Contentious finger-pointing over who is to blame for the worldwide spread of the AIDS virus--which has pitted Africans against Europeans and Asians against Westerners--threatens to disrupt the international cooperation necessary to fight the AIDS epidemic.
The suggested villains include not only the CIA and the Soviet's KGB, but also French paratroopers, Cuban military advisers in Angola, Pakistani terrorists, and even the World Health Organization's smallpox eradication campaign.
Leading scientists from many countries, including the United States, France and the Soviet Union, have refuted each of these rumors, only to see them replaced by other bizarre notions.
"People have written to me to say that AIDS came from Mars or from outer space on meteorites," said Dr. Jonathan Mann, the director of the World Health Organization's special program on AIDS. "Others have said it was washed to Earth on rain or came from lizards."
Most researchers state unequivocally that the AIDS virus occurred naturally and spread throughout the world in a silent epidemic in the 1970s before the first AIDS cases were reported.
But scientists have been unable to pinpoint the geographic origins of the AIDS virus family or to solve the riddle of when and how the first humans became infected.
This uncertainty persists despite intensive research into the origins of AIDS, which has focused on Africa.
One reason that scientists looked to Africa is that some viruses similar to the AIDS virus are harbored by the African green monkey, and these viruses have not been found in monkeys or in other non-human primates elsewhere. Also, several new AIDS-like viruses have been isolated from humans in West Africa.
The AIDS virus seem to have "proliferated" there and "expanded in terms of the number of people infected" before large numbers of humans became infected in other parts of the world, according to Patricia Fultz, chief of AIDS animal model studies at the U.S. Centers for Disease Control.
Although no definitive answers for an origin of AIDS have emerged, that has not stopped people from searching for scapegoats.
Some of the more fantastic claims about the origins of AIDS were outlined in the weekly Costa Rican newspaper Semanario Universidad in April.
A full-page story suggested that the AIDS virus had been designed in a biological warfare center in Maryland, then transmitted in Africa and Haiti as a method designed by the military-industrial complex for ridding the world of homosexuals or "neutralizing" blacks. The story, written by three staffers, also speculated that the AIDS virus was produced by the CIA because of a belief that gays could become a dangerous voting bloc.
A totally different theory was set forth in a front page article in The Times of London on May 11.
The article asserted that the World Health Organization's mass smallpox immunization campaign, which led to the global eradication of the deadly disease in 1977, may have unwittingly transformed the disease from a minor Third World illness into a worldwide epidemic through the reuse of vaccination needles. The article cited as its prime authority "an adviser to WHO" who was never identified by name.
In response, Mann wrote in a letter published by the British newspaper: "The only result we know of from the smallpox eradication program was the eradication of smallpox itself."
He said the Times' theory was unsupported by scientific data. For example, Mann noted, the AIDS virus is virtually absent from Asia, where hundreds of millions of smallpox vaccinations were given. There is also a high prevalence of the AIDS virus in the United States, where smallpox was eradicated many years ago.
The persistence of rumors also has alarmed the World Health Organization's governing body, the World Health Assembly, which is composed of representatives of the organization's 166 member nations.
When the World Health Assembly on May 15 unanimously adopted a resolution establishing the organization's global AIDS control strategy, the second paragraph stated that AIDS was "caused by one or more naturally occurring retroviruses of undetermined geographical origin."
"The phrasing was not accidental," Mann said. "It has been interpreted by many people as directly addressing the issue (that the AIDS virus was created in a laboratory)."