艾滋病即获得性免疫缺陷综合征(简称AIDS)，是由人类免疫缺陷病毒(简称HIV，俗称艾滋病病毒)引起的传染病。艾滋病最早于1981年在男同性恋者中被发现，之后以惊人的速度传播和蔓延，目前已造成全球2500多万人死亡，现存HIV感染者3300多万。今年12月1日是第23个世界艾滋病日，主题是“权益、责任、落实”。
高危因素有哪些？
引起AIDS的病原——HIV进入人体后，主要侵犯人体的免疫系统，攻击和杀伤人体免疫系统中起重要作用的CD4+T淋巴细胞，从而破坏人体的免疫功能，使感染者免疫功能下降而后发生各种机会性感染和肿瘤。
2008年南非艾滋病大会提出：预防、治疗和关爱是人类抵御艾滋病的三大法宝。随着时代进步，我们要重新认识艾滋病，不要以为感染了HIV就得了不治之症。艾滋病可防可治，一旦感染HIV，进行积极的随访和治疗，可大大延长寿命，提高生活质量。
HIV传播途径主要有三个：
1、性接触传播
艾滋病感染者的精液或阴道分泌物中有大量病毒，在性活动(包括阴道性交、肛交和口交)时，可以通过生殖器或直肠黏膜传播。生殖器患有性病(如梅毒、淋病、尖锐湿疣)或溃疡时，会增加感染HIV的危险。直肠的肠壁较阴道壁更容易破损，所以肛门性交的危险性比阴道性交的危险性更大。故男同性恋人群为HIV感染的高危人群。
2、血液传播
输注含有HIV病毒的血制品可以感染HIV，包括血浆、红细胞悬液、血小板和凝血因子等。所以需要长期接受血制品的患者具有感染HIV的高风险，例如血友病患者。另外，共用针具也是引起HIV经血液传播的一种途径，使用不洁针具可以把艾滋病毒从一个人传到另一个人。例如：静脉吸毒者共用针具。此外，使用被HIV污染的血液而又未经严格消毒的注射器、针灸针、拔牙工具、美容针、剃须刀等，都十分危险。
3、母婴传播：
感染HIV的孕妇在妊娠期间、分娩过程中都有可能把HIV传给胎儿，分娩后通过母乳喂养也有将HIV传给孩子的风险，故HIV感染者要有计划在全程干预下生育，如已生育要避免母乳喂养。
男性同性恋者、静脉吸毒者以及多性伴侣者为HIV感染的高危人群。目前随着艾滋病流行疫情日趋严峻，艾滋病正逐渐从高危人群向普通人群扩散，当前艾滋病疫情形势极其严峻。然而，在低中收入国家尚有80%的HIV感染者不知自己的感染状态，已经发现的艾滋病患者只为“冰山一角”。
艾滋病已步入可治阶段
抗病毒治疗是艾滋病最根本的治疗。高效联合抗反转录病毒治疗（简称HAART），即俗称的“鸡尾酒疗法”，是目前已被证实的针对HIV感染最有效的治疗方法。它由美籍华人何大一教授于1995年提出，该疗法要求至少三种不同种类的药物联合使用，因其与鸡尾酒的配制形式相似而得名。自从HAART应用于临床以来，艾滋病患者的发病率和死亡率得到了大大降低。
艾滋病的治疗经历了“不治”、“难治”和“可治”阶段。1981～1987年，人们致力于艾滋病病因及致病机制的研究，临床尚无用于治疗艾滋病的药物，故艾滋病处于“不治”时期。1987～1996年，相继有抗反转录病毒药物上市，但这些药物的作用机制相似，但用或联合使用的抗病毒效果不佳，极易诱发病毒的耐药性产生而导致治疗失败，故此时期为艾滋病的“难治”阶段。从1996年至今，艾滋病防治进入“可治阶段”。这是由于具有不同作用机制的药物问世的结果。目前，获FDA批准的用于治疗艾滋病的药物共有6大类32种，包括核苷类反转录酶抑制剂、非核苷类反转录酶抑制剂、蛋白酶抑制剂、整合酶抑制剂、CCR5抑制剂（一种辅助受体抑制剂）、融合抑制剂。它们作用于HIV复制周期的多个环节，不同方式的优化组合使用可有效抑制病毒的复制，提升患者的CD4细胞计数，重建免疫功能，使患者寿命得以显著延长，让艾滋病患者看到了长期生存的曙光。
患者的免疫功能状态及临床症状是决定是否开始HAART治疗的依据。抗病毒治疗时机的确定是个非常复杂的问题，要综合考虑多种因素，尽可能使患者获得最大的临床收益。至于HAART开始的最佳时机，随着时间推移观点在不断改变。过去主张当CD4计数低于200个/微升时开始治疗，这样可以减少治疗费用和药物毒副反应，降低耐药发生率，保留更多的耐药后二线药物选择的余地。然而，近期多项研究结果支持尽早开始抗病毒治疗，以使患者有更多的机会获得免疫功能重建，减少机会感染的发生和AIDS相关病死率。
所以，目前指南推荐艾滋病患者开始抗病毒治疗的时机为：
①有AIDS相关症状；
②无症状，但CD4<350个/微升；
③CD4350个/微升，但存在以下情况时也可考虑治疗：高病毒载量（>10000）、CD4计数下降较快（每年降低>100个/微升）、心血管疾病高风险、合并HBV/HCV感染、HIV相关肾脏疾病。因早期开始抗病毒治疗可给患者带来较大的临床收益，故日后提早开始抗病毒治疗也许会成为一种趋势。
【温馨提示】
★坚持规律服药是治疗成败的关键。
患者一旦开始抗病毒治疗，就要按时按量规律服药，即保证有良好的服药依从性。因为，现已证实患者的服药依从性是关系抗病毒治疗成败的关键问题。另外，不规律服药还可导致病毒耐药性的产生。为了取得良好的抗病毒治疗效果，一般要求服药依从性达到95%以上。简化用药方案是提高患者依从性的重要措施之一，包括减少服药种类和服药次数、以及延长服药间隔等。
