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How do people become infected with HIV?

HIV is a blood-borne virus in that it is transmitted through body fluids containing blood or plasma. Transmission of HIV can occur sexually or non-sexually through the exchange of body fluids infected with a high concentration of the virus, mainly blood, semen, vaginal secretions and breast milk. Transmission is especially effective during activities that involve "sealed penetration" i.e., anal or vaginal intercourse, and needle sharing.

HIV is transmitted through:

  • Sexual contact
  • Unprotected anal, vaginal, oral intercourse with an infected partner
  • Blood
  • Needle sharing with an infected person for any reason (injectable drug needles, steroid needles, ear piercing, tattoos)
  • Receiving a blood transfusion with infected blood (since 1985 all blood collected in the US has been screened for HIV)
  • Accidents in health (i.e. needle stick)
  • Perinatal
  • Intrauterine (during pregnancy, 0.5 - 30%)
  • Peripartum (during birth)
  • Breast feeding

HIV is a fragile virus and will not survive outside the body long enough for transmission from the air, in water or other surfaces. There is no chance of transmitting HIV through sexual activities that do not involve direct contact of semen, vaginal secretions, or blood with mucous membranes.

The AIDS virus is NOT spread through the air, in food, or by casual social contact. You cannot become infected with HIV by someone coughing or sneezing on you, by sharing cups or pencils, by swimming in a pool with an infected person, or by shaking hands, hugging or kissing an infected person. Although small amounts of HIV have been found in body fluids like saliva, feces, urine, tears, and sweat, there is little scientific evidence to suggest that HIV can spread through these body fluids.

Some people become infected with HIV the first time they get infected fluid in their bodies. Others are exposed and not infected. However, even if you are not infected by the virus after one exposure, you may still become infected by a subsequent exposure. The more times you are exposed to HIV, the greater chance of getting the infection. If you do not have HIV, you have everything to gain by protecting yourself now. If you have been infected, subsequent exposure to the virus can negatively impact your health.

How can I tell if I have HIV?

Many people do not know they have the virus and may unknowingly pass it on to others. They may look and feel fine for many years after HIV infection occurs.

You cannot tell if you are infected by how good you feel. You cannot tell if your partner is infected by how good they look. While talking to your partner is sensible, you cannot completely rely on what your partner tells you about their HIV status. A major national study has revealed that 40% of college men and 20% of college women will lie about their sexual histories in order to have sex.

The only way to know if you (or your partner) have the virus is by taking either a blood or an oral swab test called the "HIV antibody test".

What is the HIV antibody test?

What many people called the "AIDS" test is not a test for AIDS, but for the antibodies of HIV. Once infected with HIV, the immune system produces antibodies in an attempt to defend itself against HIV. The test identifies these antibodies. Therefore the test is accurately called the "HIV antibody test".

Should I be tested?

Have you:

  • Had unprotected sex?
  • Had sex with someone who may have been exposed to HIV?
  • Failed to use condoms correctly for every sex act or with every partner?
  • Shared needles?
  • Had more than one sex partner?

If you answered "yes" to any of these questions, there is a chance you could be infected with HIV. An HIV antibody test should be accurate within three months after your last potential exposure to HIV.

You also might want to get tested if you are in a committed, mutually monogamous relationship in which you and your partner want to safely engage in unprotected sex. Because of the time it takes to develop detectable levels of antibodies, the test results will only be reliable if neither of you has engaged in risky behaviors within the past three months. In addition, as has been discussed, this is only as safe as the honesty between you and your partner.

What kind of test will I have?

Accurate testing for HIV antibodies may require two different tests, the ELISA (enzyme linked immunosorbent assay) and the Western Blot. These tests can now be done using either saliva or blood.

The ELISA detects almost all persons infected with HIV within the first three months of infection. In a small number of cases the test may show the presence of infection when the test result is caused by something other than HIV (false positive). Therefore, positive ELISA screening tests are confirmed by the more specific Western Blot test before a blood or oral specimen is considered HIV positive.

What do the test results mean?

A negative test result means you do not have detectable levels of antibodies to the HIV virus. However, the immune system can take up to three months after infection to develop detectable antibodies to HIV. If you have engaged in any risky behavior during the three months prior to your test, a negative result may not be accurate and you should be retested at three months.

A negative test result does NOT mean that you are immune to AIDS or HIV, or that you cannot become infected with HIV in the future. A positive test result means that you have been infected with HIV and you can transmit the virus. A positive test is not a diagnosis of AIDS.

What are the symptoms of HIV infection?

The symptoms of HIV infection are the symptoms of the diseases that attack the body because of a weakened immune system. Most of the following symptoms are not specific to HIV infection. However, if you have any of these symptoms for long periods of time without the presence of another disease or condition, you should consult a medical provider.

  • Fever that lasts from a few days to longer than a month
  • Periods of excessive sweating, especially at night
  • Loss of appetite
  • Chronic or long lasting fatigue
  • Unexplained weight loss of more than 10% of body weight
  • Muscle and joint pain
  • Unexplained long lasting sore throat
  • Unexplained swollen lymph glands
  • Diarrhea lasting longer than a month with no other disease
  • Lingering infections

As the immune system becomes more compromised, the HIV infected person may acquire opportunistic diseases such as Kaposi's sarcoma, Pneumocystis carinii pneumonia, tuberculosis, neurological disorders such as meningitis, and herpes simplex infections. At this point, the HIV infected person is diagnosed with AIDS.

What is AIDS?

AIDS stand for Acquired Immunodeficiency Syndrome. AIDS is a serious disease caused by infection with the human immunodeficiency virus (HIV). HIV attacks the body's immune system. The healthy immune system produces white blood cells and antibodies which attack infectious agents such as viruses and bacteria that enter the body and cause disease. In a person with AIDS, HIV has entered the blood's infection fighting white blood cells and over several years has destroyed the cells. HIV can live in an infected person's body for years before any signs of illness appear. Yet, as the number of white blood cells declines, the immune system becomes less and less able to protect itself against a variety of illnesses. The infected person becomes more susceptible to opportunistic infections or cancers that attack the body and can cause death.

How is HIV infection (AIDS) treated?

The full disease state of AIDS is associated with life-threatening infectious disease and cancers. Treatment usually depends on the particular disease. It is important to seek treatment as soon as you know you are infected with the virus and before you have any visible signs of the disease. The full effects of HIV infection (AIDS) may appear 10-15 years after the original infection with the virus. As advances are made in the treatments of HIV-associated illness and immune disorders, it becomes increasingly beneficial for people infected with HIV to know early whether or not they have the disease. Early detection will allow your health care provider to advise you about health practices that may prolong your life.

If I am positive how can I prevent transmitting the virus to others?

  • Practice safer sex
  • Avoid "sharing" semen, blood, or vaginal secretion in any way
  • Tell sexual partners to be screened for HIV
  • Avoid sharing needles
  • Avoid donating blood, plasma, semen, or body parts (tissue organ donor)
  • Avoid pregnancy, or actively plan ahead after consultation with your doctors

Sources: The HIV Antibody Test, The American College Health Association; HIV Negative, American Social Health Association; "AIDS: Scientific Progress But No Cure in Sight," Chemical and Engineering News, July 5 (1993): 20-27; reviewed OHP / Duke SHC, 2003

What is the asymptomatic period for AIDS symptoms?

The asymptomatic period is the time between infection and the onset of symptoms of disease. This period between HIV infection and the onset of AIDS can vary anywhere from six months to an unknown period of time. Some people who are HIV antibody positive may never develop AIDS. CDC has stated that the average length of incubation at this time is ten to fifteen years or more, however, this number continues to change due to various factors.