Link-en|感染力|Infectivity}}更[72]，目前也是占全球愛滋感染人口中多數的病毒株。HIV-2傳染力較低，目前感染HIV-2的患者主要集中於[[西部非洲|西非]]地區[73]。
{{Main|Pathophysiology of HIV/AIDS}}
[[File:HIV-budding-Color.jpg|thumb|alt=A large round blue object with a smaller red object attached to it. Multiple small green spots are speckled over both.|[[Scanning electron micrograph]] of HIV-1, colored green, budding from a cultured [[lymphocyte]].]]
After the virus enters the body there is a period of rapid viral replication, leading to an abundance of virus in the peripheral blood. During primary infection, the level of HIV may reach several million virus particles per milliliter of blood.[74] This response is accompanied by a marked drop in the number of circulating CD4+ T cells. The acute viremia is almost invariably associated with activation of CD8+ T cells, which kill HIV-infected cells, and subsequently with antibody production, or seroconversion. The CD8+ T cell response is thought to be important in controlling virus levels, which peak and then decline, as the CD4+ T cell counts recover. A good CD8+ T cell response has been linked to slower disease progression and a better prognosis, though it does not eliminate the virus.[75]
愛滋病毒最初侵入人體時，由於{{Link-en|病毒複製|Viral replication}}迅速，使得患者呈現{{Link-en|病毒血症|Viremia}}的症狀，其血液中病毒濃度極高，每毫升的血液中可含有數百萬顆病毒[74]。此時血液中CD4+ 輔助T細胞數量急遽下降，另一方面[[細胞毒性T細胞|CD8+ 胞殺T細胞]]活化，試圖摧毀受病毒感染的細胞，隨後體內產生抗愛滋病毒抗體，稱為{{Link-en|血清轉換（英文：seroconversion）|Seroconversion}}。[[細胞毒性T細胞|CD8+ 胞殺T細胞]]在體內控制愛滋病毒感染中扮演重要角色，能夠使急性期病毒數量從高峰開始下降，而CD4+ 輔助T細胞數量回升。研究證實，快速而有效的[[細胞毒性T細胞|CD8+ 胞殺T細胞]]活化和延緩疾病進程以及較好的預後相關，儘管如此仍無法完全清除愛滋病毒[75]。
Ultimately, HIV causes AIDS by depleting CD4+ T cells. This weakens the immune system and allows opportunistic infections. T cells are essential to the immune response and without them, the body cannot fight infections or kill cancerous cells. The mechanism of CD4+ T cell depletion differs in the acute and chronic phases.[76] During the acute phase, HIV-induced cell lysis and killing of infected cells by cytotoxic T cells accounts for CD4+ T cell depletion, although apoptosis may also be a factor. During the chronic phase, the consequences of generalized immune activation coupled with the gradual loss of the ability of the immune system to generate new T cells appear to account for the slow decline in CD4+ T cell numbers.[77]
隨著病程進展，[[輔助T細胞|CD4+ 輔助T細胞]耗盡、免疫系統瓦解，最終導致[[機會性感染|伺機性感染]]，稱為愛滋病。免疫反應中，T細胞是不可或缺的，若缺乏則無法對抗感染或殺死癌細胞。CD4+ 輔助T細胞數量下降的機制，在急性期與慢性期是不同的[76]。在急性期，主要由愛滋病毒引起的細胞溶解，以及CD8+[[細胞毒性T細胞|胞殺T細胞]]殺死受感染細胞，另外[[細胞凋亡]]也可能是原因之一。在慢性期，全面免疫活化伴隨產生新T細胞的能力逐漸流失，導致CD4+ 輔助T細胞的數目慢慢漸少[77]。
Although the symptoms of immune deficiency characteristic of AIDS do not appear for years after a person is infected, the bulk of CD4+ T cell loss occurs during the first weeks of infection, especially in the intestinal mucosa, which harbors the majority of the lymphocytes found in the body.[78] The reason for the preferential loss of mucosal CD4+ T cells is that the majority of mucosal CD4+ T cells express the CCR5 protein which HIV uses as a co-receptor to gain access to the cells, whereas only a small fraction of CD4+ T cells in the bloodstream do so.[79] A specific genetic change that alters the CCR5 protein when present in both chromosomes very effectively prevents HIV-1 infection.[80]
雖然從感染愛滋病毒至臨床上出現愛滋病病徵，需要數年時間，但在感染初期數週即有大量的CD4+輔助T細胞死亡，特別是位於小腸黏膜，該處是人體內富有淋巴球的組織之一[˙78]。大部分小腸黏膜CD4+輔助T細胞會表現出一種稱為{{link-en|CCR5|CCR5}}的表面蛋白，這是一種幫助愛滋病毒成功辨認並且進入T細胞的{{link-en|輔助受體|Co-receptor}}。相較之下，血液中的CD4+輔助T細胞僅有小部分帶有{{link-en|CCR5|CCR5}}，這也是小腸黏膜CD4+輔助T細胞會最先被病毒攻擊的原因[79]。有研究指出，如果CCR5基因在成對[[染色體]]皆發生特定的突變，其T細胞將可有效地避免被愛滋病毒感染[80]。
HIV seeks out and destroys CCR5 expressing CD4+ T cells during acute infection.[81] A vigorous immune response eventually controls the infection and initiates the clinically latent phase. CD4+ T cells in mucosal tissues remain particularly affected.[81] Continuous HIV replication causes a state of generalized immune activation persisting throughout the chronic phase.[82] Immune activation, which is reflected by the increased activation state of immune cells and release of pro-inflammatory cytokines, results from the activity of several HIV gene products and the immune response to ongoing HIV replication. It is also linked to the breakdown of the immune surveillance system of the gastrointestinal mucosal barrier caused by the depletion of mucosal CD4+ T cells during the acute phase of disease.[83]
愛滋病毒在急性期會尋找並摧毀表現CCR5的CD4+ 輔助T細胞[81]。活化的免疫反應最終控制了感染，而之後便進入潛伏期。然而在黏膜組織的CD4+ 輔助T細胞仍然受影響[81]。愛滋病毒的持續複製，在慢性期導致免疫系統全面並持續地活化[82]。免疫活化反映在免疫細胞活化的增加、促發炎的[[細胞因子|細胞激素]]的釋放，導因於愛滋病毒[[基因產物]]的活性以及針對病毒複製的持續免疫反應。此外，CD4+ 輔助T細胞的減少，不論是急性或慢性期，主要發生在腸胃道黏膜屏障[83]。
HIV/AIDS is diagnosed via laboratory testing and then staged based on the presence of certain signs or symptoms.[16] HIV screening is recommended by the United States Preventive Services Task Force for all people 15 years to 65 years of age including all pregnant women.[88] Additionally testing is recommended for all those at high risk, which includes anyone diagnosed with a sexually transmitted illness.[19] In many areas of the world a third of HIV carriers only discover they are infected at an advanced stage of the disease when AIDS or severe immunodeficiency has become apparent.[19]
診斷愛滋病毒感染必須藉由血液檢驗確立，接著根據{{link-en|臨床徵象及症候|AIDS-defining clinical condition}}判斷病患在病程何種階段[16]。{{link-en|美國預防服務工作小組|United States Preventive Services Task Force}}建議15歲以上至65歲（含孕婦）均接受愛滋病毒初步篩檢[88]。若為高風險族群（包括已知有其它性傳染疾病者），則建議進一步接受其他檢驗[19]。在許多區域，約有三分之一的帶原者，在疾病晚期時才被發現感染愛滋病毒[19]。
===HIV testing愛滋病毒檢驗===
Most people infected with HIV develop specific antibodies (i.e. seroconvert) within three to twelve weeks of the initial infection.[18] Diagnosis of primary HIV before seroconversion is done by measuring HIV-RNA or p24 antigen.[18] Positive results obtained by antibody or PCR testing are confirmed either by a different antibody or by PCR.[16]
大部份人感染愛滋病毒後，會在3至12周內產生特定[[抗體]]，此階段又稱（如{{link-en|血清抗體轉陽|Seroconversion}}） ，亦即可藉由儀器偵測血清[[抗體]]而診斷愛滋病毒感染[18]。而在血清抗體尚未產生之前，診斷僅能藉由偵測愛滋病毒的遺傳因子-[[核醣核酸|RNA]]或病毒顆粒表面的{{link-en|殼蛋白-p24|P24 capsid protein}}抗原[18]。根據台灣疾病管制署針對，成人愛滋病毒感染確診必須符合下列條件之一[中2]：（一）、抗體篩檢檢測，包括酵素免疫法（Enzyme immunoassay，EIA）、顆粒凝集法（Particle agglutination，PA）或抗原/抗體複合型檢測（HIV antibody and antigen combination assay）陽性，再經西方墨點法（Western blot）檢驗，確認為陽性反應者。若使用坊間常見快速檢測法檢測陽性者，仍需進行前述兩種檢測。（二）、分子生物學核酸檢測，即經由[[聚合酶鏈式反應|聚合酶連鎖反應（Polymerase chain reaction/PCR）]]測試後呈陽性反應者。（三）、愛滋病毒抗原p24篩檢陽性，且進行中和試驗（Neutralization test, NT），確認為陽性反應者。
Antibody tests in children younger than 18 months are typically inaccurate due to the continued presence of maternal antibodies.[89] Thus HIV infection can only be diagnosed by PCR testing for HIV RNA or DNA, or via testing for the p24 antigen.[16] Much of the world lacks access to reliable PCR testing and many places simply wait until either symptoms develop or the child is old enough for accurate antibody testing.[89] In sub-Saharan Africa as of 2007–2009 between 30 and 70% of the population was aware of their HIV status.[90] In 2009, between 3.6 and 42% of men and women in Sub-Saharan countries were tested[90] which represented a significant increase compared to previous years.[90]
