- How does HIV and AIDS cause illness?
- What is AIDS?
- How do people get HIV?
- Who can get HIV?
- What tests are used in the diagnosis of HIV?
- Who should be tested for HIV?
- What are HIV symptoms and signs?
- What are AIDS symptoms and signs?
- What infections do people with AIDS get?
- How is AIDS diagnosed?
- What is the treatment for HIV?
- How do I know if my HIV treatments are working?
- How can I keep from getting HIV?
- How can I prevent HIV from progressing to AIDS?
- What is the prognosis for someone with HIV or AIDS?
Human immunodeficiency virus, or HIV, is the virus that causes acquired immune deficiency syndrome (AIDS). The virus weakens a person's ability to fight infections and cancer. People with HIV are said to have AIDS when they develop certain infections or cancers or when their CD4 count is less than 200. CD4 (T-cell) count is determined by a blood test in a doctor's office.
Having HIV does not always mean that you have AIDS. It can take many years for people with the virus to develop AIDS. HIV and AIDS cannot be cured. However with the medications available today, it is possible to have a normal lifespan with little or minimal interruption in quality of life. There are ways to help people stay healthy and live longer.
How Does HIV and AIDS Cause Illness?
HIV attacks and destroys a type of white blood cell called a CD4 cell, commonly called the T-cell. This cell's main function is to fight disease. When a person's CD4 cell count gets low, they are more susceptible to illnesses.
What Is AIDS?
AIDS is the more advanced stage of HIV infection. When the immune system CD4 cells drop to a very low level, a person's ability to fight infection is lost. In addition, there are several conditions that occur in people with HIV infection with this degree of immune system failure -- these are called AIDS-defining illnesses.
According to the CDC, 1,051,875 people in the U.S. have been diagnosed with AIDS since the disease was first diagnosed in 1981. They also estimate that 583,298 have died from the disease in the U.S.
How Do People Get HIV?
A person gets HIV when an infected person's body fluids (blood, semen, fluids from the vagina or breast milk) enter his or her bloodstream. The virus can enter the blood through linings in the mouth, anus, or sex organs (the penis and vagina), or through broken skin.
Both men and women can spread HIV. A person with HIV can feel OK and still give the virus to others. Pregnant women with HIV also can give the virus to their babies.
Common ways people get HIV:
- Sharing a needle to take drugs
- Having unprotected sex with an infected person
You cannot get HIV from:
- Touching or hugging someone who has HIV/AIDS
- Public bathrooms or swimming pools
- Sharing cups, utensils, or telephones with someone who has HIV/AIDS
- Bug bites
Who Can Get HIV?
Anyone can get HIV if they engage in certain activities. You may have a higher risk of getting HIV if you:
- Have unprotected sex. This means vaginal or anal intercourse without a condom or oral sex without a latex barrier with a person infected with HIV.
- Share needles to inject drugs or steroids with an infected person. The disease can also be transmitted by dirty needles used to make a tattoo or in body piercing.
- Receive a blood transfusion from an infected person. This is very unlikely in the U.S. and Western Europe, where all blood is tested for HIV infection.
- Are born to a mother with HIV infection. A baby can also get HIV from the breast milk of an infected woman.
If you fall into any of the categories above, you should consider being tested for HIV.
Health care workers are at risk on the job and should take special precautions. Some health care workers have become infected after being stuck with needles containing HIV-infected blood or less frequently, after infected blood comes into contact with an open cut or through splashes into the worker's eyes or inside their nose.
HIV Tests
The only way to know if you have HIV is to take an HIV test. Most tests looks for signs of HIV in your blood. A small sample of blood is taken from your arm. The blood is sent to a lab and tested for HIV. There are other tests available that check for HIV in the urine and oral fluid. The urine test is not very sensitive. There are currently two FDA-approved oral fluid tests. They are OraSure and OraQuick Advance.
Because of the inaccurate results, the FDA has not approved any of the home-use HIV tests which allow people to interpret their tests in a few minutes at home. There is however a Home Access test approved which can be found at most drugstores. In this test blood from a finger prick is placed on a card and sent to a licensed lab. Consumers are given an identification number to use when phoning for results and have the opportunity to speak with a counselor if desired.
Clinics that do HIV tests keep your test results secret. Some clinics even perform HIV tests without ever taking your name (anonymous testing). You must go back to the clinic to get your results. A positive test means that you have HIV. A negative test means that no signs of HIV were found in your blood.
Before taking an HIV test:
- Ask the clinic what privacy rules it follows
- Think about how knowing you have HIV would change your life
- Ask your doctor or nurse any questions you have about HIV, AIDS or the HIV test
Who Should Be Tested for HIV?
