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Acquired Immune Deficiency Syndrome (AIDS)/Human Immunodeficiency Virus (HIV)

What is HIV?

Human immunodeficiency virus (HIV) is the virus that is responsible for causing acquired immune deficiency syndrome (AIDS). The virus destroys or impairs cells of the immune system and progressively destroys the body's ability to fight infections and certain cancers.

In adults and adolescents, HIV is most commonly spread by sexual contact with an infected partner. Before routine screening of blood products began in 1985, a small group of children were infected with the virus by contaminated blood products. Currently, nearly all HIV infections in children under the age of 13 are from vertical transmission, which means the virus is passed to the child when they are in their mother's womb or as they pass through the birth canal. The virus has also been detected in breast milk, and can be spread by breastfeeding.

It should be noted that not every child born to an HIV-infected mother will acquire the virus. Without treatment, a woman with human immunodeficiency virus (HIV) has a one in four chance of infecting her fetus. Before preventive treatments were available, the CDC estimated that 1,000 to 2,000 infants were born with HIV infection in the U.S. each year. Now, health officials say there has been a dramatic reduction in mother-to-child, or perinatal HIV transmission rates due to antiretroviral medication treatment of the mother during pregnancy and labor and short-term treatment of the infant after birth.

How is HIV transmitted or spread?

The following are the means by which the HIV virus is spread:

  • Vertical transmission. HIV can be spread to babies born to, or breastfed by, mothers infected with the virus.

  • Sexual contact. In adults and adolescents, HIV is spread most commonly by sexual contact with an infected partner. The virus enters the body through the lining of the vagina, vulva, penis, rectum, or mouth through sexual activity.

  • Blood contamination. HIV may also be spread through contact with infected blood. However, due to the screening of blood for evidence of HIV infection, the risk of acquiring HIV from blood transfusions is extremely low.

  • Needles. HIV is frequently spread by sharing needles, syringes, or drug use equipment with someone who is infected with the virus. Transmission from patient to healthcare worker, or vice-versa, through accidental sticks with contaminated needles or other medical instruments, is rare.

No known cases of HIV/AIDS have been spread by the following:

  • Saliva

  • Sweat

  • Tears

  • Casual contact, such as sharing food utensils, towels, and bedding

  • Swimming pools

  • Telephones

  • Toilet seats

  • Biting insects, such as mosquitoes

How is human immunodeficiency virus (HIV) diagnosed?

The Institute of Medicine, the American College of Obstetricians and Gynecologists, the American Academy of Pediatrics, and other health organizations recommend HIV testing of all pregnant women.

Some people may develop a flu-like illness within a month or two after exposure to the HIV virus, although many people do not develop any symptoms at all when they first become infected. Many people mistake this flu-like illness as being caused by something else. Persistent or severe symptoms may not surface for 10 years or more, after HIV first enters the body in adults, or within two years in children born with an HIV infection.

Treatment of human immunodeficiency virus

Prenatal care that includes HIV counseling, testing, and treatment for infected mothers and their children saves lives and resources. Current recommendations are for HIV-positive women to take specific medications during pregnancy and during labor. Blood tests are also performed to check the amount of virus.

Newborn babies of HIV-positive mothers may also receive medication. Studies have found that giving a mother antiretroviral medications during pregnancy, labor, and delivery can reduce the chance of transmission of HIV to the baby to less than 2 percent.

Cesarean delivery may be recommended for HIV-positive women. This also helps reduce the risk of transmission of the virus to the baby, especially when the mother receives medications. HIV may also be transmitted through breast milk. Because breast milk contains the virus, HIV-positive should not breastfeed their babies.