Many people will not have any symptoms when they first become infected with HIV. They may, however, have a flu-like illness within a month or two after exposure to the virus. This illness may include
These symptoms usually disappear within a week to a month and are often mistaken for those of another viral infection. During this period, people are very infectious, and HIV is present in large quantities in genital fluids.
More persistent or severe symptoms may not appear for 10 years or more after HIV first enters the body in adults, or within 2 years in children born with HIV infection. This period of asymptomatic infection varies greatly in each person. Some people may begin to have symptoms within a few months, while others may be symptom-free for more than 10 years.
Even during the asymptomatic period, the virus is actively multiplying, infecting and killing cells of the immune system. The virus can also hide within infected cells and be inactive. The most obvious effect of HIV infection is a decline in the number of CD4 positive T (CD4+) cells found in the blood -- the immune system's key infection fighters. The virus slowly disables or destroys these cells without causing symptoms.
As the immune system becomes more debilitated, a variety of complications start to take over. For many people, the first signs of infection are large lymph nodes, or swollen glands, that may be enlarged for more than 3 months. Other symptoms often experienced months to years before the onset of AIDS include
Some people develop frequent and severe herpes infections that cause mouth, genital, or anal sores, or a painful nerve disease called shingles. Children may grow slowly or get sick frequently.
This article was provided by U.S. National Institute of Allergy and Infectious Diseases. It is a part of the publication Understanding HIV/AIDS.