What is HIV?

HUMAN IMMUNODEFICIENCY VIRUS (HIV)

HIV stands for human immunodeficiency virus. If left untreated, HIV can lead to the disease AIDS (acquired immunodeficiency syndrome).
Unlike some other viruses, the human body can’t get rid of HIV completely. So once you have HIV, you have it for life.
HIV attacks the body’s immune system, specifically the CD4 cells (T cells), which help the immune system fight off infections. If left untreated, HIV reduces the number of CD4 cells (T cells) in the body, making the person more likely to get infections or infection-related cancers. Over time, HIV can destroy so many of these cells that the body can’t fight off infections and disease. These opportunistic infections or cancers take advantage of a very weak immune system and signal that the person has AIDS, the last state of HIV infection.
No effective cure for HIV currently exists, but with proper treatment and medical care, HIV can be controlled. The medicine used to treat HIV is called antiretroviral therapy or ART. If taken the right way, every day, this medicine can dramatically prolong the lives of many people with HIV, keep them healthy, and greatly lower their chance of transmitting the virus to others. Today, a person who is diagnosed with HIV, treated before the disease is far advanced, and stays on treatment can live a nearly as long as someone who does not have HIV.
The only way to know for sure if you have HIV is to get tested. Testing is relatively simple. You can ask your health care provider for an HIV test. Many medical clinics, substance abuse programs, community health centers, and hospitals offer them too. You can also buy a home testing kit at a pharmacy or online.
To find an HIV testing location near you, click here.

WHERE DID
HIV COME FROM?

Scientists identified a type of chimpanzee in Central Africa as the source of HIV infection in humans. They believe that the chimpanzee version of the immunodeficiency virus (called simian immunodeficiency virus, or SIV) most likely was transmitted to humans and mutated into HIV when humans hunted these chimpanzees for meat and came into contact with their infected blood. Studies show that HIV may have jumped from apes to humans as far back as the late 1800s. Over decades, the virus 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.

HOW IS HIV SPREAD?

You can get or transmit HIV only through specific activities. Most commonly, people get or transmit HIV through sexual behaviors and needle or syringe use.
HIV is not spread easily. Only certain body fluids from a person who has HIV can transmit HIV:

  • Blood
  • Semen (cum)
  • Pre-seminal fluid (pre-cum)
  • Rectal fluids
  • Vaginal fluids
  • Breast milk

These body fluids must come into contact with a mucous membrane or damaged tissue or be directly injected into your bloodstream (by a needle or syringe) for transmission to occur. Mucous membranes are found inside the rectum, vagina, penis, and mouth.
If you think you may have been exposed to HIV, get tested. You can get tested at your healthcare provider’s office, a clinic, and other locations. You can also get a HIV home test kit from your local pharmacy. Use the AIDS.gov HIV Testing and Care Services Locator to find a testing site near you.

WAYS HIV IS TRANSMITTED

In the United States, HIV is spread mainly by:

  • Having anal or vaginal sex with someone who has HIV without using a condom or taking medicines to prevent or treat HIV.
  • Anal sex is the highest-risk sexual behavior. For the HIV-negative partner, receptive anal sex (“bottoming”) is riskier than insertive anal sex (“topping”).
  • Vaginal sex is the second highest-risk sexual behavior.
  • Sharing needles or syringes, rinse water, or other equipment (“works”) used to prepare injection drugs with someone who has HIV. HIV can live in a used needle up to 42 days depending on temperature and other factors.

Less commonly, HIV may be spread:

  • From mother to child during pregnancy, birth, or breastfeeding. Although the risk can be high if a mother is living with HIV and not taking medicine, recommendations to test all pregnant women for HIV and start HIV treatment immediately have lowered the number of babies who are born with HIV.
  • By being stuck with an HIV-contaminated needle or other sharp object. This is a risk mainly for health care workers.

In extremely rare cases, HIV has been transmitted by:

  • Oral sex—putting the mouth on the penis (fellatio), vagina (cunnilingus), or anus (rimming). In general, there is little to no risk of getting HIV from oral sex. But transmission of HIV, though extremely rare, is theoretically possible if an HIV-positive man ejaculates in his partner’s mouth during oral sex. To learn more about how to lower your risk, see CDC’s Oral Sex and HIV Risk.
  • Receiving blood transfusions, blood products, or organ/tissue transplants that are contaminated with HIV. This was more common in the early years of HIV, but now the risk is extremely small because of rigorous testing of the U.S. blood supply and donated organs and tissues.
  • Eating food that has been pre-chewed by an HIV-infected person. The contamination occurs when infected blood from a caregiver’s mouth mixes with food while chewing. The only known cases are among infants.
  • Being bitten by a person with HIV. Each of the very small number of documented cases has involved severe trauma with extensive tissue damage and the presence of blood. There is no risk of transmission if the skin is not broken.
  • Contact between broken skin, wounds, or mucous membranes and HIV-infected blood or blood-contaminated body fluids.
  • Deep, open-mouth kissing if the person with HIV has sores or bleeding gums and blood from the HIV-positive partner gets into the bloodstream of the HIV-negative partner. HIV is not spread through saliva.

