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STRANGE TRIP BACK TO THE FUTURE

Officially, the AIDS epidemic began in the U.S. in 1981. Recently, however, researchers jolted the medical community with evidence that the disease may have made its first appearance in the U.S.


almost 15 years earlier. In a front-page article in the Chicago "Tribune", they related the extraordinary saga of Robert R., a 16-year-old black Missourian who, they believe, died of AIDS in 1969. The case may represent the earliest documented instance of AIDS in North America, predating that of Gaetan Dugas, a Canadian flight attendant. Dugas, 'who contracted AIDS before 1980 and died in 1984, was, publicly identified as "Patient Zero" only quite recently. Tissue samples from Robert R. may eventually reveal what caused the virus to spread.

Two researchers, microbiologist Memory Elwin-Lewis of Wash­ington University in St. Louis and Marlys Witte, a professor of surgery at the University of Arizona in Tucson, told of a black teenager who showed up at St. Louis Cily Hospital in 1968 with chronic genital swelling. The youngster, then 15, admitted that he was sexually active; laboratory tests disclosed that he had a severe case of chlamydia, a common but curable venereal disease. Doctors prescribed several antibiotics and put him on a low-salt diet. Nothing worked. His muscles wasted away, and his lungs filled with fluid. Robert R. died on May 15, 1969. An autopsy revealed the distinctive purplish lesions of AIDS-related Kaposi's sarcoma.

Hoping at the time that medical advances might someday solve the mystery of his affliction, Elwin-Lewis and Witte, then both at Washington University, froze samples of Robert R.'s blood, brain and other organs. In June 1987, four years after the AIDS virus was first isolated, Witte sent some of the frozen samples to Tulane University, where they were definitely analyzed by Virologist Robert Garry. (There's no question that the tissue was positive for AIDS", Garry states. In fact, Robert R.'s blood reacted to all nine markers used in the highly sensitive Western blot test for AIDS antibodies. Why didn't the researchers have the samples tested earlier? "We waited until the chance of documenting the infection was more likely". Witte explains.

Robert R.'s case is even more intriguing because he never visited New York City, San Francisco and Los Angeles, the current AIDS epicenters. In fact, he told his doctors, he never left the Midwest. That is not surprising, says Dr James Curran, director of the AIDS program at the Center for Disease Control. "It's just not logical that AIDS entered the country only once", he says. I think that there were several entry points but that most of them occurred in the late 1970s".

Other presumptive cases are emerging from the past. In New York City in 1959, for example, a 49-year-old Haitian-born shipping clerk fell victim to what today would be a telltale disorder:

"Pneumocystis carinii" pneumonia. "It was so unusual at the time", recalls Dr. Gordon Hennigar, who performed the postmortem




and is now chairman of pathology at the Medical University of South Carolina. "AIDS is such a strong possibility that I've often thought about getting the samples and testing them".

Indeed, the history of AIDS in the U.S. may have a much longer prologue than was once suspected. "What we're saying is that AIDS has been around for a long time but just wasn't recognized", Elwin-Lewis explains. It is possible, Tulane's Garry speculated, that the AIDS virus mutated and became more lethal in the 1970s. To test that hypothesis, he plans to spend much of the next year or so attempting to reconstruct viral genes from Robert R.'s tissue. "We know that the virus was not epidemic in 1969, so we might be able to identify the changes between then and now that enabled it to spread, Garry says. If scientists can figure out how the AIDS virus might have changed, the puzzling case from the past might shed light on the future of the epidemic.

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Date: 2016-04-22; view: 315


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