★定期随访监测是及时调整方案的依据。
感染早期者原则上可以每个季度随访一次；对于潜伏中、晚期尤其是那些发现过一次异常情况的患者原则上每个月随访一次。艾滋病患者抗病毒治疗过程中要定期随访，通过实验室检查（CD4细胞计数，病毒载量，血生化检查等）及临床指标监测以观察抗病毒治疗效果及药物不良反应。治疗效果不佳时还要进行耐药性检测，为更换二线药物提供依据。
积极治疗可延长寿命
虽然目前的HAART治疗不能从体内完全清除艾滋病病毒，但它可以尽可能长期地抑制病毒复制，将病毒载量控制在现有方法无法检测的水平(50copies/mI)，帮助患者重建免疫功能，提高了患者生存质量和存活率，大大延长了患者的寿命。有项研究对比了HAART时代前后艾滋病患者的病死率发现，HAART使HIV感染者的病死率从1996年的每年16.3人‰下降到了2005年的10人‰。以此推算，如果患者自20岁起开始接受HAART，寿命将从36.1岁延长至49.4岁。感染后采取积极的抗病毒治疗，未来的寿命约是普通人群的2/3。
所以，HAART的应用改变了HIV感染的自然史，使其成为一种可以控制的疾病。随着抗病毒药物毒副作用逐渐减少，感染者在适当的时机接受HAART，其寿命可再延长30年以上。
（作者均为上海市复旦大学附属公共卫生临床中心医生，卢洪洲为该中心副主任兼任中心感染科主任、主任医师、教授、博导；中华医学会感染病学会艾滋病专业学组副组长、上海市艾滋病诊疗中心主任；专家门诊时间：周六上午在同心路921号）
预防措施有哪些？
虽然目前接受抗病毒治疗的患者人数在不断增加，但随着每一个新病人接受抗病毒治疗的同时约有2.5个人被HIV感染，因此做好艾滋病的预防工作尤为重要。而艾滋病是一种可防的疾病。
预防措施主要包括以下几方面：
◆HIV暴露前预防 暴露前预防措施包括性安全措施的采取、性行为方式的改变、艾滋病知识宣教、男性包皮环切术以及阴道替诺福韦凝胶的使用等。
由于HIV突变迅速及靶向破坏免疫系统等特点，使得疫苗的研制甚为困难，目前尚无有效的疫苗用于HIV的预防。最近发表在《新英格兰杂志》上的一篇文章表明：恩曲他滨-替诺福韦复方制剂（Truvada，每日一次用药）用于男同性恋人群进行HIV暴露前预防的有效率为44%。
◆HIV暴露后预防 在发生HIV职业或非职业暴露后要及时采取暴露后预防措施，一般要求在24小时内预防性用药。
◆母婴传播阻断 抗病毒治疗以及避免母乳喂养可以减少胎儿及新生儿感染HIV。
◆治疗性预防 对阻断HIV感染的作用日益受到重视，即采用抗病毒治疗的方法进行HIV暴露后及母婴传播的阻断。
抗病毒治疗能抑制病毒复制、降低血液和精液等体液中的病毒载量，从而降低病毒的传染性，是预防HIV经性接触传播的有效措施。研究显示，抗病毒治疗使经异性性接触HIV感染者减少了80%。在艾滋病尚无有效抗病毒治疗的时代（1991——1995年），HIV感染者配偶受到感染的概率为10.3%，而当抗病毒治疗应用于临床后（1999——2003年）此概率降至1.9%。
加拿大学者建立了一个数学模型来评估抗病毒治疗对艾滋病防控的作用，其刊登在《柳叶刀》杂志上的研究成果倍受关注：如果推行艾滋病普遍自愿检测，阳性者立即进行抗病毒治疗，那么HIV感染者10年内将下降95%，到2050年因艾滋病死亡的人数将能从870万下降到390万，理论上10年内可消灭艾滋病。虽然这是一种数学模型，预测结果可能过于理想，但在一定程度上说明了预防性抗病毒治疗对控制艾滋病流行的重要作用。艾滋病的预防应联合采取宣教、行为干预及药物预防等多项措施综合进行。
近年来，每日艾滋病病毒感染人数已从1.4万下降至2008年的5700人，显示艾滋病流行势头有所减缓，也说明只要联合采取多种措施可以有效控制HIV的传播。
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Three magic weapons against AIDS: prevention, treatment, care
Date :2010 -12-06 of: Hong-Zhou Lu; Zhen Yan Source: Wen Wei Po
AIDS is acquired immunodeficiency syndrome (referred to as AIDS), is a human immunodeficiency virus (referred to as HIV, commonly known as the AIDS virus) caused by infectious diseases. AIDS was first in 1981 was found in male homosexuals, and then spread at an alarming rate and spread, has killed more than 2,500 people died worldwide, existing more than 3300 million HIV infected persons. December 1 this year is the first of 23 World AIDS Day, the theme of "rights, responsibilities and implement."
