What is HIV?
HIV (human immunodeficiency virus) is a virus that damages the body’s immune system. This makes it harder to fight off germs and common illnesses. Untreated HIV can lead to AIDS (acquired immunodeficiency syndrome).
At that point, the immune system is too weak to successfully respond against other diseases, infections, and conditions.
People with HIV are prone to get sick from things that don’t affect any other person. And someone with AIDS also tend to get serious infections or cancers.
If not treated, life expectancy with end stage AIDS is about 3 years
Although there’s currently no cure, with proper medical care the virus can be controlled. Effective treatment can slow or stop the progress of HIV. Many people who treat HIV live long, healthy lives and never develop AIDS.
What is AIDS?
AIDS is a disease that can develop in people with HIV. It’s the most advanced stage of HIV. But just because a person has HIV doesn’t mean AIDS will develop.
HIV kills CD4 cells. Healthy adults generally have a CD4 count of 500 to 1,600 per cubic millimeter. A person with HIV whose CD4 count falls below 200 per cubic millimeter will be diagnosed with AIDS.
A person can also be diagnosed with AIDS if they have HIV and develop an opportunistic infection or cancer that’s rare in people who don’t have HIV.
An opportunistic infection such as Pneumocystis jiroveci pneumonia is one that only occurs in a severely immunocompromised person, such as someone with advanced HIV infection (AIDS).
Untreated, HIV can progress to AIDS within a decade.
This may be shorter if the person develops a severe opportunistic illness. However, treatment with antiretroviral drugs can prevent AIDS from developing.
If AIDS does develop, it means that the immune system is severely compromised, that is, weakened to the point where it can no longer successfully respond against most diseases and infections.
That makes the person living with AIDS vulnerable to a wide range of illnesses, including:
- oral thrush, a fungal condition in the mouth or throat
- cytomegalovirus (CMV), a type of herpes virus
- cryptococcal meningitis, a fungal condition in the brain
- toxoplasmosis, a brain condition caused by a parasite
- cryptosporidiosis, a condition caused by an intestinal parasite
- cancer, including Kaposi sarcoma (KS) and lymphoma
The shortened life expectancy linked with untreated AIDS isn’t a direct result of the syndrome itself. Rather, it’s a result of the diseases and complications that arise from having an immune system weakened by AIDS.
Where did HIV come from?
- HIV infection in humans came from a type of chimpanzee in Central Africa.
- The chimpanzee version of the virus (called simian immunodeficiency virus, or SIV) was probably passed to humans when humans hunted these chimpanzees for meat and came in contact with their infected blood.
- Studies show that HIV may have jumped from chimpanzees to humans as far back as the late 1800s.
- Over decades, HIV slowly spread across Africa and later into other parts of the world. We know that the virus has existed in the United States since at least the mid to late 1970s.
HIV is transmitted through bodily fluids that include:
- vaginal and rectal fluids
- breast milk
The virus isn’t transferred in air or water, or through casual contact.
Some of the ways HIV is transferred from person to person include:
- through vaginal or anal sex — the most common route of transmission
- by sharing needles, syringes, and other items for injection drug use
- by sharing tattoo equipment without sterilizing it between uses
- during pregnancy, labor, or delivery from a pregnant person to their baby
- during breastfeeding
- through “premastication,” or chewing a baby’s food before feeding it to them
- through exposure to the blood, semen, vaginal and rectal fluids, and breast milk of someone living with HIV, such as through a needle stick
The virus can also be transmitted through a blood transfusion or organ and tissue transplant. However, rigorous testing for HIV among blood, organ, and tissue donors ensures that this is very rare in the United States.
It’s theoretically possible, but considered extremely rare, for HIV to be transmitted through:
- oral sex (only if there are bleeding gums or open sores in the person’s mouth)
- being bitten by a person with HIV (only if the saliva is bloody or there are open sores in the person’s mouth)
- contact between broken skin, wounds, or mucous membranes and the blood of someone living with HIV
HIV does NOT transfer through:
- skin-to-skin contact
- hugging, shaking hands, or kissing
- air or water
- sharing food or drinks, including drinking fountains
- saliva, tears, or sweat (unless mixed with the blood of a person with HIV)
- sharing a toilet, towels, or bedding
- mosquitoes or other insects
It’s important to know that if someone living with HIV is being treated and has a persistently undetectable viral load, it’s virtually impossible to transmit the virus to another person.
The only way to know for sure whether you have HIV is to get tested. If your test is positive, you can start treatment right away. You can also take steps so you don’t spread the virus to others.
Knowing your HIV status helps you make healthy decisions to prevent getting or transmitting HIV.
There are three types of HIV tests:
Antibody test. This looks for antibodies — proteins your body makes to fight the virus. The test uses a small blood sample from a vein in your arm or finger stick. It can also use fluid from inside your mouth (oral fluid test). Finger stick and oral fluid tests are called rapid tests because you get the results in about 30 minutes or less.
