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HIV's Early Warnings

A new study in India shows that people newly infected with the AIDS virus experience fever, joint pain, and night sweats weeks before conventional blood tests can detect the infection. The study, reported in tomorrow's issue of the Journal of the American Medical Association, points to two other early tip-offs to possible HIV infection: genital ulcers and recent unprotected sex with prostitutes.

The worldwide AIDS epidemic is raging more furiously in India than in any other country, with as many as 5 million people infected, according to the World Health Organization. A team from three organizations--the National Institute of Allergy and Infectious Diseases (NIAID), the Johns Hopkins University School of Hygiene and Public Health, and the National AIDS Research Institute in Pune, India--studied 3874 people in India to identify HIV's early warning signs and get a close look at the behaviors that are spreading the disease.

The patients were screened for p24 antigen, a core HIV protein, in a test that is much more expensive than standard antibody tests. According to Thomas Quinn of NIAID's immunoregulation laboratory, who is the study's senior author, p24 antigen can be detected in HIV-infected blood 2 to 3 weeks after infection--several weeks before HIV antibodies first appear. "With p24-antigen screening we can identify HIV infections much sooner after they occur and thus get a more accurate picture of risk factors and symptoms of acute HIV infection," he says.

The p24-positive patients consistently suffered from a collection of symptoms--fever, night sweats, and joint pain. Other symptoms, such as enlarged lymph nodes, oral thrush, diarrhea, and rash, which previous studies had linked to acute infection, were scarcer in people carrying p24. Two other characteristics stood out in the p24-positive patients: They were 50% more likely than uninfected people to have had unprotected sex with a prostitute, and they were nearly twice as likely to have an active genital ulcer.

The research provides a valuable look at the earliest signs of HIV infection, says Rod Hoff, an epidemiologist with the AIDS Division at NIAID. Early detection means treatment regimens can begin sooner. Hoff cautions, however, that the symptoms seen among the study participants could be nonrepresentative, because the studies were done on a select group of people seeking treatments for sexually transmitted diseases and the subtype of HIV may be unique.