HIV的各个阶段

当人们感染 HIV 且没有接受治疗时，他们通常会经历三个不同的病程阶段。治疗 HIV 的药物，称为抗逆转录病毒疗法（ART），如果每天正确服用，可以帮助人们在所有阶段控制病情。治疗可以减缓或防止病程从一个阶段进展到下一个阶段。它还可以显著降低将 HIV 传播给他人的风险。

阶段 1：急性 HIV 感染

感染 HIV 后的 2 到 4 周内，人们可能会经历类似流感的症状，这种症状可能持续几周。这是身体对感染的自然反应。当人们处于急性 HIV 感染期时，血液中病毒量很大，并且非常具有传染性。然而，处于急性感染期的人通常并不知道自己已被感染，因为他们可能并不会立刻感到生病，甚至可能根本没有症状。要确认是否处于急性感染期，需要进行第四代抗体/抗原测试或核酸（NAT）测试。如果你认为自己因性行为或吸毒而暴露于 HIV 且有类似流感的症状，应该寻求医疗帮助并请求进行急性感染的检测。

阶段 2：临床潜伏期（HIV 不活跃或休眠期）

这一阶段有时被称为无症状 HIV 感染或慢性 HIV 感染。在这一阶段，HIV 仍然活跃，但复制速度非常慢。此时，人们可能没有任何症状，也不会生病。对于那些未接受 HIV 治疗的人来说，这个阶段可以持续十年或更长时间，但也有些人可能会更快地进入下一阶段。对于那些正确服用 ART 的人来说，这个阶段可以持续数十年。值得记住的是，即使处于这一阶段，人们仍然可以将 HIV 传播给他人，尽管那些服用 ART 并保持病毒抑制（血液中的病毒水平非常低）的人，比那些未能保持病毒抑制的人传播 HIV 的可能性要小得多。在这一阶段的末期，个体的病毒载量开始上升，CD4 细胞数量开始下降。随着病毒水平在体内的增加，个体可能会出现症状，并进入第 3 阶段。

阶段 3：获得性免疫缺陷综合症（AIDS）

AIDS 是 HIV 感染的最严重阶段。感染了 AIDS 的人的免疫系统严重受损，以至于他们会感染越来越多的严重疾病，称为机会性感染。

如果没有治疗，AIDS 患者通常能够存活大约 3 年。AIDS 的常见症状包括寒战、发热、盗汗、淋巴结肿大、虚弱和体重减轻。AIDS 的诊断标准为 CD4 细胞计数降至 200 个/mm 或以下，或者如果出现某些机会性感染。AIDS 患者可能有较高的病毒载量，并且非常具有传染性。

What are the stages of HIV?

When people get HIV and don’t receive treatment, they will typically progress through three stages of disease. Medicine to treat HIV, known as antiretroviral therapy (ART), helps people at all stages of the disease if taken the right way, every day. Treatment can slow or prevent progression from one stage to the next. It can also dramatically reduce the chance of transmitting HIV to someone else.

Stage 1: Acute HIV Infection

Within 2 to 4 weeks after infection with HIV, people may experience a flu-like illness, which may last for a few weeks. This is the body’s natural response to infection. When people have acute HIV infection, they have a large amount of virus in their blood and are very contagious. But people with acute infection are often unaware that they’re infected because they may not feel sick right away or at all. To know whether someone has acute infection, either a fourth-generation antibody/antigen test or a nucleic acid (NAT) test is necessary. If you think you have been exposed to HIV through sex or drug use and you have flu-like symptoms, seek medical care and ask for a test to diagnose acute infection.

Stage 2: Clinical Latency (HIV Inactivity or Dormancy)

This period is sometimes called asymptomatic HIV infection or chronic HIV infection. During this phase, HIV is still active but reproduces at very low levels. People may not have any symptoms or get sick during this time. For people who aren’t taking medicine to treat HIV, this period can last a decade or longer, but some may progress through this phase faster. People who are taking medicine to treat HIV (ART) the right way, every day may be in this stage for several decades. It’s important to remember that people can still transmit HIV to others during this phase, although people who are on ART and stay virally suppressed (having a very low level of virus in their blood) are much less likely to transmit HIV than those who are not virally suppressed. At the end of this phase, a person’s viral load starts to go up and the CD4 cell count begins to go down. As this happens, the person may begin to have symptoms as the virus levels increase in the body, and the person moves into Stage 3.

Stage 3: Acquired Immunodeficiency Syndrome (AIDS)

AIDS is the most severe phase of HIV infection. People with AIDS have such badly damaged immune systems that they get an increasing number of severe illnesses, called opportunistic infections.

Without treatment, people with AIDS typically survive about 3 years. Common symptoms of AIDS include chills, fever, sweats, swollen lymph glands, weakness, and weight loss. People are diagnosed with AIDS when their CD4 cell count drops below 200 cells/mm or if they develop certain opportunistic illnesses. People with AIDS can have a high viral load and be very infectious.