HIV IS NOT SPREAD BY…

HIV does not survive long outside the human body (such as on surfaces) and it cannot reproduce outside a human host. It is not spread by:

  • Air or water
  • Mosquitoes, ticks or other insects
  • Saliva, tears, or sweat that is not mixed with the blood of an HIV-positive person
  • Shaking hands, hugging, sharing toilets, sharing dishes/drinking glasses, or closed-mouth or “social” kissing with someone who is HIV-positive
  • Drinking fountains
  • Other sexual activities that don’t involve the exchange of body fluids (for example, touching).

HIV TREATMENT REDUCES TRANSMISSION RISK

People with HIV who are using antiretroviral therapy (ART) consistently and who have achieved viral suppression (having the virus reduced to an undetectable level in the body) are very unlikely to transmit the virus to their uninfected partners. However, there is still some risk of transmission, so even with an undetectable viral load, people with HIV and their partners should continue to take steps to reduce the risk of HIV transmission.

I HAVE HIV,
DOES THAT MEAN I HAVE AIDS?

No. The terms “HIV” and “AIDS” can be confusing because both terms refer to the same disease. However, “HIV” refers to the virus itself, and “AIDS” refers to the late stage of HIV infection, when an HIV-infected person’s immune system is severely damaged and has difficulty fighting diseases and certain cancers. Before the development of certain medications, people with HIV could progress to AIDS in just a few years. But today, most people who are HIV-positive do not progress to AIDS. That’s because if you have HIV and you take ART consistently, you can keep the level of HIV in your body low. This will help keep your body strong and healthy and reduce the likelihood that you will ever progress to AIDS. It will also help lower your risk of transmitting HIV to others.

HOW CAN I TELL IF I HAVE HIV?

You cannot rely on symptoms to tell whether you have HIV. The only way to know for sure if you have HIV is to get tested. Knowing your status is important because it helps you make healthy decisions to prevent getting or transmitting HIV.
Use HIV210’s HIV Testing Locator to find a testing site near you.
The symptoms of HIV vary, depending on the individual and what stage of the disease you are in: the early stage, the clinical latency stage, or AIDS (the late stage of HIV infection). Below are the symptoms that some individuals may experience in these three stages. Not all individuals will experience these symptoms.

EARLY STAGES OF HIV

Some people may experience a flu-like illness within 2-4 weeks after HIV infection. But some people may not feel sick during this stage.
Flu-like symptoms can include:

  • Fever
  • Chills
  • Rash
  • Night sweats
  • Muscle aches
  • Sore throat
  • Fatigue
  • Swollen lymph nodes
  • Mouth ulcers

These symptoms can last anywhere from a few days to several weeks. During this time, HIV infection may not show up on an HIV test, but people who have it are highly infectious and can spread the infection to others.
You should not assume you have HIV just because you have any of these symptoms. Each of these symptoms can be caused by other illnesses. And some people who have HIV do not show any symptoms at all for 10 years or more.
If you think you may have been exposed to HIV, get an HIV test. Most HIV tests detect antibodies (proteins your body makes as a reaction against the presence of HIV), not HIV itself. But it takes a few weeks for your body to produce these antibodies, so if you test too early, you might not get an accurate test result. A new HIV test is available that can detect HIV directly during this early stage of infection. So be sure to let your testing site know if you think you may have been recently infected with HIV.
After you get tested, it’s important to find out the result of your test so you can talk to your health care provider about treatment options if you’re HIV-positive or learn ways to prevent getting HIV if you’re HIV-negative.
You are at high risk of transmitting HIV to others during the early stage of HIV infection, even if you have no symptoms. For this reason, it is very important to take steps to reduce your risk of transmission.

CLINICAL LATENCY STAGE

After the early stage of HIV infection, the disease moves into a stage called the clinical latency stage (also called “chronic HIV infection”). During this stage, HIV is still active but reproduces at very low levels. People with chronic HIV infection may not have any HIV-related symptoms, or only mild ones.
For people who aren’t taking medicine to treat HIV (called antiretroviral therapy or ART), this period can last a decade or longer, but some may progress through this phase faster. People who are taking medicine to treat HIV the right way, every day may be in this stage for several decades because treatment helps keep the virus in check. (Read more about HIV treatment.)
It’s important to remember that people can still transmit HIV to others during this phase even if they have no symptoms, 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.

PROGRESSION TO AIDS

If you have HIV and you are not on ART, eventually the virus will weaken your body’s immune system and you will progress to AIDS (acquired immunodeficiency syndrome), the late stage of HIV infection.
Symptoms can include:

  • Rapid weight loss
  • Recurring fever or profuse night sweats
  • Extreme and unexplained tiredness
  • Prolonged swelling of the lymph glands in the armpits, groin, or neck
  • Diarrhea that lasts for more than a week
  • Sores of the mouth, anus, or genitals
  • Pneumonia
  • Red, brown, pink, or purplish blotches on or under the skin or inside the mouth, nose, or eyelids
  • Memory loss, depression, and other neurologic disorders.

Each of these symptoms can also be related to other illnesses. So the only way to know for sure if you have HIV is to get tested.
Many of the severe symptoms and illnesses of HIV disease come from the opportunistic infections that occur because your body’s immune system has been damaged.

STATISTICS