Monkey Virus Could Lead To AIDS Vaccine
BRUSSELS, Belgium (AP) _ A researcher on Saturday said he had discovered a close relative of a monkey AIDS virus that can infect humans without making them sick, suggesting that it might make an effective vaccine to prevent AIDS.
The new virus was found in individuals in Senegal, on the western edge of Africa just south of the Sahara desert, said Max Essex of the Harvard School of Public Health in Boston.
He spoke at an international symposium on African AIDS that drew 700 researchers from 51 countries, including more than a dozen countries in Africa.
About 50 of the African participants met separately Saturday to draft a politically charged statement saying there is no conclusive evidence that AIDS originated in Africa.
Essex said that his discovery of the monkey AIDS virus in African green monkeys does not necessarily mean that AIDS arose in Africa.
He believes the monkey virus passed to a human through some rare event, such as a monkey scratching or biting a hunter, thus passing the virus into the hunter’s bloodstream.
Once that happened, the virus mutated slightly, Essex believes, to adopt the form it now has in humans. But the virulent AIDS virus - the one that causes the disease - could have arisen anywhere, Essex said.
What is important with regard to a vaccine, though, is that neither the humans who carry the newly discovered virus nor the African green monkeys who harbor its close relative show signs of illness.
″We have to consider that infection with the African green monkey virus might protect against later infection with the more virulent form (of the AIDS virus),″ Essex said.
The first vaccine ever made, the smallpox vaccine, was made with just such a virus, Essex noted. Cowpox virus - which did not cause disease in humans - was found to confer immunity against smallpox, which it closely resembled.
Essex is referring to the virus as AIDS virus variant AGM (for African green monkeys). The monkey virus is called simian T-cell lymphotropic virus type III, or STLV-III.
That virus, too, was discovered by Essex and his collaborators, according to a report in the Nov. 22 issue of Science magazine.
The African scientists who met Saturday concluded, in a statement given to the press, that ″during this symposium, papers presented did not show any conclusive evidence that AIDS originated in Africa.″
″It is a global problem and not an African problem alone,″ the scientists wrote.
They called for the development of simpler, less expensive tests for the AIDS virus, and asked African governments to help collect data on the frequency of the disease. The governments of central Africa have so far generally refused to tell the World Health Organization how many cases of AIDS and related diseases have been found within their borders.
Dr. Herbert Nsanze, a Ugandan now living in the Fiji Islands where he works for the World Health Organization, disputed the widely repeated observation that AIDS has reached epidemic proportions in Africa.
″The total numbers do not constitute an epidemic,″ Nsanze said in an interview.
Dr. David Serwadda, a Ugandan who helped identify slim disease, a variant form of AIDS marked by extreme weight loss, said Africa needs help and isn’t getting it.
″When the Western researchers came to Africa, they were interested in pinning it (AIDS) on Africa,″ Serwadda said. ″They didn’t come to help.″
Serwadda, who is living in England but is affiliated with Makerere Medical School in Kampala, Uganda, also saw racial prejudice in some observations being made about African AIDS.
″Everybody thinks that every other African is walking around with AIDS,″ he said. ″I can foresee Africans being quarantined.″