Human Immunodeficiency Virus (HIV) Infection
Topic OverviewWhat is HIV? What is AIDS?HIV (human immunodeficiency virus) is a virus that attacks the immune system, the body's natural defense system. Without a strong immune system, the body has trouble fighting off disease. Both the virus and the infection it causes are called HIV. White blood cells are an important part of the immune system. HIV invades and destroys certain white blood cells called CD4+ cells. If too many CD4+ cells are destroyed, the body can no longer defend itself against infection. The last stage of HIV infection is AIDS (acquired immunodeficiency syndrome). People with AIDS have a low number of CD4+ cells and get infections or cancers that rarely occur in healthy people. These can be deadly. But having HIV does not mean you have AIDS. Even without treatment, it takes a long time for HIV to progress to AIDS—usually 10 to 12 years. If HIV is diagnosed before it becomes AIDS, medicines can slow or stop the damage to the immune system. With treatment, many people with HIV are able to live long and active lives. What causes HIV?HIV infection is caused by the human immunodeficiency virus. You can get HIV from contact with infected blood, semen, or vaginal fluids.
HIV doesn't survive well outside the body. So it cannot be spread by casual contact such as kissing or sharing drinking glasses with an infected person. What are the symptoms?HIV may not cause symptoms early on. People who do have symptoms may mistake them for the flu or mono. Common early symptoms include:
Symptoms may appear from a few days to several weeks after a person is first infected. The early symptoms usually go away within 2 to 3 weeks. After the early symptoms go away, an infected person may not have symptoms again for many years. Without treatment, the virus continues to grow in the body and attack the immune system. After a certain point, symptoms reappear and then remain. These symptoms usually include:
A doctor may suspect HIV if these symptoms last and no other cause can be found. Treatment usually keeps the virus under control and helps the immune system stay healthy. How is HIV diagnosed?The U.S. Food and Drug Administration (FDA) has approved tests that detect HIV antibodies in urine, fluid from the mouth (oral fluid), or blood. If a test on urine or oral fluid shows that you are infected with HIV, you will probably need a blood test to confirm the results. If you have been exposed to HIV, your immune system will make antibodies to try to destroy the virus. Blood tests can find these antibodies in your blood. Most doctors use two blood tests, called the ELISA and the Western blot assay. If the first ELISA is positive (meaning that HIV antibodies are found), the blood sample is tested again. If the second test is positive, a Western blot will be done to be sure. It may take as long as 6 months for HIV antibodies to show up in a blood sample. If you think you have been exposed to HIV but you test negative for it:
Some people are afraid to be tested for HIV. But if there is any chance you could be infected, it is very important to find out. HIV can be treated. Getting early treatment can slow down the virus and help you stay healthy. And you need to know if you are infected so you can prevent spreading the infection to other people. You can get HIV testing in most doctors' offices, public health clinics, hospitals, and Planned Parenthood clinics. You can also buy a home HIV test kit in a drugstore or by mail order. But be very careful to choose only a test that has been approved by the U.S. Food and Drug Administration (FDA). If a home test is positive, see a doctor to have the result confirmed and to find out what to do next. How is it treated?The standard treatment for HIV is a combination of medicines called highly active antiretroviral therapy (HAART). Antiretroviral medicines slow the rate at which the virus multiplies. Taking these medicines can reduce the amount of virus in your body and help you stay healthy. It may not be easy to decide the best time to start treatment. There are pros and cons to starting HAART before your CD4+ cell count gets too low. Discuss these with your doctor so you understand your choices. To monitor the HIV infection and its effect on your immune system, a doctor will do two tests:
If you have no symptoms and your CD4+ cell count is at a healthy level, you may not need treatment yet. Your doctor will repeat the tests on a regular basis to see how you are doing. If you have symptoms or some other health problems, you should start treatment, whatever your CD4+ count is. After you start treatment, it is important to take your medicines exactly as directed by your doctor. When treatment doesn't work, it is often because HIV has become resistant to the medicine. This can happen if you don't take your medicines correctly. Ask your doctor if you have questions about your treatment. Treatment has become much easier to follow over the past few years. New combination medicines include two or three different medicines in one pill. Many people with HIV get the treatment they need by taking just one or two pills a day. To stay as healthy as possible during treatment:
Learn all you can about HIV so you can take an active role in your treatment. Your doctor can help you understand HIV and how best to treat it. Also, consider joining an HIV support group. Support groups can be a great place to share information and emotions about HIV infection. How can you prevent HIV?HIV can be spread by people whether they know they are infected or not. To protect yourself and others:
Frequently Asked Questions
eMedicineHealth Medical Reference from Healthwise
This information does not replace the advice of a doctor. Healthwise disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions. To learn more visit Healthwise.org © 1995-2012 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated. |
WebMD Daily
Get breaking medical news.
From WebMD
Resources for Staying Well
Featured Centers
Health Solutions From Our Sponsors
Featured Topics
Medical Dictionary
Pill Identifier on RxList
- quick, easy,
pill identification
Find a Local Pharmacy
- including 24 hour, pharmacies

