The international medical community is raising a chorus of protest against a Libyan trial of six Bulgarian and Palestinian health workers. The six are accused of deliberately infecting hundreds of Libyan children with the AIDS virus. The defendants face the death penalty when their trial ends October 31, but health experts say the evidence against them is worthless.

Relatives of Bulgarian nurses jailed in Libya hold banners that call on Libyan leader Moammar Gadhafi to release them

American and European researchers are protesting the trial of five Bulgarian nurses and Palestinian doctor on charges of purposely injecting 426 Libyan children with HIV in 1998 at a Benghazi hospital. In August, the prosecution asked for the death penalty.

"This case is a very troubling case," said Janine Jagger.

University of Virginia epidemiologist Janine Jagger heads the school's International Healthcare Worker Safety Center.

"The kind of evidence that the prosecution is basing its case on is that, they claim, these infections cannot be explained any other way," she said. "But they have no evidence to specifically link these workers to these specific infections."

Jagger says that, by contrast, there is plenty of evidence to show that the six foreigners are innocent, but the Libyan court has rejected it. It has also denied the defendants' requests to present testimony by international scientists who might vindicate them.

The evidence in their support comes from a team led by the co-discoverer of the AIDS virus, Luc Montagnier of France. It is based on analysis of blood samples taken from many of the HIV-infected Libyan children when they were treated in European hospitals.

"Through his analysis, it was determined that some of these cases had been infected before the arrival of the workers and there is no way to link those cases by the viral analysis that was done," noted Janine Jagger.

Montagnier's report also shows that many of the Libyan children were also infected with hepatitis B and C, suggesting that unsafe practices were common in the Libyan hospital.

The other co-discoverer of the AIDS virus, Robert Gallo of the University of Maryland, has joined 43 U.S. and European scientists in a letter published in the journal Science decrying the Libyan trial, the alleged torture of the six defendants, and forced confessions during their seven years of imprisonment.

"When one saw all the evidence collected, it was clear that these people are innocent," said Robert Gallo. "There is close to absolute proof and certainly no suggestion that they did anything except these so-called confessions."

In addition to the confessions, the Libyan court has accepted a report by five Libyan physicians implicating the foreign health workers in the HIV cases. According to an English translation of the report obtained by the journal Nature, they argue that Libyan hospital sanitation was not a problem. They also say that the HIV outbreak involved so many children and was of an unusual strain that it must have been malicious.

But Jagger says the report is worthless.

"The evidence in terms of the prosecution's case is the most vague evidence that I have ever seen," she said. "I mean, this kind of evidence wouldn't even be admissible in a court in the United States."

Jagger says she believes Libya's government brought the charges to cover up medical deficiencies in the Benghazi hospital.

President Bush has said the defendants should be freed.

This is not the first trial the Bulgarian and Palestinian medics have faced. They were convicted in 2004 and sentenced to death by firing squad. But Libya's Supreme Court overturned the sentences, saying there were some problems with how Libyan authorities handled the case.

Robert Gallo says he and his colleagues felt compelled to speak out now because the current trial is coming to an end. He urges concerted international pressure against Libya if it results in another conviction.

"I would hope there would be an outcry in the United Nations," he said. "I would hope there would be very strong international governmental anger by the political leaders."

Gallo and his colleagues say Libya's action sends a chilling message to health care workers giving lifesaving HIV care in difficult circumstances.