Did Doctors Jumpstart the HIV Pandemic? 24/9/10

Dirty needles "played a substantial role that was probably as important as prostitution,"

Reuters

"Everybody now is getting infected from having sex," said Strickland, who wrote an editorial about the new findings, published in the journal Clinical Infectious Diseases.

"But that is not very good transmission. You can have heterosexual sex ten or fifteen times without getting infected. But if you get injected with a contaminated needle, the risk is much higher."

Pepin's other study shows that in Cameroon, a neighboring state that also used to be under French rule, massive outbreaks of hepatitis C in the first half of the 19th century were related to malaria treatment with the drug quinine.

More than half the hundreds of graying heads he rounded up had traces of an earlier hepatitis C infection in their blood.

"The most important mode of infection was the intravenous treatment of malaria," said Pepin. "If we put all of this together, it shows that there was a lot of transmission of different viruses through different interventions for tropical diseases."

"Probably HIV was transmitted as well," he argues.

But nobody is left to bear witness of what really happened, and not all scientists believe Pepin's explanation.

"It is a wonderful study on the hepatitis C virus," said Michael Worobey, a biologist at the University of Arizona in Tucson who studies the origins of HIV. "I'm not so convinced it should have been sold on the HIV/SIV angle."

His version of what happened follows the traditional line of argument among scientists: as colonial powers began building cities and railroads, they transformed former woodlands into densely populated towns rife with prostitution -- perfect hotbeds for blood-borne diseases.

Eventually an infected villager made his way to the city, setting off the HIV epidemic like a spark falling on a dry savanna.

"I think a train is a much better way to get a virus to a city than a needle," Worobey told Reuters Health.

He said the idea that doctors kicked off the HIV pandemic has been around for years. And while the new experiments are probably the first to test it, he added, they don't settle the question.

To Pepin, the two explanations aren't mutually exclusive. Dirty needles "played a substantial role that was probably as important as prostitution," he said.

Although single-use needles are now commonplace in most of the world, and unprotected sex is the major reason people get HIV, Pepin said some wisdom might still be gleaned from what he found.

"Hopefully it will make doctors a bit more prudent about novel medical interventions," he said.