What are the risk factors?
The pathogen causes AIDS - HIV enters the body, mainly affects the body's immune system to attack and kill the human immune system plays an important role in CD4 + T lymphocytes, thereby undermining the body's immune function, decreased immune function so that infection occurs and then variety of opportunistic infections and tumors.
South African AIDS Conference in 2008 proposed: the prevention, treatment and care are the three magic weapons of mankind against AIDS. With the progress of the times, we need to understand AIDS, HIV infection do not think that would have an incurable disease. AIDS is preventable and treatable, once infected HIV, active follow-up and treatment can significantly prolong life and improve quality of life.
There are three main HIV transmission routes:
1, the sexual contact
AIDS infected semen or vaginal secretions of a large number of virus in sexual activity (vaginal intercourse, anal and oral sex), you can spread through genital or rectal mucosa. Genitals with venereal diseases (such as syphilis, gonorrhea, genital warts) or ulcers, can increase the risk of HIV infection. Rectal wall more prone to breakage than the vaginal wall, so the risk of anal intercourse than vaginal intercourse more dangerous. Therefore, gay men at high risk to HIV infection.
2, blood-borne
Infusion of blood products containing the HIV virus can infect HIV, including plasma, red cells, platelets and coagulation factor. Therefore, to accept blood products require long-term patients with high risk of HIV infection, such as hemophiliacs. In addition, the sharing of needles is caused by the spread of HIV through blood a way, the use of dirty needles can spread HIV from one person to another person. For example: intravenous drug users sharing needles. In addition, the use of HIV contaminated blood but was not sterilized syringes, acupuncture needles, extraction tools, beauty needles, razors, etc., are very dangerous.