小於18個月之幼兒，體內帶有來自{{link-en|母體的抗體|Passive immunity}}，使用前述抗體篩檢檢測會產生偽陽性之結果[89]，故只能選擇[[聚合酶鏈式反應|PCR]]或{{link-en|殼蛋白-p24|P24 capsid protein}}抗原檢測法[16]。大部分的地區缺乏可靠的[[聚合酶鏈式反應|PCR]]檢測技術，因此新生兒疑似愛滋個案只能等到一定年紀使用抗體檢測，甚至等到症狀出現方能確診[89]。根據2007至2009年在愛滋病盛行區--薩哈拉沙漠以南非洲國家的調查，30%至70%的人口開始關注自身愛滋病毒感染狀態，同時3.6%至42%的人口得以接受愛滋病毒的檢測[90]，此一比率相較於過往已顯著提高[90]。
===Classification病程分級系統===
Two main clinical staging systems are used to classify HIV and HIV-related disease for surveillance purposes: the WHO disease staging system for HIV infection and disease,[16] and the CDC classification system for HIV infection.[91] The CDC’s classification system is more frequently adopted in developed countries. Since the WHO’s staging system does not require laboratory tests, it is suited to the resource-restricted conditions encountered in developing countries, where it can also be used to help guide clinical management. Despite their differences, the two systems allow comparison for statistical purposes.[14][16][91]
人體受到愛滋病毒後的病程發展與{{link-en|疾病監控|Disease surveillance}}，在臨床上較被廣泛使用的分類方法，是由兩個不同的單位所發展出來的：1. 由{{link-en|世界衛生組織所撰寫的愛滋病毒感染病程分期系統|WHO disease staging system for HIV infection and disease}}[16]；2. 由{{link-en|美國疾病控制與預防中心所撰寫的愛滋病毒感染的病程分期系統|CDC classification system for HIV infection}}[91]。在發展中的國家，較常採用由美國疾病控制與預防中心所撰寫的分期系統。而自從世界衛生組織的愛滋病分期系統公布後，由於不需要實驗室的檢測結果即可進行分類，相較於前者，更適合用於開發中國家或是在醫療環境較不充裕的環境下使用。僅管此二系統間有些許差異，但都可以利用統計的方式進行愛滋病的分析[14][16][91]。
The World Health Organization first proposed a definition for AIDS in 1986.[16] Since then, the WHO classification has been updated and expanded several times, with the most recent version being published in 2007.[16] The WHO system uses the following categories:
世界衛生組織在1986年首次定義了愛滋病[16]。自那時以來，該組織持續不斷地更新對於此疾病的分類系統，最近一次的更新在2007年[16]。世界衛生組織現行的愛滋病毒感染病程分期系統如下：
The United States Center for Disease Control and Prevention also created a classification system for HIV, and updated it in 2008 and 2014.[91][92] This system classifies HIV infections based on CD4 count and clinical symptoms, and describes the infection in five groups.[92] In those greater than six years of age it is:[92]
For surveillance purposes, the AIDS diagnosis still stands even if, after treatment, the CD4+ T cell count rises to above 200 per µL of blood or other AIDS-defining illnesses are cured.[14]
而[[美國疾病控制與預防中心]]對於愛滋病病情的分類系統，分別在2008年和2014年出現了兩次的更新[91][92]。同時藉由CD+4輔助T細胞的數量以及臨床症狀進行分類[92]。
以疾病監控的目的來說，愛滋病的診斷與病情分類仍然是有其必要，倘若患者接受治療後，血液中的CD4+輔助T細胞，每微升 (microliter或μL)的數量回升高於200個，或是愛滋病相關的疾病被治癒，即可被認為該治療有效果[14]。
===Sexual contact性行為保護措施===
Consistent condom use reduces the risk of HIV transmission by approximately 80% over the long term.[93] When condoms are used consistently by a couple in which one person is infected, the rate of HIV infection is less than 1% per year.[94] There is some evidence to suggest that female condoms may provide an equivalent level of protection.[95] Application of a vaginal gel containing tenofovir (a reverse transcriptase inhibitor) immediately before sex seems to reduce infection rates by approximately 40% among African women.[96] By contrast, use of the spermicide nonoxynol-9 may increase the risk of transmission due to its tendency to cause vaginal and rectal irritation.[97]
性行為時全程使用[[保險套]]，長期而言，能降低八成的愛滋病毒的傳播[93]。當配偶間有一人感染愛滋病毒，持續地使用保險套，將使愛滋病毒感染率降到每年1%以下[94]。有部分證據顯示，[[女用保險套]]或許也能提供同樣程度的保護力[95]。以非洲的女性為研究族群，其研究發現於性交前，使用含有{{link-en|Tenofovir|Tenofovir}}(一種[[逆轉錄酶抑制劑|反轉錄酶抑制劑]])的陰道潤滑劑有助於降低多達40%的感染率[96]。相反的，如果使用{{link-en|壬基酚聚氧乙烯醚-9(N-9)|Nonoxynol-9}}作為{{link-en|殺精劑|Spermicide}}，可能刺激陰道和肛門部位，反而提高了感染的可能性[97]。
Circumcision in Sub-Saharan Africa "reduces the acquisition of HIV by heterosexual men by between 38% and 66% over 24 months".[98] Based on these studies, the World Health Organization and UNAIDS both recommended male circumcision as a method of preventing female-to-male HIV transmission in 2007.[99] Whether it protects against male-to-female transmission is disputed[100][101] and whether it is of benefit in developed countries and among men who have sex with men is undetermined.[102][103][104] The International Antiviral Society, however, does recommend for all sexually active heterosexual males and that it be discussed as an option with men who have sex with men.[105] Some experts fear that a lower perception of vulnerability among circumcised men may cause more sexual risk-taking behavior, thus negating its preventive effects.[106]
在[[撒哈拉以南非洲|撒哈拉沙漠以南的非洲]]地區進行的研究顯示曾接受[[割禮|包皮環切術]]的異性戀男性，在兩年的追蹤間，感染率為未接受者的38~66%[98]。根據此研究，世界衛生組織和聯合國愛滋病規劃署，一同在2007年將男性包皮環切術，視為避免異性間愛滋病毒傳播的方法之一[99]。但此方法對於預防異性間的感染仍有爭議[100][101]，而且對於[[已開發國家]]，是否能預防[[男男性接觸人群|男同性戀者]]間的傳染也還是不清楚[102][103][104]。無論如何，國際抗病毒社群的確建議，有性生活的異性戀男性接受包皮環切術以防治傳染，對於同性戀男性也應該視為一種防治傳染的選項[105]。但部分專家也擔心，如此是否也會造成接受包皮環切術的男性，低估了感染的風險，更願意嘗試高風險的性行為，從而減弱此方法的預防效果。
Programs encouraging sexual abstinence do not appear to affect subsequent HIV risk.[107] Evidence for a benefit from peer education is equally poor.[108] Comprehensive sexual education provided at school may decrease high risk behavior.[109] A substantial minority of young people continues to engage in high-risk practices despite knowing about HIV/AIDS, underestimating their own risk of becoming infected with HIV.[110] Voluntary counseling and testing people for HIV does not affect risky behavior in those who test negative but does increase condom use in those who test positive.[111] It is not known whether treating other sexually transmitted infections is effective in preventing HIV.[47]
鼓勵{{link-en|禁慾|Abstinence-only sex education}}對於隨後的愛滋病感染率並無影響[107]。{{link-en|健康促進團體|Peer education}}的功效看來也並沒有特別突出的效果[108]。學校提供正確的[[性教育]]，似乎能降低學生去從事高風險性行為[109]。少數年輕人，在未了解愛滋病前，持續地進行高風險性行為，低估自己被感染的風險[111]。目前並不清楚，治療其他性傳染疾病，對於預防愛滋病感染有無成效[47]。
===Pre-exposure暴露前預防性投藥===
Treating people with HIV whose CD4 count ≥ 350 cells/µL with antiretrovirals protects 96% of their partners from infection.[112] This is about a 10 to 20 fold reduction in transmission risk.[113] Pre-exposure prophylaxis (PrEP) with a daily dose of the medications tenofovir, with or without emtricitabine, is effective in a number of groups including men who have sex with men, couples where one is HIV positive, and young heterosexuals in Africa.[96] It may also be effective in intravenous drug users with a study finding a decrease in risk of 0.7 to 0.4 per 100 person years.[114]
Universal precautions within the health care environment are believed to be effective in decreasing the risk of HIV.[115] Intravenous drug use is an important risk factor and harm reduction strategies such as needle-exchange programmes and opioid substitution therapy appear effective in decreasing this risk.[116][117]
使用抗反轉錄病毒藥物，治療CD4+輔助T每微升（microliter或μL）350顆細胞以上的愛滋病病人，能提供96%患者的伴侶免於感染[112]。可降低約10~20倍的傳染風險[113]。在非洲，對於男同性戀者、伴侶中有一人是愛滋病毒感染者和年輕異性戀者，使用{{link-en|Tenofovir|Tenofovir}}(或有(或沒有)加上{{link-en|emtricitabine|Emtricitabine}})作為{{link-en|暴露前預防性投藥|Pre-exposure prophylaxis}}相當有效[96]。此配方可能對於每一百位靜脈藥物使用者，每年也能降低0.7~0.4人感染的可能[114]。
在健康照護環境中，普遍地施行{{link-en|預防性措施|Universal precautions}}，即使用醫用手套、護目鏡或口罩等物品，確實地避免接觸到患者的體液，被認為能有效地降低愛滋病毒傳播的風險[115]。使用{{link-en|靜脈注射|Drug injection}}的方式施打毒品，被認為是傳染愛滋病毒的高風險因子之一，而為了{{link-en|減少|Harm reduction}}因為吸毒反而得到愛滋病的可能性，{{link-en|提供免費的針具|Needle exchange programme}}以及{{link-en|提供較安全的鴉片類麻醉藥品|Opioid replacement therapy}}，是兩個可以減少因為吸毒者因施打毒品反而得到愛滋病的策略[116][117]。。