Antigen/antibody test. This is the recommended test for HIV. It checks for HIV antibodies as well as parts of the virus called antigens.
Nucleic acid test (NAT). This looks for traces of HIV in your blood. Your blood is sent to a lab for testing, so it may take a few days to get the result
There is a self-test, also known as a home test. OraQuick is a rapid antibody test you can take at home. You swab your gums to get a fluid sample and use the kit to test it. Results are ready in about 20 minutes. It’s important to use the test correctly or it won’t work well. If this happens, you can try another home test or go to a testing center. As for the self-test’s effectiveness, clinical studies show that the test may mistakenly tell 1 out of 12 HIV-positive people that they don’t have the virus. And for every 5,000 people who don’t have HIV, the results may falsely tell 1 person that they do have it. An at-home test that shows HIV should always be confirmed by another test taken at a doctor’s office, clinic, or testing center.
Some people have flu-like symptoms within 2 to 4 weeks after infection (called acute HIV infection). These symptoms may last for a few days or several weeks. Possible symptoms include:
- night sweats
- muscle aches
- sore throat
- swollen lymph nodes
- mouth ulcers
But some people may not feel sick during acute HIV infection. These symptoms aren’t an indication that you have HIV. Other illnesses can cause these very symptoms.
When people with HIV don’t get treatment, they typically progress through three stages. But HIV medicine can slow or prevent progression of the disease. With the advancements in treatment, progression to Stage 3 is less common today than in the early days of HIV.
Stage 1: Acute HIV Infection
- People have a large amount of HIV in their blood. They are very contagious.
- Some people have flu-like symptoms. This is the body’s natural response to infection.
- But some people may not feel sick right away or at all.
- If you have flu-like symptoms and think you may have been exposed to HIV, seek medical care and ask for a test to diagnose acute infection.
- Only antigen/antibody tests or nucleic acid tests (NATs) can diagnose acute infection.
Stage 2: Chronic HIV Infection
- This stage is also called asymptomatic HIV infection or clinical latency.
- HIV is still active but reproduces at very low levels.
- People may not have any symptoms or get sick during this phase.
- Without taking HIV medicine, this period may last a decade or longer, but some may progress faster.
- People can transmit HIV in this phase.
- At the end of this phase, the amount of HIV in the blood (called viral load) goes up and the CD4 cell count goes down. The person may have symptoms as the virus levels increase in the body, and the person moves into Stage 3.
- People who take HIV medicine as prescribed may never move into Stage 3.
Stage 3: Acquired Immunodeficiency Syndrome (AIDS)
- 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.
- People receive an AIDS diagnosis when their CD4 cell count drops below 200 cells/mm, or if they develop certain opportunistic infections.
- People with AIDS can have a high viral load and be very infectious.
- Without treatment, people with AIDS typically survive about three years.
Things have come a long way from the days when there were no treatments for HIV. Today, antiretroviral therapy (ART) can slow down and sometimes stop the progress of the virus, no matter how long you’ve had it.ART works by lowering your viral load, which is the amount of HIV in your body. The goal is to get it so low that a lab test can’t detect it. With an undetectable viral load, your overall health improves, and you can’t spread the virus to others.You usually take a combination of at least three HIV meds (called antiretrovirals, or ARVs). Some come in a single pill. It’s important to take them at the right time every day, just as your doctor prescribes.
If you skip doses or go off treatment, your viral load goes up, and so does your ability to infect others.
There are seven types or classes of ARVs, which block HIV in different ways:
Nucleoside reverse transcriptase inhibitors (NRTIs) and non-nucleoside transcriptase inhibitors (NNRTIs) block an enzyme called reverse transcriptase. HIV uses this enzyme to make copies of itself.
Protease inhibitors and integrase inhibitors block other copy-making enzymes.
Entry inhibitors (fusion inhibitors, CCR5 antagonists, and post-attachment inhibitors) stop HIV from getting into CD4 cells.You usually have blood tests 1 month and 3-6 months after you start treatment. These check your viral load and CD4 levels. In time, your viral load should go down and your CD4 count should go up. This means that though you still have the virus, your treatment’s working, and you should stick with it.
HIV Treatment Side Effects
Like all drugs, ART can cause side effects. These vary, depending on the person and type of treatment. Even people taking the same HIV drugs can have different side effects. The most common are:
- nausea and vomiting
- trouble sleeping
You’re more likely to have these symptoms when you first start treatment, and some may go away in a few weeks. Other side effects can happen over time, including:
- risk of heart attack or stroke
- kidney disease
- bone loss
- weight gain
Today, more tools than ever are available to prevent HIV. You can use strategies such as abstinence (not having sex), never sharing needles, and using condoms the right way every time you have sex. You may also be able to take advantage of HIV prevention medicines such as pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP). If you have HIV, there are many actions you can take to prevent transmitting HIV to others.