3, mother to child transmission:
Pregnant women infected with HIV during pregnancy, during delivery are likely to pass HIV to the fetus, after delivery through breast-feeding also has to pass the child's risk of HIV, so HIV infection in a planned intervention in the whole birth, who has fertility To avoid breastfeeding.
Male homosexuals, intravenous drug users and multiple sexual partners are at high risk to HIV infection. At present with the worsening AIDS epidemic, AIDS is gradually from high-risk groups to the general population, the current AIDS epidemic situation is extremely grim. However, in low-and middle-income countries still have 80% of HIV infected people do not know their infection status, AIDS patients have been found only for the "tip of the iceberg."
AIDS has entered a stage can be cured
AIDS anti-viral therapy is the most basic treatment. Highly active antiretroviral therapy (referred to as HAART), commonly known as "cocktail therapy", is the proven most effective for HIV infection treatment. It consists of Chinese-American Professor He Dayi in 1995 suggested that the treatment requires at least three different kinds of drugs used in combination with the cocktail because of its preparation in the form similar to the name. Since the clinical application of HAART has AIDS morbidity and mortality has been greatly reduced.
AIDS treatment through the "dead", "refractory" and "curable" stage. 1981 to 1987, it committed to the etiology and pathogenesis of AIDS research, clinical no drugs for the treatment of AIDS, so AIDS is "dead" period. 1987 to 1996, there have been anti-retroviral drugs are marketed, but the mechanism of action of these drugs are similar, but in combination with anti-virus or ineffective, easily induced by viral drug resistance and lead to treatment failure, so the period AIDS "refractory" stage. From 1996 to now, AIDS prevention and control into the "curable stage." This is because the drugs have different mechanisms of the result come out. Currently, approved by the FDA for the treatment of AIDS drugs a total of 6 of 32 categories, including nucleoside reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors, protease inhibitors, integrase inhibitors, CCR5 inhibitors (a-receptor inhibitors), fusion inhibitors. They act on several aspects of HIV replication cycle, the optimal combination of different methods used to inhibit viral replication, increase CD4 cell counts in patients, reconstruction of immune function, so that patients can be significantly increased life expectancy, so that AIDS patients have seen long-term survival dawn.
Status and immune function in patients with clinical symptoms are deciding whether to initiate HAART treatment is considered. Determine the timing of antiretroviral therapy is a very complex issue, many factors should be taken into account, as far as possible to maximize the clinical benefit of patients. The best time to start HAART, with the point of view is constantly changing over time. When the CD4 count less than the last stand of 200 / μL when starting treatment, thus reducing the cost of treatment and drug toxicity, reduce the incidence of drug resistance, resistance to retain more choice after the second-line drugs. However, recent results support the early start of a number of anti-viral treatment, to make patients more access to immune reconstitution and reduce the incidence of opportunistic infections and AIDS-related mortality.
Thus, the present guidelines recommend starting antiretroviral treatment of AIDS patients the opportunity to:
① has AIDS-related symptoms;
② asymptomatic, CD4 <350 pieces / slightly;
③ CD4350 a / ul, but there may also be considered when the following treatment: the high viral load (> 10000), CD4 count decreased rapidly (annual reduction of> 100 / μL), high risk of cardiovascular disease, combined HBV / HCV infection, HIV-related kidney disease. Due to the early start antiviral therapy to patients with the clinical benefits of the larger, so the early start of antiviral therapy in the future may become a trend.
】 【Tips
★ adhere to laws of medication to treat the key to success.
Once patients with antiviral therapy, medication is necessary to rule on time and according to the amount, which is to ensure a good medication compliance. Because patients have been confirmed between medication compliance is the key to the success of antiretroviral therapy issues. In addition, irregular medication can also lead to viral drug resistance. In order to achieve good anti-viral treatment, the general requirements of the drug compliance of 95% or more. Simplify the program is to improve patient medication compliance is one of the important measures, including reducing the number of drug types and medication, and extend the interval between medication and so on.
★ regular follow-up monitoring is the basis for timely adjustment programs.