===Post-exposure暴露後預防性投藥===
A course of antiretrovirals administered within 48 to 72 hours after exposure to HIV-positive blood or genital secretions is referred to as post-exposure prophylaxis (PEP).[118] The use of the single agent zidovudine reduces the risk of a HIV infection five-fold following a needle-stick injury.[118] As of 2013, the prevention regimen recommended in the United States consists of three medications—tenofovir, emtricitabine and raltegravir—as this may reduce the risk further.[119]
PEP treatment is recommended after a sexual assault when the perpetrator is known to be HIV positive, but is controversial when their HIV status is unknown.[120] The duration of treatment is usually four weeks[121] and is frequently associated with adverse effects—where zidovudine is used, about 70% of cases result in adverse effects such as nausea (24%), fatigue (22%), emotional distress (13%) and headaches (9%).[34]
當懷疑或確認接觸到帶有愛滋病毒的血液、體液或生殖器分泌物後的48至72小時內，可以使用抗反轉錄酶藥物進行愛滋病的防治，此一藥物的療程被稱為「{{link-en|暴露後預防性投藥|Post-exposure prophylaxis}} (post-exposure prophylaxis (PEP))」[118]。若是被染有病毒的針頭銳器劃傷，使用後[[齊多夫定|齊多夫定(zidovudine)]]，可以降低被愛滋病毒感染的風險多達五倍[118]。而截至2013年為止，美國提出了利用三種藥物 ({{link-en|Tenofovir|Tenofovirs}}、{{link-en|Emtricitabine|Emtricitabine}}和{{link-en|Raltegravir|Raltegravir}})做為複合性的預防性投藥，被認為或許可以更進一步地降低被傳染的風險[119]。在[[性侵犯|性侵案件]]中，若加害人已確認帶有愛滋病毒，則建議被害人盡速進行「{{link-en|暴露後預防性投藥|Post-exposure prophylaxis}}」，但若不確定加害者是否為愛滋病毒的帶原者，則是否建議被害人使用藥物，此一論點則沒有定論[120]。「{{link-en|暴露後預防性投藥|Post-exposure prophylaxis}}」目前的療程通常為四週[121]，並且已知會伴隨著副作用，以服用[[齊多夫定|齊多夫定(zidovudine)]]為例，約有70%的使用者會有以下的副作用：噁心 (約24%)；乏力 (約22%)；情緒上的困擾 (悲傷、苦惱或憂慮) (約13%)；頭痛 (約9%)[34]。
===Mother-to-child預防母子垂直感染===
Main article: HIV and pregnancy
Programs to prevent the vertical transmission of HIV (from mothers to children) can reduce rates of transmission by 92–99%.[61][116] This primarily involves the use of a combination of antiviral medications during pregnancy and after birth in the infant and potentially includes bottle feeding rather than breastfeeding.[61][122] If replacement feeding is acceptable, feasible, affordable, sustainable, and safe, mothers should avoid breastfeeding their infants; however exclusive breastfeeding is recommended during the first months of life if this is not the case.[123] If exclusive breastfeeding is carried out, the provision of extended antiretroviral prophylaxis to the infant decreases the risk of transmission.[124]
由於{{link-en|母子垂直傳染|Vertically transmitted infection}}是愛滋病傳播的主要途徑之一，因此若母體帶有愛滋病毒，則會建議採取下列的預防措施以避免嬰兒受到傳染，據評估，採取適當的預防措施，能降低92-99%的垂直傳染風險[61][116]。首先在懷孕期間使用複合型的抗病毒藥物，而嬰兒出生後亦須服用藥物；若使用替代品餵食嬰兒是可以被接受的 (經濟、安全性等考量)，則建議使用{{link-en|奶瓶|Baby bottle}}取代[[母乳餵養]][61][122]；若現實層面上只能選用母乳，則僅建議在出生後數個月內餵食母乳[123]。若以母乳餵食嬰兒，則建議持續地使用抗病毒藥物，以降低病毒傳播的風險[124]。
===Vaccination疫苗發展現況===
As of 2012 there is no effective vaccine for HIV or AIDS.[125] A single trial of the vaccine RV 144 published in 2009 found a partial reduction in the risk of transmission of roughly 30%, stimulating some hope in the research community of developing a truly effective vaccine.[126] Further trials of the RV 144 vaccine are ongoing.[127][128]
截至2012年為止，臨床上仍無有效的愛滋病毒[[疫苗]]的產生[125]。2009年時，被稱為「{{link-en|RV 144|RV 144}}」的愛滋病疫苗在臨床測試的結果中發現，能降低30%的傳播病毒風險，此一結果帶給了後續的研究人員更大的希望[126]。而目前接續{{link-en|RV 144|RV 144}}的其他計畫仍在進行中[127][128]。
There is currently no cure or effective HIV vaccine. Treatment consists of highly active antiretroviral therapy (HAART) which slows progression of the disease.[129] As of 2010 more than 6.6 million people were taking them in low and middle income countries.[130]Treatment also includes preventive and active treatment of opportunistic infections.
臨床上目前尚無有效的愛滋病[[疫苗]]。治療包括使用高效能抗反轉錄病毒療法（highly active antiretroviral therapy，HAART），俗稱雞尾酒療法，來減緩病情進程[129]。截至2010年，在中低收入的國家，超過660萬名患者正接受抗反轉錄病毒療法[130]。其它治療包括預防和處理伺機性感染。
===Antiviral therapy抗病毒藥物===
Current HAART options are combinations (or "cocktails") consisting of at least three medications belonging to at least two types, or "classes," of antiretroviral agents.[131] Initially treatment is typically a non-nucleoside reverse transcriptase inhibitor (NNRTI) plus two nucleoside analogue reverse transcriptase inhibitors (NRTIs).[132] Typical NRTIs include: zidovudine (AZT) or tenofovir (TDF) and lamivudine (3TC) or emtricitabine (FTC).[132]Combinations of agents which include a protease inhibitors (PI) are used if the above regimen loses effectiveness.[131]
目前雞尾酒療法（HAART）由至少兩大類[[抗反轉錄病毒藥物]]中挑出三種組合而成[131]。典型藥物組合由一種非核苷酸抗[[逆轉錄酶抑制劑|反轉錄酶抑制劑]]（non-nucleoside reverse transcriptase inhibitor/NNRTI），加上兩種核苷酸抗[[逆轉錄酶抑制劑|反轉錄酶抑制劑]]（nucleoside analogue reverse transcriptase inhibitors/NRTIs）[132]。常見的核苷酸抗[[逆轉錄酶抑制劑|反轉錄酶抑制劑]]有：[[齊多夫定]]（zidovudine/AZT）；{{link-en|tenofovir（TDF）|Tenofovir}}；[[拉米夫定]]（lamivudine/3TC）；{{link-en|emtricitabine（FTC）|Emtricitabine}}[132]。若上述的藥物組合效果不佳，可考慮加入[[蛋白酶抑制劑]]（protease inhibitors/PI）系列的藥物[131]。
When to start antiretroviral therapy is subject to debate.[19][133] The World Health Organization recommends antiretrovirals in all adolescents, adults and pregnant women with a CD4 count less than 500/µl with this being especially important in those with counts less than 350/µl or those with symptoms regardless of CD4 count.[132] This is supported by the fact that beginning treatment at this level reduces the risk of death.[134] The United States in addition recommends them for all HIV-infected people regardless of CD4 count or symptoms; however it makes this recommendation with less confidence for those with higher counts.[105][135] While the WHO also recommends treatment in those who are co-infected with tuberculosis and those with chronic active hepatitis B.[131] Once treatment is begun it is recommended that it is continued without breaks or "holidays".[19] Many people are diagnosed only after treatment ideally should have begun.[19] The desired outcome of treatment is a long term plasma HIV-RNA count below 50 copies/mL.[19] Levels to determine if treatment is effective are initially recommended after four weeks and once levels fall below 50 copies/mL checks every three to six months are typically adequate.[19] Inadequate control is deemed to be greater than 400 copies/mL.[19] Based on these criteria treatment is effective in more than 95% of people during the first year.[19]
開始抗反轉錄病毒藥物治療的時機在醫界仍無定論[19][133]。世界衛生組織建議不論成人、青少年或孕婦，當CD+4輔助T細胞少於每微升350個，或是已經出現愛滋病症狀（不論CD+4輔助T細胞數量多少），則強烈建議開始治療[132]。而CD+4輔助T細胞少於每微升500個，亦可建議開始治療[132]。若愛滋病毒感染合併結核感染或慢性[[B型肝炎]]，亦建議直接進行抗反轉錄病毒藥物治療[131]。目前的證據顯示，開始治療後可降低因愛滋病死亡的風險[134]。另外，美國愛滋病治療指引則建議不論症狀或CD+4輔助T細胞數量，所有愛滋病毒感染者都應接受藥物治療，儘管在CD+4輔助T細胞高於每微升500個的感染者，其治療好處證據較弱[105][135]。
一旦開始治療，則不可以停藥[19]。許多患者的情況，理想上是確診後再進行治療即可[19]。治療後的理想結果，是血漿中的愛滋病毒RNA的複製套數，每毫升少於50套[19]。開始治療後四週，須檢查血漿中的愛滋病毒RNA的複製套數以檢視治療的結果，而一旦血漿中愛滋病毒RNA的複製套數每毫升少於50套，則檢查的週期則可改為每3至6個月檢查一次[19]。倘若檢測後血漿中愛滋病毒RNA的複製套數每毫升多於400套，則代表治療沒有效果[19]。根據上述的規範條件，治療後首年超過95%的患者治療的結果是有效的[19]。
