HIV infection is a long-term condition caused by a virus that also can cause a life-threatening disease called AIDS.

HIV stands for human immunodeficiency virus. The virus damages the immune system. It can spread through unprotected sex, contact with infected blood and use of shared needles. It also can spread from pregnant parent to child during pregnancy, childbirth or breastfeeding. Without treatment, HIV can cause acquired immunodeficiency syndrome (AIDS).

Symptoms of HIV infection can include a flu-like illness within 2 to 4 weeks of infection. This can cause fever, aches, joint pain and rash. Once HIV treatment is started, symptoms may go away for many years. But if HIV infection leads to AIDS, symptoms can include sweats, chills, fever, diarrhea, fatigue and mouth sores. AIDS can be fatal.

Treatment for HIV infection involves taking medicines called antiretroviral therapy. The medicines can lower the amount of virus in the body. They also can lower the risk of other infections that become more likely when the immune system is weakened. If antiretroviral therapy is taken exactly as prescribed, it can help prevent AIDS.