Those who can, in principle early stage of infection followed up once every quarter; for potential middle and late once, especially those found in patients with abnormal follow-up once a month in principle. Anti-viral treatment of AIDS patients during the follow-up to on a regular basis, through laboratory tests (CD4 cell count, viral load, blood biochemical examination, etc.) and clinical indicators for the monitoring to observe the effect of antiretroviral therapy and adverse drug reactions. Poor treatment when they were drug resistance testing, provide the basis for the replacement of second-line drugs.
Extend the life of the active treatment
Although the current HAART treatment can not completely remove HIV from the body, but it can inhibit viral replication as long as possible, to control the viral load in the existing methods can not detect the level of (50copies/mI), to help patients rebuild the immune function, increase quality of life and survival of patients, greatly extending the patient's life. One study compared the HAART era the mortality of AIDS patients before and after the discovery, HAART to HIV-infected persons per year from 1996 mortality 16.3 ‰ in 2005 down to 10 ‰. On this basis, if the patient since the age of 20 began receiving HAART, extended life expectancy from 36.1 years to 49.4 years. Infection to active antiretroviral therapy, the future life of the general population is about 2 / 3.
Therefore, HAART has changed HIV infection in the application of the natural history, making it a manageable disease. With the gradual reduction of toxic side effects of antiviral drugs, infected at the appropriate time receiving HAART, their life may be extended for more than 30 years.
(Authors are affiliated to Fudan University, Shanghai Public Health Clinical Center doctors, Zhou Lu, deputy director of the Center for Infectious Diseases, part-time director, chief physician, professor, Ph.D.; Chinese Medicine Institute of Infectious Diseases, AIDS, deputy director of Professional Studies, Shanghai director of AIDS treatment center; expert patient time: Saturday morning in a concentric Road No. 921)
What preventive measures?
Although antiretroviral therapy is increasing the number of patients, but with each new patient receiving antiretroviral treatment at the same time there are about 2.5 people were HIV infected, in AIDS prevention so important. And AIDS is a preventable disease.
Preventive measures include the following:
◆ HIV pre-exposure prophylaxis of pre-exposure prophylaxis measures, including safety measures taken, changes in sexual behavior, AIDS knowledge, missionaries, male circumcision and vaginal use of tenofovir gel.
Since the rapid and targeted mutations in HIV damages the immune system and so on, making vaccine development very difficult, at present there is no effective vaccine for HIV prevention. Recently published in the "New England Journal of Medicine" article on the show: emtricitabine - tenofovir compound (Truvada, once-daily medication) for gay people to effective HIV prevention before exposure to 44% .
◆ HIV post-exposure prophylaxis in the event of occupational exposure to HIV after occupational or non-exposure prophylaxis to take timely measures to general requirements within 24 hours of preventive medication.
◆ mother to child transmission has been interrupted antiretroviral therapy and to avoid breastfeeding can reduce infection of the fetus and newborn HIV.
◆ treatment of HIV infection prevention of the role of blocking more and more attention, that is, using the method of antiviral treatment and perinatal HIV transmission after exposure to blocking.
Antiviral therapy can suppress viral replication, lower body fluids such as blood and semen viral load, thereby reducing the infectious virus is to prevent the spread of HIV through sexual contact, and effective measures. Studies have shown that antiretroviral therapy to HIV infection through heterosexual contact were reduced by 80%. In no effective anti-viral treatment of AIDS era (1991 - 1995), HIV infection in spouses of infected persons was 10.3% probability, and when used in clinical anti-viral therapy after (1999 - 2003) The probability is reduced to 1.9%.
Canadian scholar to establish a mathematical model to assess the antiviral effect of treatment on AIDS prevention and control, which was published in "Lancet" magazine much attention on the research results: The introduction of universal voluntary HIV testing positive for anti-viral treatment immediately , then the HIV infection decreased by 95% within 10 years, by 2050 the number of deaths due to AIDS will decline from 8.7 million to 3.9 million, in theory, can be eliminated within 10 years of AIDS. Although this is a mathematical model to predict the results may be too ideal, but to a certain extent, that a preventive anti-viral treatment to control the important role of the AIDS epidemic. AIDS prevention should take joint mission, the behavior of drug prevention, intervention and integrated for a number of measures.
In recent years, the daily number of people infected with HIV fell from 14,000 in 5700 to 2008, indicating that the momentum of the AIDS epidemic has slowed, also shows that as long as the various measures taken jointly can effectively control the spread of HIV. |