Benefits of treatment include a decreased risk of progression to AIDS and a decreased risk of death.[136] In the developing world treatment also improves physical and mental health.[137] With treatment there is a 70% reduced risk of acquiring tuberculosis.[131] Additional benefits include a decreased risk of transmission of the disease to sexual partners and a decrease in mother-to-child transmission.[131] The effectiveness of treatment depends to a large part on compliance.[19] Reasons for non-adherence include poor access to medical care,[138] inadequate social supports, mental illness and drug abuse.[139] The complexity of treatment regimens (due to pill numbers and dosing frequency) and adverse effects may reduce adherence.[140] Even though cost is an important issue with some medications,[141] 47% of those who needed them were taking them in low and middle income countries as of 2010[130] and the rate of adherence is similar in low-income and high-income countries.[142]
接受治療的優點如下：能夠降低發展成愛滋病的風險；降低因愛滋病和其他併發症死亡的可能性[136]。並且能夠同時提高患者的身體以及心理的健康[137]。也能降低患者同時得到肺結核70%的風險[131]。亦能減少傳播病毒給性伴侶或是母子垂直傳染的機會[131]。
治療的成效仰賴患者是否能夠受到完善的照顧，以及遵照醫囑的服藥遵從性 (定期服用藥物及回診監控病情)[19]。缺乏良好的服藥遵從性的原因通常有：缺乏良好的醫療照護[138]；缺乏社會支持；[[精神病|精神疾病]]的影響以其對於[[物質濫用|藥物的濫用]][139]。而治療本身的複雜度 (藥物的種類、數量、服用的頻率和[[不良反應 (醫學)|副作用]])也影響了患者遵照醫囑的可能性，以及定期回診的意願[140]。
僅管治療的價格成本確實是重要的因素[141]，但在2010年，在中低收入的國家中，仍有約47%的患者接受了藥物的治療，並且高收入國家的患者，遵照良好的服藥遵從性的比例和低收入國家的患者是相似的[142]。
Specific adverse events are related to the antiretroviral agent taken.[143] Some relatively common adverse events include: lipodystrophy syndrome, dyslipidemia, and diabetes mellitus, especially with protease inhibitors.[14] Other common symptoms include diarrhea,[143][144] and an increased risk of cardiovascular disease.[145] Newer recommended treatments are associated with fewer adverse effects.[19] Certain medications may be associated with birth defects and therefore may be unsuitable for women hoping to have children.[19]
Treatment recommendations for children are somewhat different from those for adults. The World Health Organisation recommends treating all children less than 5 years of age; children above 5 are treated like adults.[146] The United States guidelines recommend treating all children less than 12 months of age and all those with HIV RNA counts greater than 100,000 copies/mL between one year and five years of age.[147]
通常治療所引發的副作用，皆為抗反轉錄病毒藥物所引起[143]。一些相對常見的副作用包括：{{link-en|脂質營養不良症候群|HIV-associated lipodystrophy}} (全身性的脂肪組織減少)；{{link-en|血脂異常|Dyslipidemia}}；[[糖尿病]]等，以上可能是由蛋白酶抑制劑的藥物所引起的副作用[14]。其他常見的副作用尚有[[腹瀉]][143][144]，以及罹患心血管疾病的風險增加[145]。目前更新的治療方式皆是以降低副作用為目標[19]。部分藥物可能會導致{{link-en|胎兒生長缺陷|Congenital disorder}}，因此若是計畫生育的婦女，可能需要避免[19]。
兒童的治療方式和成人不同。世界衛生組織的建議是5歲以下的兒童都需要接受治療，而5歲以上的治療方針與成人相同[146]。而美國醫界的建議則是建議1歲以下的幼兒，以及1至5歲的兒童若是血漿中的愛滋病毒RNA的複製套數，每毫升多於100,000套，都需要接受治療[147]。
===Opportunistic infections預防伺機性感染===
Measures to prevent opportunistic infections are effective in many people with HIV/AIDS. In addition to improving current disease, treatment with antiretrovirals reduces the risk of developing additional opportunistic infections.[143] Adults and adolescents who are living with HIV (even on anti-retroviral therapy) with no evidence of active tuberculosis in settings with high tuberculosis burden should receive isoniazid preventive therapy (IPT), the tuberculin skin test can be used to help decide if IPT is needed.[148] Vaccination against hepatitis A and B is advised for all people at risk of HIV before they become infected; however it may also be given after infection.[149]
預防伺機性感染在愛滋治療中佔有重要角色。抗反轉錄病毒的藥物除了壓制病毒複製，也能進一步降低得到伺機性感染的風險[143]。在肺結核盛行的高風險地區，一個愛滋病患者經評估後若無活動性結核病，應該要接受六到九個月肺結核用藥-[[異煙肼]]的預防治療 （isoniazid preventive therapy/IPT）。而在台灣，新感染者均應接受[[結核菌素試驗|結核菌素皮內測試（英文：tuberculin skin test，TST）]]以診斷是否有潛伏性結核感染，並接受預防性治療。然而需注意結核菌素皮內測試在愛滋病人免疫力低下的狀況可能呈現偽陰性，而[[卡介苗]][[疫苗接種|接種]]史則產生偽陽性的結果[註解1][註解2]。愛滋病毒感染高危險群建議事先接種A型及B型[[肝炎]][[疫苗]]，而即使感染後尚未接種者也可考慮接受疫苗的接種[149]。
Trimethoprim/sulfamethoxazole prophylaxis between four and six weeks of age and ceasing breastfeeding in infants born to HIV positive mothers is recommended in resource limited settings.[150] It is also recommended to prevent Pneumocystis pneumonia (PCP) when a person’s CD4 count is below 200 cells/uL and in those who have or have previously had PCP.[151] People with substantial immunosuppression are also advised to receive prophylactic therapy for toxoplasmosis and Cryptococcus meningitis.[152] Appropriate preventive measures have reduced the rate of these infections by 50% between 1992 and 1997.[153]
由愛滋帶原母親產下的嬰兒建議於出生四至六週時服用[複方新諾明]]（英文：Trimethoprim/sulfamethoxazole）以預防伺機性感染，尤其是[[肺囊蟲肺炎]][150]。而此藥物在血液中CD+4輔助T細胞的數量每微升少於200個，或先前有[[肺囊蟲肺炎]]的病史時，也用來預防[[肺囊蟲肺炎]][151]。其它可能伺機性感染包括[[弓蟲症|弓形蟲感染]]和[[隱球菌屬|隱球菌]]腦膜炎[152]。由於適當的預防措施，愛滋病患伺機性感染發生率在1992年至1997年間下降了約50%[153]。
===Diet飲食調整===
Main article: Nutrition and HIV/AIDS
The World Health Organization (WHO) has issued recommendations regarding nutrient requirements in HIV/AIDS.[154] A generally healthy diet is promoted. Some evidence has shown a benefit from micronutrient supplements.[155] Evidence for supplementation with selenium is mixed with some tentative evidence of benefit.[156] There is some evidence that vitamin A supplementation in children reduces mortality and improves growth.[155] In Africa in nutritionally compromised pregnant and lactating women a multivitamin supplementation has improved outcomes for both mothers and children.[155] Dietary intake of micronutrients at Recommended Dietary Allowance (RDA) levels by HIV-infected adults is recommended by the WHO; higher intake of vitamin A, zinc, and iron can produce adverse effects in HIV positive adults, and is not recommended unless there is documented deficiency.[154][157][158][159]
[[世界衛生組織]]針對愛滋病患者的營養攝取有提出建議[154]。部分的證據指出，攝取[[微量元素]]的營養補充劑是有益的[155]。而補充[[硒]]對於患者是否有幫助，目前仍未有定論[156]。部分的研究指出，補充[[維生素A]]能幫助孩童的患者生長，並降低死亡率[155]。在非洲的研究指出，給予孕婦或哺乳中的婦女還有{{link-en|多種維生素|Multivitamin}}的補充劑，能同時帶給母親以及幼兒更多的益處[155]。
並且世界衛生組織提醒，愛滋病毒感染者攝取更高的的[[維生素A]]、[[鋅]]和[[鐵]]可能會產生不良的反應，除非確定身體內的含量不足，否則遵照每日{{link-en|飲食參考攝取量|Reference Daily Intake}}的建議即可[154][157][158][159]。
===Alternative medicine另類療法===
In the US, approximately 60% of people with HIV use various forms of complementary or alternative medicine,[160] even though the effectiveness of most of these therapies has not been established.[161] There is not enough evidence to support the use of herbal medicines.[162] There is insufficient evidence to recommend or support the use of medical cannabis to try to increase appetite or weight gain.[163]
在美國，約有60%的患者會使用[[替代醫學|另類療法]]，僅管大部份的另類療法都沒有證實其療效[160]。目前也沒有足夠的證據支持[[草藥醫學|草藥]]的療效[162]。而使用{{link-en|醫用大麻|Medical cannabis}}來增加食慾及體重的說法，也沒有足夠的證據給予支持[163]。
HIV/AIDS has become a chronic rather than an acutely fatal disease in many areas of the world.[164] Prognosis varies between people, and both the CD4 count and viral load are useful for predicted outcomes.[18] Without treatment, average survival time after infection with HIV is estimated to be 9 to 11 years, depending on the HIV subtype.[7] After the diagnosis of AIDS, if treatment is not available, survival ranges between 6 and 19 months.[165][166] HAART and appropriate prevention of opportunistic infections reduces the death rate by 80%, and raises the life expectancy for a newly diagnosed young adult to 20–50 years.[164][167][168] This is between two thirds[167] and nearly that of the general population.[19][169] If treatment is started late in the infection, prognosis is not as good:[19] for example, if treatment is begun following the diagnosis of AIDS, life expectancy is ~10–40 years.[19][164] Half of infants born with HIV die before two years of age without treatment.[150]
