Acquired immunodefiency syndrome, or AIDS, is a disease that’s caused by the virus known as HIV. This virus can be spread through the sexual fluids, blood, and breast milk of infected people. AIDS is the most advanced stage of HIV infection.
While almost everyone has heard of AIDS, many people aren’t quite sure exactly how it affects the body. We’d like to answer some frequently asked questions about this potentially deadly virus. HIV affects what part of the body? What happens to cause an HIV infection to become AIDS? How long does it take for a person to die from AIDS?
The cell affected by HIV is a certain type of cell in the immune system known as a CD4 T-cell, or simply CD4 cell. These cells are also known as “helper” cells. They act to trigger the body’s immune response. The immune system’s ability to respond to viruses, bacteria, and other invading organisms is dependent upon CD4 cells.
HIV enters CD4 cells and destroys them. As a result, the body gradually loses the ability to trigger an immune response. Even though other cells of the immune system are still present, without CD4 cells, it’s like they’re blind. They aren’t able to target and mount an effective immune response.
Soon after a person is first infected with HIV, they will often experience a flu-like illness. As the levels of the virus in the blood spike very high, the patient may feel general symptoms of illness, like malaise (a feeling of being very tired) and fever. Some people have other symptoms, like a rash, diarrhea, or a cough. However, the symptoms of this early stage may be very mild, and many patients don’t even notice them at all.
This flu-like illness will pass, as the body is able to reduce the levels of virus in the blood to very low levels. Many people believe that they simply had the flu. However, even though HIV levels are now too low to cause symptoms, the virus is slowly destroying the immune system. At this point, the virus has entered a phase called clinical latency, or the chronic phase of HIV infection.
Once the virus has caused enough damage to the immune system, then the person will start to get opportunistic infections. These are infections with viruses, bacteria, molds, and other organisms that a healthy immune system would normally fight off easily. Certain types of cancers also become more likely; these cancers are caused by certain viruses that would normally be fought off by the immune system.
At first, the person may begin to develop relatively mild infections. Later, as more of the immune system is destroyed, the person begins to be infected by more organisms, and the infections are more severe. Once the CD4 count has dropped below 200 and/or the person has developed a certain number of infections, then they’re considered to be in stage 3 HIV infection, which is also known as AIDS.
Ultimately, death from AIDS actually happens due to these other infections that the body can no longer fight off, rather than from HIV itself. AIDS affects the entire body, through the various infections that it allows in.
The early phase occurs approximately two weeks to a month after a person is exposed to HIV, and lasts only a few days to weeks. Once the early phase has passed, the person enters the phase of clinical latency, when there are generally no HIV progression symptoms. This phase usually lasts about eight to ten years, but it can be even longer.
Once the CD4 count has dropped below 200 and the person has AIDS, the average time that they are expected to live is about three years. This can vary significantly, because it depends on what infections they’re exposed to. Ultimately, they will die from one or more of these infections.
It’s important to mention that most HIV-positive people in the US don’t ever develop AIDS. This is because there are medications available that are very effective at controlling HIV. These medications are known as antiretroviral therapy, or ART. When people take these medications regularly, this will generally prevent HIV from progressing.
People who take ART can have a relatively normal life expectancy, and can live for many decades without progressing to AIDS. However, they can still spread HIV, even if the level of virus in their blood is very low or undetectable.
It’s best to start ART as early as possible in the course of the infection, before the virus has had a chance to destroy many CD4 cells. However, because of the lack of early symptoms, many people aren’t aware that they’ve been infected. The only way to find out whether you’ve been exposed to HIV is to get tested
Most people with HIV have no symptoms at all for many years. After the initial flu-like illness, patients with HIV almost never have any symptoms for the next few years. This is part of what makes HIV so dangerous. Many people with HIV have no idea that they have it, but they can still spread is the only way to know whether you have HIV.
It’s often a period of many years between becoming infected with HIV and showing significant symptoms. If someone gets infected with HIV and doesn’t get treatment, then it takes about ten years or so before they begin to show serious symptoms (beyond the often mild symptoms of the early phase).
Once the virus has destroyed the immune system enough, then the patient will start to get opportunistic infections. In a person with AIDS, the infected immune system may suddenly become incapable of preventing a wide variety of diseases, and the person can get many infections in a short period of time. This is why it can seem like the symptoms of HIV have developed all at once, even though the person has actually had HIV for years.
HIV is known to be transmitted through the sexual fluids, blood, and breast milk of infected people. Any type of unprotected sexual contact can spread the virus, including vaginal, anal, or oral sex. Sharing needles or otherwise allowing the blood of one person into another person’s body can also spread it. In addition, the virus can be passed from mother to baby during pregnancy or breastfeeding.
HIV. Centers for Disease Control and Prevention (2021). https://www.cdc.gov/hiv/default.html. Accessed 20 March 2022.
HIV/AIDS. Mayo Clinic (2020). https://www.mayoclinic.org/diseases-conditions/hiv-aids/symptoms-causes/syc-20373524. Accessed 20 March 2022.
HIV and AIDS. National Health Service (2021). https://www.nhs.uk/conditions/hiv-and-aids/. Accessed 20 March 2022.
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