• Fever
• Headache
• Tiredness
• Enlarged lymph nodes (glands of the immune system easily felt in the nece and groin

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 two years in children born with HIV infection. This period of "asymptomatic" infection is highly individual. 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. HIV's effect is seen most obviously in a decline in the blood levels of CD4 positive T cells (also called T4 cells) -- the immune system's key infection fighters. At the beginning of its life in the human body, the virus disables or destroys these cells without causing symptoms.

As the immune system worsens, a variety of complications start to take over. For many people, their first sign of infection is large lymph nodes or "swollen glands" that may be enlarged for more than three months. Other symptoms often experienced months to years before the onset of AIDS include

• Lack of energy
• Weight loss
• Frequent fevers and sweats
• Persistent or frequent yeast infections (oral or vaginal)
• Persistent skin rashes or flaky skin
• Pelvic inflammatory disease in women that does not respond to treatment
• Short-term memory loss