隨著醫學進步，愛滋病毒感染在許多國家已經從以往致命性的急性疾病成為可控制的慢性疾病[164]。預後因人而異，其中CD4數量以及病毒量是最常用的預測因子[18]。愛滋病毒感染後若未經治療，平均存活時間約9至11年，隨著不同病毒亞型有差異[7]。一旦發展成愛滋病，在未治療的情況下存活時間僅6至19個月[165][166]。死亡率在雞尾酒療法以及適當預防伺機性感染下可減少80%，在年輕感染族群的預期壽命更達20至50年[164][167][168]，接近一般大眾預期壽命的三分之二[167]甚或沒有差別[19][169]。然而若感染後期才接受治療，預後相對較差[19]：如在發病後接受治療，預期壽命在10至40年之間[19][164]。愛滋寶寶出生後若未接受適當治療，有一半在兩歲前死亡[150]。
The primary causes of death from HIV/AIDS are opportunistic infections and cancer, both of which are frequently the result of the progressive failure of the immune system.[153][170] Risk of cancer appears to increase once the CD4 count is below 500/μL.[19] The rate of clinical disease progression varies widely between individuals and has been shown to be affected by a number of factors such as a person’s susceptibility and immune function;[171] their access to health care, the presence of co-infections;[165][172] and the particular strain (or strains) of the virus involved.[173][174]
免疫系統逐漸瓦解會造成伺機性感染及愛滋相關腫瘤的發生，而此兩者是愛滋病患者的主要死亡原因[153][170]。腫瘤發生率在CD4數量少於每微升500個時增加[19]。病程進展的速率有極大的個體差異，相關因子包括患者對病毒的易感程度、免疫功能高低[171]；醫療資源可近性、共同感染的病原種類[165][172]；以及愛滋病毒
Tuberculosis co-infection is one of the leading causes of sickness and death in those with HIV/AIDS being present in a third of all HIV infected people and causing 25% of HIV related deaths.[175] HIV is also one of the most important risk factors for tuberculosis.[176] Hepatitis C is another very common co-infection where each disease increases the progression of the other.[177] The two most common cancers associated with HIV/AIDS are Kaposi’s sarcoma and AIDS-related non-Hodgkin’s lymphoma.[170]
對於愛滋病患者最危險的疾病之一是結核病[176]，約有三分之一的愛滋病毒感染者會同時被結核桿菌感染，而同時愛滋病患者的死因中，約有25%亦是結核病所引起[175]。C型肝炎也是另一種常見於愛滋病患者身上的傳染性疾病，研究中發現，愛滋患者若一同感染多種疾病，皆會同時加速彼此的病程進展[177]。而好發於愛滋病患者的腫瘤，最常見的是卡波西氏肉瘤和非霍奇金氏淋巴瘤[170]。
Even with anti-retroviral treatment, over the long term HIV-infected people may experience neurocognitive disorders,[178] osteoporosis,[179] neuropathy,[180] cancers,[181][182] nephropathy,[183] and cardiovascular disease.[144] Some conditions like lipodystrophy may be caused both by HIV and its treatment.[144]
即便使用了抗反轉錄病毒的治療，被愛滋病毒長期感染的患者，仍然可能會出現以下的疾病：因神經受損而產生的認知障礙[178]；骨質疏鬆[179]；神經性疾病[180]；癌症[181][182]；腎臟疾病[183]以及心血管疾病[144]。而某些疾病的起因可能同時由愛滋病毒和抗反轉錄病毒的藥物所引起的，如脂質營養不良症候群[144]。
HIV/AIDS is a global pandemic.[185] As of 2012, approximately 35.3 million people have HIV worldwide with the number of new infections that year being about 2.3 million.[186] This is down from 3.1 million new infections in 2001.[186] Of these approximately 16.8 million are women and 3.4 million are less than 15 years old.[130] It resulted in about 1.34 million deaths in 2013,[9] down from a peak of 2.2 million in 2005.[130][186]
愛滋病目前已是全球性的傳染病[185]。截至2012年為止，全球感染愛滋病的人數約有3530萬人，且當年新增的病例就有2萬3千人左右[186]。相較於2001年時，當年新增病例約3萬1千人，2012年新增病例已經趨緩[186]。
得到愛滋病的患者中，約有1680萬人是婦女，而約有340萬人是年齡15歲以下的患者[130]。而死亡的病例數據來說，2013年死亡的病例約134萬人，相較於歷年的統計數字來說，死亡病例最高在2005年，該年有220萬患者死亡[130][186]。
Sub-Saharan Africa is the region most affected. In 2010, an estimated 68% (22.9 million) of all HIV cases and 66% of all deaths (1.2 million) occurred in this region.[187] This means that about 5% of the adult population is infected[188] and it is believed to be the cause of 10% of all deaths in children.[189] Here in contrast to other regions women compose nearly 60% of cases.[187] South Africa has the largest population of people with HIV of any country in the world at 5.9 million.[187] Life expectancy has fallen in the worst-affected countries due to HIV/AIDS; for example, in 2006 it was estimated that it had dropped from 65 to 35 years in Botswana.[10]Mother-to-child transmission, as of 2013, in Botswana and South Africa has decreased to less than 5% with improvement in many other African nations due to improved access to antiretroviral therapy.[190]
撒哈拉以南的非洲地區是受到愛滋病衝擊最嚴重的地區，截至2010年為止，全球的愛滋病患者中，估計約有68%的患者分佈於此地區 (約2290萬人)，而全球因愛滋病死亡的病例中，約有66%分佈於此地區 (約120萬人)[187]。此統計數據代表在該地區，約有5%的成人感染愛滋病毒，且在該地區的孩童死亡原因中，約有10%的孩童死亡是因為愛滋病所引起的[189]。
女性在全球病患的比例中，穩定的維持在50%，但在撒哈拉沙漠以南的非洲地區，卻約有60%的患者是女性，遠高於全球病患比例 (加勒比海地區，女性患者約為53%，比全球病患的比例稍高)。
南非目前是單一國家內，愛滋病患者最多的國家，約有590名萬者[187]。在受到愛滋病毒嚴重肆虐的國家，甚至於該國國民的平均壽命會受到嚴重的影響，例如南非的鄰國－博茨瓦纳共和國(Republic of Botswana)，於2006年的估計，該國國人的平均壽命因為愛滋病的影響，從65歲降到35歲[10]。而由於醫藥和衛生政策的進步，在抗反轉錄病毒療法的治療下，許多非洲國家的母子垂直感染現象已經減少，例如南非和博茨瓦纳共和國，在2013年的統計，已經降低為5%[190]。
South & South East Asia is the second most affected; in 2010 this region contained an estimated 4 million cases or 12% of all people living with HIV resulting in approximately 250,000 deaths.[188] Approximately 2.4 million of these cases are in India.[187]
南亞及東南亞是受到影響第二嚴重的地區，2012年為止，該地區約有400萬名愛滋病患者，並且約有12%感染到愛滋病毒的患者死亡，導致了約有25萬人的死亡[188]。而其中約有240萬名病例是分佈在印度[187]。
In 2008 in the United States approximately 1.2 million people were living with HIV, resulting in about 17,500 deaths. The US Centers for Disease Control and Prevention estimated that in 2008 20% of infected Americans were unaware of their infection.[191] In the United Kingdom as of 2009 there where approximately 86,500 cases which resulted in 516 deaths.[192] In Canada as of 2008 there were about 65,000 cases causing 53 deaths.[193] Between the first recognition of AIDS in 1981 and 2009 it has led to nearly 30 million deaths.[194] Prevalence is lowest in Middle East and North Africa at 0.1% or less, East Asia at 0.1% and Western and Central Europe at 0.2%.[188] The worst affected European countries, in 2009 and 2012 estimates, are Russia, Ukraine, Latvia, Moldova, Portugal and Belarus, in order of prevalence.[195]
據統計，2008年時，在美國約有120萬人受到感染，並且造成約17500名死亡病例，並且據美國疾病控制與預防中心評估，約有20%的被感染者並不清楚自己已經遭到感染[191]。而在英國，2009年時統計約有86500名患者，並且有516名患者死亡[192]。而2008年的加拿大，約有6萬5千名病例，死亡人數是53人[193]。從1981年的首名病例被辨識以來，截至2009年為止，愛滋病已經奪走了30萬人的生命[194]。
而全球以地區來做分類而言，得病比例最低的地區為中東和北非，皆在0.1%以下；東亞地區為0.1%；西歐和中歐為0.2%[188]。而得病比最高的歐洲國家，根據2009年以及2012年的統計，最嚴重的是俄羅斯、烏克蘭、拉脫維亞、摩爾多瓦、葡萄牙以及白俄羅斯等國家[195]。
而以中華民國境內的統計數據而言，截至2015年3月為止，感染愛滋病毒的本國籍患者約有3萬人 (包含已經死亡的病例，約有5千人)。以年齡層分佈分析，比例最大為25-34歲，約佔43%；其次為35-49歲，約佔27%；再其次為15-24歲，約佔23%。而男女比例而言，絕大多數患者為男性，約有2萬7千人。而以可能受到傳染的途徑分析，比例最大的是透過不安全性行為 (同性)傳染，約佔48%；其次為透過注射毒品傳染，約佔23%；再其次是透過不安全性行為 (異性)傳染，約佔18%。而感染愛滋病毒患者的通報個數最高峰出現在2005年，該年有3378例；去年2014年有2236例[附註3]。
===Discovery===
AIDS was first clinically observed in 1981 in the United States.[27] The initial cases were a cluster of injecting drug users and homosexual men with no known cause of impaired immunity who showed symptoms of Pneumocystis carinii pneumonia (PCP), a rare opportunistic infection that was known to occur in people with very compromised immune systems.[196] Soon thereafter, an unexpected number of homosexual men developed a previously rare skin cancer called Kaposi’s sarcoma (KS).[197][198] Many more cases of PCP and KS emerged, alerting U.S. Centers for Disease Control and Prevention (CDC) and a CDC task force was formed to monitor the outbreak.[199]
