On This Page: Causes | Risk Factors | Prevention
HIV stands for Human Immunodeficiency Syndrome, and we hope this resource will be a source of information about all aspects of the syndrome for educational purposes.
HIV (human immunodeficiency virus) is the virus that causes AIDS. It attacks the cells of your immune system, making you more vulnerable to get sick or even die from illnesses your body would normally be able to fight off. HIV is spread through sex, so condoms help protect you.
Approximately 1.1 million people in the United States are living with HIV. About 14% (1 in 7) are unaware that they are infected.1 Because many people with HIV don’t show symptoms for years after infection, getting tested is important for early detection, and it can even be lifesaving.
Although there is no cure, medication can help people with HIV have a near-normal life span and a healthy quality of life. HIV treatment can also manage the condition to help the virus become non-transmittable.
In early 2022, the first of its kind appeared in medical history, three mRNA-based vaccines against HIV. This was a trial on volunteers conducted by virologists and epidemiologists. These vaccines are meant to be for prevention, as in they are taken to prevent an individual from being infected with HIV. Currently, HIV has no cure, but this could be the first step in at least preventing further infection rates from rising.
HIV and AIDS are not the same thing. HIV is a virus that makes copies of itself and can eventually lead to the condition AIDS. Not all people with HIV have AIDS. However, anyone diagnosed with AIDS has previously contracted HIV.
AIDS stands for acquired immunodeficiency syndrome. It is the third and final stage of HIV infection when the virus has caused serious damage to the immune system. HIV destroys immune cells called CD4 cells, or T cells. You have AIDS when your CD4 cells reach a dangerously low amount (below 200 cells/mm) or if you develop opportunistic illnesses.2
When the body’s defense has deteriorated, it is no longer able to properly protect against infection or detect faulty cells. Therefore, people living with AIDS can develop opportunistic infections that the body would otherwise be able to fight off, or types of cancer.3 Learn more about AIDS symptoms on our dedicated page.
Many people with HIV or AIDS don’t show HIV symptoms right away. Because they feel fine, they don’t know they have it and might unknowingly spread the virus. Some people with HIV experience a flu-like illness within 2-4 weeks of infection, but this passes after a short time and can be easy to overlook. It can take years for someone with HIV to start feeling really sick.
You probably have a million questions about how you might catch HIV. Can HIV be transmitted through saliva or through saliva to an open wound? How much saliva is needed to transmit HIV? Is HIV transmitted through kissing? Can HIV be transmitted through oral sex? How quickly can HIV be transmitted? Can HIV be transmitted through breast milk? Can mosquitoes transmit HIV? Is HIV transmitted through mucous membranes? How is HIV trasmitted through sex or birth?
HIV can be transmitted only through certain body fluids: blood, semen, vaginal fluids, anal fluids/mucus, and breast milk. You can contract HIV if the virus enters your body through mucous membranes like the vagina, the rectum, the opening of the penis. It can also enter the body through cuts or sores on your skin.
Most commonly, HIV is spread through:
The risk of acquiring HIV depends on the type of sexual activity.6 Unprotected receptive anal sex (bottoming) is the highest-risk sexual behavior. This is because rectal tissue is thin and fragile and tearing occurs easily.7 An insertive partner (or top) can also get HIV through the urethra at the tip of the penis or through cuts or sores on the penis.
Pregnant women with HIV can pass HIV to their baby during pregnancy, labor, childbirth, or breastfeeding. Taking HIV medicine helps lower the risk of mother-child transmission and keep both the mother and baby healthy.
You can’t get HIV from:
Anyone can get HIV, regardless of sexual orientation, gender, race, or age. That being said, gay and bisexual men are the population most affected by HIV, making up more than half of the people living with HIV. The CDC recommends that sexually active men who have sex with men get tested at least once a year for HIV. Read on to see how HIV is transmitted through sex.
You may be at increased risk of getting HIV if you have:
HIV can cause infections, AIDS is a condition. Contracting HIV can develop into AIDS. Otherwise known as stage 3 HIV, AIDS happens when HIV is done heavy damage to the immune system. You can have HIV without it developing into AIDS. It all depends on how well you manage your HIV and how compromised your immune system is. AIDS is life-threatening and is meant to describe an accumulation of infections that the body is susceptible to since the immune system is no longer able to produce enough white blood cells to fight off the infections.
Without treatment, it usually takes about 8–10 years to develop AIDS after initial HIV infection.9 It can advance slower or quicker depending on factors like age and general health. HIV treatment makes it possible to slow down the progression, and some people can live with HIV without ever developing AIDS. This is why getting tested for HIV and knowing your status is so crucial.
Untreated HIV develops into AIDS, which eventually leads to death. HIV itself does not kill most people, but it compromises the immune system so that people with HIV/AIDS are more likely to die from pneumonia, diarrhoeal illnesses, brain infections, or certain tumors such as cervical lymphoma.
Without treatment, people with AIDS generally survive for about 3 years. But having HIV is not a death sentence, thanks to modern medicine. It is very important you seek treatment if you know you have HIV/AIDS so that you can manage the virus. Proper medication lowers the amount of HIV in the body and slows the virus’ progression.
There are two main types of HIV: HIV-1 and HIV-2. As with other viruses, HIV has different strains and variants. While HIV-1 and HIV-2 are different, both can lead to AIDS. HIV-1 is the most common type and accounts for around 95% of infections worldwide. HIV-2 is not commonly seen outside of West Africa, but it has been seen in other places. HIV-2 is generally less infectious and takes longer to progress to AIDS compared to HIV-1.10
No, once you have HIV, it is a lifelong infection. That being said, people living with HIV can take medicine to reduce the amount of virus in the blood and other bodily fluids. This medicine is called antiretroviral therapy (ART), and it helps you suppress the virus and stay healthy for many years. In fact, by following treatment, it is possible to achieve an undetectable viral load, meaning that viral levels are so low that tests can’t detect it. People with an undetectable viral load have effectively no risk of spreading HIV to partners during sex.
Condoms and Lubricants
You can lower your risk of getting or spreading HIV by using latex or polyurethane condoms correctly every time you have sex. Water- or silicone-based lubes can help prevent condom breakage and torn tissue during sex. Since condoms are not 100% effective, other prevention methods can further lower your risk.
PrEP stands for pre-exposure prophylaxis. It is a pill taken daily by mouth that can stop HIV from taking hold and spreading. The CDC reports that PrEP is highly effective, reducing the risk of getting HIV from sex by about 99% and reducing the risk for people who inject drugs by at least 74%.11
PEP stands for post-exposure prophylaxis. It is an antiretroviral medicine (used to treat HIV), and it is taken only in emergencies after being potentially exposed to the virus (for example, if the condom broke, you shared needles or drug equipment, or were sexually assaulted).
PEP must be started as soon as possible, within 72 hours (3 days) of a possible HIV exposure. Every hour counts, so the sooner you start PEP, the better.
Lower Risk Sexual Activities
Certain behaviors like oral sex have little to no risk of HIV transmission.12 However, oral sex can spread other STDs like herpes, syphilis, chlamydia, and gonorrhea, so it’s recommended to use protection like condoms and dental dams.
Being in a mutually monogamous relationship with someone who has tested negative or limiting your amount of sexual partners can also lower your chances of getting or spreading HIV.
By talking openly with partners and getting tested for HIV, you can protect your health. Getting tested for HIV is the only way to know for sure if you have it. If you do, knowing your status can help you get the support and treatment. The proper care and medicine can keep an HIV-positive person healthier and prolong their life.