Recently, the CDC changed testing recommendations. All adults should be screened at least once. People who are considered high risk (needle drug users, multiple sex partners, for example) should be tested more often. All pregnant women should be tested. Anyone who has sustained a needle stick or significant blood exposure from a person known to have HIV or from an unknown source should be tested, too.
Does HIV Have Symptoms?
Some people get flu-like symptoms within a month after they have been infected. These symptoms often go away within a week to a month. A person can have HIV for many years before feeling ill.
As the disease progresses, both women and men may experience yeast infections on the tongue (thrush), and women may develop severe vaginal yeast infections or pelvic inflammatory disease. Shingles is often seen early on, often before someone is diagnosed with HIV.
What Are the Symptoms of AIDS?
Signs that HIV is turning into AIDS include:
- A fever that won't go away
- Sweating while you sleep
- Feeling tired all the time (not from stress or lack of sleep)
- Feeling sick all the time
- Losing weight
- Swollen glands (neck, groin, or underarms)
- Oral thrush
What Infections Do People With AIDS Get?
People with AIDS are extremely vulnerable to infection, called AIDS-defining illnesses, and often exhibit the following conditions:
- Kaposi's sarcoma, a skin tumor that looks like dark or purple blotches on the skin or in the mouth
- Mental changes and headaches caused by to fungal infections or tumors in the brain and spinal cord
- Shortness of breath and difficulty breathing because of infections of the lungs
- Dementia
- Severe malnutrition
- Chronic diarrhea
How Is AIDS Diagnosed?
If a person with HIV infection has a CD4 count that drops below 200 -- or if certain infections appear (AIDS-defining illnesses) -- that person is considered to have AIDS.
How Is HIV Treated?
We've come a long way from the days when diagnosis with HIV equaled a death sentence. Today, there are a variety of treatments that, when used in combination can significantly slow down and in some cases stop altogether, the progression of HIV infection.
After HIV infection is confirmed, your doctor will start you on a drug regimen consisting of several drugs; combinations of different types of anti-HIV drugs sometimes are called HAART, for highly-active antiretroviral therapy (HIV is a kind of virus called a retrovirus).
Taking HAART therapy is very manageable yet isn't necessarily easy. These drugs must be taken at the right time, every single day. Also, a range of side effects may occur, including: diarrhea, nausea, rash, vivid dreams, or abnormal distribution of body fat. And, especially if medications are taken incorrectly or inconsistently, the virus can mutate, or change, into a strain resistant to treatment. The good news is that there are now several HIV medications that are only taken once a day. If there is resistant virus, however, these may not work and other medication options must be used.
If your disease has progressed to AIDS, your treatment may also include drugs to combat and prevent certain infections.
How Do I Know if the HIV Treatments Are Working?
Your doctor can monitor how well your HIV treatment is working by measuring the amount of HIV in your blood (also called the viral load.) The goal of treatment is to get the viral load undetectable on labs tests; ideally less than 20 copies. This does not mean the virus is gone or cured, it means the medication is working and must be continued.
How Can I Keep From Getting HIV?
The best way to protect yourself from HIV is to avoid activities that put you at risk. There's no way to tell by looking at someone if he or she has HIV. Always protect yourself.
- Use latex condoms (rubbers) whenever you have any type of sex (vaginal, anal, or oral).
- Don't use condoms made from animal products.
- Use water-based lubricants. Oil-based lubricants can weaken condoms.
- Never share needles to take drugs.
- Avoid getting drunk or high. People who are drunk or high may be less likely to protect themselves.
How Can I Prevent HIV From Progressing to AIDS?
You can help prolong your life by taking good care of yourself and developing a good relationship with an experienced doctor specializing in HIV and AIDS. Also, be consistent about taking your HIV medications as prescribed and getting regular lab work to catch any problems early.
What Is the Outlook for Someone With HIV or AIDS?
It depends on if that person is on treatment and how the virus responds to early treatment. When treatment fails to decrease the replication of the virus, the effects can become life threatening, and the infection can progress to AIDS.
Even with treatment, some people seem to naturally experience a more rapid course towards AIDS. However, the majority of HIV patients who receive appropriate treatment do well and live healthy lives for years.
For more information, contact the CDC National AIDS Hotline: 1 (800) CDC-INFO (232-4636).
WebMD Medical Reference

QUESTION
What is HIV? See AnswerHealth Solutions From Our Sponsors
The Centers for Disease Control and Prevention. National HIV Testing Resources. FDA web site.
Reviewed by Kimball Johnson, MD on August 13, 2012
© 2012 WebMD, LLC. All rights reserved.
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