愛滋病首次在臨床上被紀錄是在1981年的美國[27]。最初的病例的分佈是集中在吸毒者以及男同性戀族群中，是一種會造成免疫功能低落，且會罹患肺囊蟲肺炎，並且同時可能會得到極為罕見的伺機性感染的不明疾病[196]。而之後並發現到，少部分患者會罹患卡波西氏肉瘤，此腫瘤在醫學進步的國家中相當罕見[197][198]。由於此不明疾病所引發的肺囊蟲肺炎和卡波西氏肉瘤越見頻繁，使得美國的疾病控制與預防中心開始著手研究此一不明的傳染病[199]。
In the early days, the CDC did not have an official name for the disease, often referring to it by way of the diseases that were associated with it, for example, lymphadenopathy, the disease after which the discoverers of HIV originally named the virus.[200][201] They also used Kaposi’s sarcoma and opportunistic infections, the name by which a task force had been set up in 1981.[202] At one point, the CDC coined the phrase "the 4H disease", since the syndrome seemed to affect homosexuals, heroin users, hemophiliacs, and Haitians.[203][204] In the general press, the term "GRID", which stood for gay-related immune deficiency, had been coined.[205] However, after determining that AIDS was not isolated to the gay community,[202] it was realized that the term GRID was misleading and the term AIDS was introduced at a meeting in July 1982.[206] By September 1982 the CDC started referring to the disease as AIDS.[207]
早期美國疾病控制與預防中心並未給予此疾病正式名稱，而是暫時以此疾病所引起的併發症為名，如：全身性淋巴結腫大症候群。而在未有正式名稱前，1981年也曾以卡波西氏肉瘤與伺機性感染為名[202]。其後發現了此疾病的病原體，愛滋病毒，便以此病毒名稱為疾病名[200][201]。
由於此疾病似乎同時影響同性戀族群、海洛因使用者、血友病患者以及海地人，所以早期美國疾病控制與預防中心也曾以「4H疾病」 (因上述四個族群在英語中皆是以H開頭的單字)為名[203][204]。而在媒體業，由於此疾病較常見於男同性戀族群，因此也有「GRID」的簡稱 (gay-related immune deficiency)[205]。然而，醫界發現到此疾病不會只影響單一特定族群，因此在1982年的7月，開始呼籲使用正式病名，並且避免使用其它稱呼[206]。而早期美國疾病控制與預防中心在同年的11月，正式稱呼此疾病為愛滋病[207]。
In 1983, two separate research groups led by Robert Gallo and Luc Montagnier independently declared that a novel retrovirus may have been infecting people with AIDS, and published their findings in the same issue of the journal Science.[208][209] Gallo claimed that a virus his group had isolated from a person with AIDS was strikingly similar in shape to other human T-lymphotropic viruses (HTLVs) his group had been the first to isolate. Gallo’s group called their newly isolated virus HTLV-III. At the same time, Montagnier’s group isolated a virus from a person presenting with swelling of the lymph nodes of the neck and physical weakness, two characteristic symptoms of AIDS. Contradicting the report from Gallo’s group, Montagnier and his colleagues showed that core proteins of this virus were immunologically different from those of HTLV-I. Montagnier’s group named their isolated virus lymphadenopathy-associated virus (LAV).[199] As these two viruses turned out to be the same, in 1986, LAV and HTLV-III were renamed HIV.[210]
1983年，分別由Robert Gallo和Luc Montagnier所領導的研究團隊，各自獨立地從罹患愛滋病的患者身上分離出新的反轉錄病毒，並且發表於同期的「科學(Science)」雜誌[208][209]。
Gallo的團隊是由一名患者身上分離出一株新的病毒，此病毒和人類T淋巴球病毒 (human T-lymphotropic viruses/HTLVs)極為類似，該團隊聲稱這是世界上首次分離出愛滋病毒，並且稱此病毒為HTLV-III。在同一時間，Montagnier的團隊從一名虛弱的愛滋病患者身上的腫大的頸部淋巴中分離出新的病毒，但和Gallo團隊的結論不同，Montagnier的團隊利用免疫分析的技術，判斷此新病毒病非HTLV的一員，因此Montagnier的團隊稱此病毒為淋巴結相關病毒(lymphadenopathy-associated virus/LAV)[199]。
而在之後的研究裡終於發現，Gallo和Montagnier的團隊所分離的新病毒其實是同一種病毒，因此重新更名為愛滋病毒 (human immunodeficiency virus/HIV)[210]。
===Origins===
Both HIV-1 and HIV-2 are believed to have originated in non-human primates in West-central Africa and were transferred to humans in the early 20th century.[11] HIV-1 appears to have originated in southern Cameroon through the evolution of SIV(cpz), a simian immunodeficiency virus (SIV) that infects wild chimpanzees (HIV-1 descends from the SIVcpz endemic in the chimpanzee subspecies Pan troglodytes troglodytes).[211][212] The closest relative of HIV-2 is SIV(smm), a virus of the sooty mangabey (Cercocebus atys atys), an Old World monkey living in coastal West Africa (from southern Senegal to western Côte d’Ivoire).[77] New World monkeys such as the owl monkey are resistant to HIV-1 infection, possibly because of a genomic fusion of two viral resistance genes.[213] HIV-1 is thought to have jumped the species barrier on at least three separate occasions, giving rise to the three groups of the virus, M, N, and O.[214]
目前愛滋病毒分為1型和2型兩個亞種 (HIV-1、HIV-2)，通常被認為是在20世紀初的西部或中部非洲地區，由非人類的靈長類動物將病毒傳播給人類[11]。
HIV-1目前認為是由黑猩猩 (central chimpanzee (Pan troglodytes troglodytes))的猴免疫缺陷病毒(simian immunodeficiency virus /SIV) (SIV(cpz)，cpz意指黑猩猩)演化而來，演化的地點可能為於現今喀麥隆的南部地區(HIV-1的祖先，被認為是黑猩猩的地方性疾病的病原體，猴免疫缺陷病毒演化而來)[211][212]。而目前的研究中，和HIV-2最接近的病毒是烏黑白眉猴(sooty mangabey monkeys (Cercocebus atys atys))的猴免疫缺陷病毒 (SIV(smm)，smm意指烏黑白眉猴)，烏黑白眉猴屬舊世界猴，生活於西非沿海地區(大約是從塞內加爾南部到象牙海岸共和國的西部)[77]。
而愛滋病毒已經能夠跨越物品屏障，具備感染多個物種動物的能力。而HIV-1依外套模的不同，至少尚可分為三個族群：M、N和O，其中M型分佈最廣，其中又可分為多種型 (A, B, C, D, F, G, H, J, K和circulating recombinant forms，CRFs)，B型常見於北美和歐洲；A及D型常見於非洲；C型則多半分佈在非洲和亞洲[附註4]。
There is evidence that humans who participate in bushmeat activities, either as hunters or as bushmeat vendors, commonly acquire SIV.[215] However, SIV is a weak virus which is typically suppressed by the human immune system within weeks of infection. It is thought that several transmissions of the virus from individual to individual in quick succession are necessary to allow it enough time to mutate into HIV.[216]Furthermore, due to its relatively low person-to-person transmission rate, SIV can only spread throughout the population in the presence of one or more high-risk transmission channels, which are thought to have been absent in Africa before the 20th century.
目前的證據顯示，當獵人捕獲了感染猴免疫缺陷病毒的動物時，不論是獵人或是轉手買賣受到汙染的獵物的商人，都可能會受到猴免疫缺陷病毒的感染[215]。然而，對人類的免疫系統來說，猴免疫缺陷病毒是一種危害較輕的病毒，數週內就能夠被人類的免疫系統清除。然而，被感染的人快速的將病毒傳染給下一名宿主，如此反覆之下，猴免疫缺陷病毒可能就會突變演化成愛滋病毒[216]。然而，由於猴免疫缺陷病毒透過人傳人的途徑傳播的效率較低，因此這種傳播的方式只能在高風險的環境下才會出現，而20世紀之前，非洲人口尚不普遍，因此尚未形成有利於猴免疫缺陷病毒透過人傳人途徑演化的環境，所以可以合理的猜測，猴免疫缺陷病毒突變演化為愛滋病毒，應該是在20世紀時，非洲人口增長之後才發生的事。
Specific proposed high-risk transmission channels, allowing the virus to adapt to humans and spread throughout the society, depend on the proposed timing of the animal-to-human crossing. Genetic studies of the virus suggest that the most recent common ancestor of the HIV-1 M group dates back to circa 1910.[217] Proponents of this dating link the HIV epidemic with the emergence of colonialism and growth of large colonial African cities, leading to social changes, including a higher degree of sexual promiscuity, the spread of prostitution, and the accompanying high frequency of genital ulcer diseases (such as syphilis) in nascent colonial cities.[218] While transmission rates of HIV during vaginal intercourse are low under regular circumstances, they are increased many fold if one of the partners suffers from a sexually transmitted infection causing genital ulcers. Early 1900s colonial cities were notable due to their high prevalence of prostitution and genital ulcers, to the degree that, as of 1928, as many as 45% of female residents of eastern Kinshasa were thought to have been prostitutes, and, as of 1933, around 15% of all residents of the same city had syphilis.[218]
而高風險的傳播環境，指的是病毒逐漸適應人類，並且能夠在人類族群中順利地傳播，這需要仰賴人類持續地與動物的接觸時間，兩者交流的時間越久，跨物種的傳染機率越高。目前基因學的研究顯示，HIV-1 M的祖先可以追朔到西元1910年[217]。這項證據顯示，愛滋病的擴散和殖民主義息息相關，由於殖民的過程中，使非洲的大城市興起，人口增長與集中，並且改變了社會的風氣，在這些新興的城市中，性行為更加的開放，性交易開始普遍，而會導致生殖器潰瘍的疾病泛濫等等的因素，加速了愛滋病毒的演化[218]。而高風險的傳播環境，指的是病毒逐漸適應人類，並且能夠在人類族群中順利地傳播，這需要仰賴人類持續地與動物的接觸，兩者交流的時間越久，跨物種的傳染機率越高。
