Battling AIDS

By Claudia Wallis

There were intriguing new theories and more grim statistics, puzzling observations and enlightening discoveries. "Never before in the history of medicine has so much been learned about an entirely new disease in so short a time," pronounced Health and Human Services Secretary Margaret Heckler last week at the opening session of the most comprehensive conference yet held on the fearful subject of acquired immunodeficiency syndrome. The AIDS conference, jointly sponsored in Atlanta by the World Health Organization and HHS, drew more than 2,000 researchers, health officials, gay activists and others from points as distant as Zaire. As they swapped information in a blizzard of presentations, pamphlets and informal corridor exchanges, the dimensions and nature of the devastating disease came into sharper focus. Among the newer revelations:

One million Americans may have already been exposed to the AIDS virus, though no one yet knows what percentage of those infected will actually develop the disease.

Haitians should no longer be included among the high-risk groups for AIDS. Researchers now believe that many Haitians who contracted AIDS did so as a result of homosexual activity, use of contaminated intravenous needles or sexual contact with infected prostitutes. Denouncing their misclassification as agents of the disease, Dr. Serge Augustin of the Haitian Coalition on AIDS said, "Three years of stigmatization cannot be erased."

The AIDS virus apparently can cause serious harm to the brain and nervous system in addition to wiping out the immune system. At least 50% of AIDS patients suffer from such symptoms as loss of memory, impaired ability to speak and think, even outright dementia.

Researchers have now identified the outer protein coat of the virus, a necessary step in developing a vaccine. But an actual vaccine remains a distant prospect.

So far, 9,600 Americans have contracted AIDS, says Dr. James Curran, director of the AIDS task force at Atlanta's Centers for Disease Control, and he adds, "It'll get worse." CDC officials expect the number to double by this time next year. The epidemic is spreading worldwide. W.H.O. officials report that Paris has almost the same incidence as Los Angeles. The vast majority of AIDS cases--about 73% in the U.S.--have occurred in homosexual or bisexual men. Researchers think that the virus can remain latent for years before causing symptoms, so that people infected five or more years ago may still run the risk of developing the disease.

Health experts believe that screening tests, approved earlier this year, will help stop the spread of AIDS through contaminated blood (142 Americans have contracted AIDS from blood transfusions). The tests, recently put into use at blood banks throughout the U.S., are less than perfect, however. Researchers fear that some infected blood samples could slip through undetected. Says Curran: "We don't know how big a problem that is."

A larger threat to the general public could be the rising number of prostitutes exposed to the AIDS virus, many of whom are infected through drug abuse. Though much has been made of the role of anal intercourse in the transmission of AIDS among homosexuals, the AIDS virus is almost certainly spread through vaginal intercourse as well. The vulnerability of prostitutes raises the specter of a major new source of contagion.

On a brighter note, casual contact with AIDS victims, even over long periods of time, seems relatively safe. Newark Pediatrician James Oleske studied the foster families of nine newborns infected with AIDS and found that none of the foster mothers or siblings showed any signs of infection. Other research presented in Atlanta offered an intriguing clue to the mystery of how AIDS began. Dr. Myron Essex of the Harvard School of Public Health believes that the virus may have originated in a species known as the African green monkey and spread to humans only in recent decades. Essex has found that about 70% of African greens studied by his lab show signs of infection with a virus closely related to that which causes AIDS in humans. The monkeys, he notes, abound in the very regions of central Africa where human AIDS is believed to have begun. "I'm told they hang around settlements almost the way that bears hang around picnic grounds in national parks, trying to scavenge food, sometimes fighting and biting people."

The green monkey may be more than a clue to AIDS' past, says Essex; it may hold a key to future treatment. Despite evidence of infection with an AlDS-like virus, the monkeys are perfectly healthy. This is not true of rhesus monkeys, which develop AlDS-like symptoms when infected. Says Essex: "The African greens may have evolved a mechanism to control the virus." This mechanism of immunity, once understood, could help scientists in their all-out battle, particularly in the search for a vaccine. Nonetheless, most researchers believe that AIDS will remain a threat for decades. Says Peter Fischinger of the National Cancer Institute: "We have here a very tough opponent." --By Claudia Wallis. Reported by Christine Gorman and B. Russell Leavitt/Atlanta

With reporting by Reported by Christine Gorman, B. Russell Leavitt/Atlanta