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What Are HIV and AIDS?

  • HIV (human immunodeficiency virus) is a that attacks the immune system.
  • AIDS (acquired immune deficiency syndrome) is a late stage of HIV infection.

There's no cure for HIV/AIDS, but medicines can help people live long, healthy lives.

What Happens In HIV Infection?

HIV attacks cells in the immune system called CD4 cells (or T cells). CD4 cells help the body fight off infections and some kinds of cancers.

What Happens In AIDS?

Over time, HIV kills more and more CD4 cells, and this leads to AIDS. In AIDS, the immune system is severely weakened. Serious infections and health problems happen.

What Are the Signs & Symptoms of HIV?

Symptoms depend on what stage of HIV infection someone has.

Acute HIV infection: This is when someone is first infected with the virus. Symptoms usually start about 2–4 weeks after infection and last a few days to a few weeks. They can include fever, headache, muscle aches, swollen glands, and a rash. Some people have very mild symptoms or don’t notice any symptoms.

Chronic HIV infection: During this next stage, a person may have no symptoms or mild symptoms. People can stay in this stage for 5–10 years, but some move to the next stage (AIDS) faster.

AIDS is the most severe stage of HIV infection. Symptoms can include:

  • very fast weight loss
  • fever
  • extreme tiredness
  • swollen glands
  • a lung infection called pneumocystis pneumonia
  • diarrhea
  • sores of the mouth, anus, and genitals
  • some types of cancers
  • skin problems

How Do People Get HIV?

HIV spreads when infected blood or body fluids (such as semen or vaginal fluids) enter the body. This can happen:

  • during sex (especially anal sex and vaginal sex)
  • through sharing needles for injecting drugs or tattooing
  • by getting stuck with a needle that has an infected person's blood on it

HIV also can pass from mother to child during pregnancy, childbirth, or breastfeeding.

HIV does NOT spread through:

  • pee, poop, spit, throw-up, or sweat (as long as no blood is present)
  • coughing or sneezing
  • holding hands
  • sharing eating utensils or drinking glasses

How Is HIV Diagnosed?

Health care providers usually diagnose HIV through blood tests. Someone who has HIV is said to be "HIV positive."

Home tests also are available without a prescription at the drugstore.

How Is HIV Treated?

Most people with HIV can stay healthy by taking medicines called antiretrovirals. Antiretrovirals help lower the viral load (how much HIV is in the body) so that the CD4 count can go up.