目前基因學的研究顯示，HIV-1 M的祖先可以追朔到西元1910年[217]。這項證據顯示，愛滋病的擴散和殖民主義息息相關，由於殖民的過程中，使非洲的大城市興起，人口增長與集中，並且改變了社會的風氣，在這些新興的城市中，性行為更加的開放，性交易開始普遍，而會導致生殖器潰瘍的疾病(如：梅毒)泛濫等等的因素，加速了愛滋病毒的演化[218]。
雖然愛滋病毒透過陰道性交傳播是效率相對較低的途徑，但如果性交的任何一方，其生殖器因為其他性病產生潰瘍，則愛滋病毒的傳染能力就會大幅度地提高。由於上個世紀初，在人口集中的城市裡，性交易的行為普遍，同時會導致生殖器潰瘍的性病亦泛濫，雙重的因素更加快了愛滋病毒的演化。據統計，1928年時，金夏沙 (剛果共和國首都)西部地區的婦女，可能約有45%曾從事性交易的行為；而1933年時，該城市人口約有15%的居民患有梅毒[218]。
An alternative view holds that unsafe medical practices in Africa after World War II, such as unsterile reuse of single use syringes during mass vaccination, antibiotic and anti-malaria treatment campaigns, were the initial vector that allowed the virus to adapt to humans and spread.[216][219][220]
而另一個觀點認為，在第二次世界大戰之後，有許多不安全的醫療行為在非洲被施行，如：大規模的接種疫苗、注射抗生素以及注射抗瘧疾的藥物，由於這些醫療行為並未消毒針頭，並且會重複使用，這些不安全的醫療行為，是使得愛滋病毒開始有了適應人類的機會[216][219][220]。
The earliest well documented case of HIV in a human dates back to 1959 in the Congo.[221] The virus may have been present in the United States as early as 1966,[222] but the vast majority of infections occurring outside sub-Saharan Africa (including the U.S.) can be traced back to a single unknown individual who became infected with HIV in Haiti and then brought the infection to the United States some time around 1969.[223] The epidemic then rapidly spread among high-risk groups (initially, sexually promiscuous men who have sex with men). By 1978, the prevalence of HIV-1 among homosexual male residents of New York and San Francisco was estimated at 5%, suggesting that several thousand individuals in the country had been infected.[223]
而最早有證據顯示人類感染愛滋病毒，可以追溯到1959年的剛果[221]。在美國，最早有證據顯示人類受到感染，可以追溯到1966年[222]，據推測是居住在海地的患者，傳播到美國境內[223]。不過此時愛滋病毒的患者，大多仍分佈在美國或撒哈拉沙漠以南的非洲地區。而透過許多高風險的族群(男性之間的性濫交行為)，愛滋病開始在人類世界中快速的傳播出去。據評估，1978年時，在紐約和舊金山的男同性戀族群中，約有5%患有愛滋病，代表在美國境內，此時至少已經有數千名患者了[223]。
===疾病汙名化Stigma===
AIDS stigma exists around the world in a variety of ways, including ostracism, rejection, discrimination and avoidance of HIV infected people; compulsory HIV testing without prior consent or protection of confidentiality; violence against HIV infected individuals or people who are perceived to be infected with HIV; and the quarantine of HIV infected individuals.[224] Stigma-related violence or the fear of violence prevents many people from seeking HIV testing, returning for their results, or securing treatment, possibly turning what could be a manageable chronic illness into a death sentence and perpetuating the spread of HIV.[225]
世界各地皆有出現對於愛滋病患者產生歧視、排斥或不理性的恐懼等行為，其中包含刻意區分且隔離愛滋病患者；強制性的進行愛滋病毒的篩檢；以暴力對待愛滋病患者或疑似感染愛滋病的人[224]。因為對愛滋病的誤解和歧視所引起的暴力和恐懼，可能會使得人們畏懼進行愛滋病的檢測，或拒絕接受檢測後的結果以及治療。這種結果會錯失將愛滋病抑制成慢性疾病的機會，可能會導致患者死亡，並且會使得愛滋病更容易被傳播出去[225]。
而中華民國政府方面也曾出現有所爭議的歧視事件，1997年美國知名籃球選手魔術強森 （Earvin Johnson, Jr.）受邀來台，但當時衛生署依愛滋病防治條例拒絕魔術強森來台。而在1997年底修改愛滋病防治條例內文，外籍愛滋感染者「應」令其離境，改為「得」令其離境[附註5]。而在2002年，澳洲社會學者（Susan Paxton）成為首位被確診 （且入境時誠實通報）之訪台的外籍人士[附註6]。
AIDS stigma has been further divided into the following three categories:
Often, AIDS stigma is expressed in conjunction with one or more other stigmas, particularly those associated with homosexuality, bisexuality, promiscuity, prostitution, and intravenous drug use.[228]
目前對於愛滋病的汙名化可約略區分成三類
通常對愛滋病的汙名化會連結到許多的議題或團體，較常見的有同性戀；雙性戀；性交易；對性行為較開放的族群；靜脈注射毒品的族群等[228]。
In many developed countries, there is an association between AIDS and homosexuality or bisexuality, and this association is correlated with higher levels of sexual prejudice, such as anti-homosexual/bisexual attitudes.[229] There is also a perceived association between AIDS and all male-male sexual behavior, including sex between uninfected men.[226] However, the dominant mode of spread worldwide for HIV remains heterosexual transmission.[230]
In 2003, as part of an overall reform of marriage and population legislation, it became legal for people with AIDS to marry in China.[231]
即使在許多開發程度較高國家，社會上仍會將愛滋病與特定族群作聯想或不當的連結，例如同性戀或雙性戀族群，進而引發對於性向選取的歧視和恐懼 (例如：[[同性戀恐懼症|恐同症/同性戀恐懼症]])[附註6]，例如會有反同性戀/雙性戀的主張[229]。僅管愛滋病透過男性與男性之間的性行為傳播，仍有相當的比例，但是目前全球的傳播途徑來說，主要仍是透過由異性之間的性行為來傳播愛滋病[230]。僅管對愛滋病的歧視短期內無法消除，但仍有令人稱許的進展，例如在2003年，中國改革了婚姻以及人口方面的法令，承認愛滋病患者婚姻的合法性[231]。
===經濟層面Economic impact===
HIV/AIDS affects the economics of both individuals and countries.[189] The gross domestic product of the most affected countries has decreased due to the lack of human capital.[189][232] Without proper nutrition, health care and medicine, large numbers of people die from AIDS-related complications. They will not only be unable to work, but will also require significant medical care. It is estimated that as of 2007 there were 12 million AIDS orphans.[189] Many are cared for by elderly grandparents.[233]
愛滋病嚴重肆虐時甚至會動搖國家的經濟實力，因為愛滋病使人民的平均壽命減少 (例如：[[賴索托]]、[[南非]]、[[波札那]])，進而影響到國家的生產力以及國內生產總額 (gross domestic product/GDP)[189][232]。如果沒有適當的醫療、醫藥和公衛機制控制愛滋病的疫情，將會有大量的人口死於愛滋病的併發症。疫情嚴重泛濫之下，患者不僅無法工作，更需要龐大的醫療資源進行照護，並且在患者去世之後，更會留下無人照顧的幼兒，根據統計，2007年因此約有12萬名孩童成為孤兒[189]，迫使祖父母必須要取代父母照顧他們[233]。
By affecting mainly young adults, AIDS reduces the taxable population, in turn reducing the resources available for public expenditures such as education and health services not related to AIDS resulting in increasing pressure for the state’s finances and slower growth of the economy. This causes a slower growth of the tax base, an effect that is reinforced if there are growing expenditures on treating the sick, training (to replace sick workers), sick pay and caring for AIDS orphans. This is especially true if the sharp increase in adult mortality shifts the responsibility and blame from the family to the government in caring for these orphans.[233]
At the household level, AIDS causes both loss of income and increased spending on healthcare. A study in Côte d’Ivoire showed that households having a person with HIV/AIDS spent twice as much on medical expenses as other households. This additional expenditure also leaves less income to spend on education and other personal or family investment.[234]
由於青壯年齡層容易受到愛滋病的影響，愛滋病肆虐嚴重的國家，不僅納稅的人口會因病減少，而青壯人口的劇減，更會壓縮其它方面的人力供應(如：教育、醫療等)，多方因素更加速了該國的經濟力量下降。即便是提供治療，患者因病而請假，導致可勞動的工時減少，或是重新培訓勞工以補充不足的勞動力，上述的因素亦是愛滋病拖垮一國經濟的原因。特別是如果該國沒有良好的措施或藥物來應對愛滋病，使得成人的死亡人口遽增，導致需要照護的愛滋孤兒數量提高，更使得政府 (或家族中其他可勞動的人口)的負擔更重[233]。
以家庭的觀點來看，家庭中成員感染愛滋病，不僅可能損失經濟來源，更加重了醫療的負擔。在象牙海岸的一項研究表明，若是家庭中有一名成員感染愛滋病，該家庭的醫療支出是一般家庭的兩倍之多，因此勢必壓縮了該家庭在教育或是其他方面的投資[234]。
===宗教與愛滋Religion and AIDS===
The topic of religion and AIDS has become highly controversial in the past twenty years, primarily because some religious authorities have publicly declared their opposition to the use of condoms.[235][236] The religious approach to prevent the spread of AIDS according to a report by American health expert Matthew Hanley titled The Catholic Church and the Global AIDS Crisis argues that cultural changes are needed including a re-emphasis on fidelity within marriage and sexual abstinence outside of it.[236]
在過去數十年間，宗教對於愛滋病的立場以及影響一直有所爭論，其中一項因素是部分宗教公開反對使用保險套[235][236]。而部分宗教的主張似乎對於預防愛滋病的傳播沒有效果，例如美國健康學者Matthew Hanley曾發表一篇研究，指出部分天主教會認為防治愛滋病的關鍵在於文化的重新塑造，包含強調婚姻的忠貞以及禁慾等[236]。而在近年來，中華民國內的部分宗教人士因觀念不同或是誤解，刻意汙名化愛滋病或是特定族群[附註7][附註8]。
Some religious organisations have claimed that prayer can cure HIV/AIDS. In 2011, the BBC reported that some churches in London were claiming that prayer would cure AIDS, and the Hackney-based Centre for the Study of Sexual Health and HIV reported that several people stopped taking their medication, sometimes on the direct advice of their pastor, leading to a number of deaths.[237] The Synagogue Church Of All Nations advertise an "anointing water" to promote God’s healing, although the group deny advising people to stop taking medication.[237]
部分宗教組織聲稱透過祈禱能治癒愛滋病。而在2011年，英國廣播公司(British Broadcasting Corporation/BBC)報導，部分在倫敦教堂的牧師聲稱祈禱能夠治癒愛滋病，而根據Hackney-based Centre的研究報告，有數人因此停止服藥，導致部分患者死亡[237]。而部分的猶太教會，聲稱服用聖水 (anointing water)能使上帝治癒愛滋病，雖然並未建議停止服藥，但其主張仍飽受爭議[237]。
===著名愛滋病患者Media portrayal===
One of the first high-profile cases of AIDS was the American Rock Hudson, a gay actor who had been married and divorced earlier in life, who died on 2 October 1985 having announced that he was suffering from the virus on 25 July that year. He had been diagnosed during 1984.[238] A notable British casualty of AIDS that year was Nicholas Eden, a gay politician and son of the late prime minister Anthony Eden.[239] On November 24, 1991, the virus claimed the life of British rock star Freddie Mercury, lead singer of the band Queen, who died from an AIDS-related illness having only revealed the diagnosis on the previous day.[240] However, he had been diagnosed as HIV positive in 1987.[241] One of the first high-profile heterosexual cases of the virus was Arthur Ashe, the American tennis player. He was diagnosed as HIV positive on August 31, 1988, having contracted the virus from blood transfusions during heart surgery earlier in the 1980s. Further tests within 24 hours of the initial diagnosis revealed that Ashe had AIDS, but he did not tell the public about his diagnosis until April 1992.[242] He died, aged 49, as a result on February 6, 1993.[243]
在美國，早期最受矚目的感染病例是Rock Hudson，是一名同性戀的演員。早年曾結婚但隨即離婚，在1984年被診斷出罹患愛滋病[238]，在1985年7月25日確診被愛滋病毒感染，同年的10月2日去世。在英國，Nicholas Eden這名患者的確診受到關注，因為他是同性戀的政治人物，同時也是前首相Anthony Eden的兒子[239]。而英國搖滾明星Freddie Mercury (Queen樂團的主唱)在1987年確診為愛滋病陽性，而在1991年11月24日去世[240]。而異性戀病例中，美國網球選手Arthur Ashe是首次被大幅度報導的。疑似是在80年代進行心臟手術，在輸血過程中受到感染，他在1988年8月31日確診為愛滋病陽性，然而直到1992年4月才公開病情[242]，而在1993年2月6日去世[243]。
Therese Frare’s photograph of gay activist David Kirby, as he lay dying from AIDS while surrounded by family, was taken in April 1990. LIFE magazine said the photo became the one image "most powerfully identified with the HIV/AIDS epidemic." The photo was displayed in LIFE magazine, was the winner of the World Press Photo, and acquired worldwide notoriety after being used in a United Colors of Benetton advertising campaign in 1992.[244] In 1996, Johnson Aziga, a Ugandan-born Canadian was diagnosed with HIV, but subsequently had unprotected sex with 11 women without disclosing his diagnosis. By 2003 seven had contracted HIV, and two died from complications related to AIDS.[245][246] Aziga was convicted of first-degree murder and is liable to a life sentence.[247]
Therese Frare先生在1990年4月攝影了一張照片，是一名愛滋病的行動主義者－David Kirby先生因為愛滋病而去世的最後一天，David Kirby躺在床上而四周環繞著他的家人。此一照片對社會造成了強大的衝擊，「生活 (Life)」雜誌聲稱這是對於愛滋病肆虐的最有利證明。該照片被刊登在「生活」雜誌上，並且獲得世界攝影的冠軍。然而，David Kirby先生的家人允許Benetton服裝公司使用該照片於商業用途時卻引起了爭議，部分天主教教會認為該照片暗示聖母瑪莉亞懷抱著受難的耶穌[附註8]。
===蓄意傳播愛滋病毒Criminal transmission===
Criminal transmission of HIV is the intentional or reckless infection of a person with the human immunodeficiency virus (HIV). Some countries or jurisdictions, including some areas of the United States, have laws that criminalize HIV transmission or exposure.[248]Others, may charge the accused under existing laws.
蓄意傳播愛滋病毒，在許多國家都被視為犯罪的行為，例如在美國[248]；中華民國[附註9]。
在1996年，Johnson Aziga先生，一名在烏干達出生的加拿大人被確診感染愛滋病毒，然而之後卻在未告知病情的情況之下，和11名婦女進行不安全的性行為。截至2003年為止，有7人因此感染了愛滋病毒，並且有2人因為愛滋病的併發症而死亡[245][246]。Johnson Aziga被判一級謀殺罪，最高可求處死刑[247]。
而在中華民國，也曾出現已知自己為愛滋病毒的帶原者，卻仍然進行不安全性行為的患者，因此被法院依<人類免疫缺乏病毒傳染防治及感染者權益保障條例>判處13年有期徒刑[附註10]。亦有特意隱瞞自己病情而與他人進行不安全性行為的案例，亦遭到判刑[附註11]。
===誤解Misconceptions===
There are many misconceptions about HIV and AIDS. Three of the most common are that AIDS can spread through casual contact, that sexual intercourse with a virgin will cure AIDS,[249][250][251] and that HIV can infect only gay men and drug users. In 2014, some among the British public wrongly thought you could get HIV from kissing (16%), sharing a glass (5%), spitting (16%), a public toilet seat (4%), and coughing or sneezing (5%).[252] Other misconceptions are that any act of anal intercourse between two uninfected gay men can lead to HIV infection, and that open discussion of HIV and homosexuality in schools will lead to increased rates of AIDS.[253][254]
僅管愛滋病發現已數十年，在科學發達的現今仍有許多的誤解。常見的誤解包括有：愛滋病會透過日常生活行為而傳染；與處女性交能治癒愛滋病；愛滋病只會感染男同性戀者或吸毒犯[249][250][251]。2014年在英國的調查，仍有一定比例的國民認為愛滋病會透過以下的日常生活行為傳染：接吻(16%受訪者認為會透過此行為傳染)；共用同一個玻璃器皿(5%受訪者認為會透過此行為傳染)；使用公用廁所的坐墊(4%受訪者認為會透過此行為傳染)；吐痰(16%受訪者認為會透過此行為傳染)；咳嗽或打噴嚏(5%受訪者認為會透過此行為傳染)[252]。
其他常見的誤解尚有：未受感染的男同性戀之間互動，會因此得到愛滋病；以及在學校公開討論愛滋病或是同性戀的議題，會使得學校內的愛滋病因此氾濫[253][254]。而在中華民國，以反對同性戀以及多元成家而著名的「台灣宗教團體愛護家庭大聯盟 (簡稱：護家盟)」，在其主張裡，將同性戀族群和愛滋病作連結，並進而主張反對推動同性婚姻以及多元成家的相關法令[附註12]，然而此一主張在社會上受到抨擊以及反彈[附註13]。
A small group of individuals continue to dispute the connection between HIV and AIDS,[255] the existence of HIV itself, or the validity of HIV testing and treatment methods.[256][257] These claims, known as AIDS denialism, have been examined and rejected by the scientific community.[258] However, they have had a significant political impact, particularly in South Africa, where the government’s official embrace of AIDS denialism (1999–2005) was responsible for its ineffective response to that country’s AIDS epidemic, and has been blamed for hundreds of thousands of avoidable deaths and HIV infections.[259][260][261]
Several discredited conspiracy theories have held that HIV was created by scientists, either inadvertently or deliberately. Operation INFEKTION was a worldwide Soviet active measures operation to spread the claim that the United States had created HIV/AIDS. Surveys show that a significant number of people believed – and continue to believe – in such claims.[262]
有少部分人士質疑愛滋病毒和愛滋病之間的關連[255]，或是質疑愛滋病毒的檢測方式以及治療的方法[256][257]。這些質疑的聲浪，通常被稱為AIDS denialism，其論點都無法在科學的檢驗下獲得支持[258]。但這些論點卻受到部分的政治人物的支持，進而影響到該國的愛滋病防疫政策，最顯著的例子是南非，塔博·姆貝基 (Thabo Mbeki)總統 (任期：1999年－2008年)以及任內的曼托·沙巴拉拉 (Manto Tshabalala-Msimang)衛生部長 (任期：1999年－2008年)拒絕承認南非的國民因愛滋病肆虐而銳減，堅持人口衰退的原因是來自於營養不良和貧困，直至2007年，才因國際的壓力和抨擊下展開防疫的政策[259][260][261]。
也有陰謀論認為愛滋病毒是由科學家無意或蓄意製造出來的，可能是由蘇聯或美國的秘密組織有企圖地散播到世界。僅管這些陰謀論並無根據，但仍有人相信此一論點[262]。
HIV/AIDS research includes all medical research which attempts to prevent, treat, or cure HIV/AIDS along with fundamental research about the nature of HIV as an infectious agent and AIDS as the disease caused by HIV.
Many governments and research institutions participate in HIV/AIDS research. This research includes behavioral health interventions such as sex education, and drug development, such as research into microbicides for sexually transmitted diseases, HIV vaccines, and antiretroviral drugs. Other medical research areas include the topics of pre-exposure prophylaxis, post-exposure prophylaxis, and circumcision and HIV.
愛滋病的醫療研究中，為數眾多的研究團隊試圖以預防、治療或治癒為目標，進行了許多的基礎醫學研究。許多的國家也投入了龐大的心力進行研究開發。而在公共衛生上，例如性教育，也開始有了進展。而目前的藥物研究上，正朝著殺菌劑、愛滋病疫苗和抗反轉錄病毒藥物的方向前進。而其它的方向，比方說暴露前預防、暴露後預防以及割禮和愛滋病的關係等，也都有團隊進行研究。