A team of international scientists have produced new information that questions the evidence against the six medics on trial in Libya accused of deliberately infecting Libyan children with HIV.
The five Bulgarian nurses and a Palestinian doctor, who have now been incarcerated in a Libyan jail for almost eight years, were accused of deliberately infecting 426 Libyan children with HIV at a hospital in Benghazi in 1998.
In a re-trial in Tripoli of the six health workers which ended last month, the prosecution demanded the death penalty and stood by the evidence of five Libyan HIV/AIDS experts who found in their report in 2003 that the infections resulted from an intentional act.
The court is expected to deliver a verdict on December 19th, but the international scientists who reconstructed the history of the virus from samples from 44 of the children say the subtype of HIV began infecting patients at the Al-Fateh Hospital in Benghazi years before the foreign medical team arrived.
The researchers worked on blood samples collected by a network of European clinical research centres that are involved in treating the infected children.
Dr. Tulio de Oliveira, a molecular virologist at Oxford University in England, has said the chain of infection started a few years before the arrival of the foreign staff accused of causing it deliberately.
The virologists say all children examined were infected at the same time with a virus typical for Western Africa; a number of immigrants from Western Africa live in Libya.
The scientists have published their findings online in the journal Nature, and say they carried out an extensive analysis using 20 different models, which examined the genetic code of HIV and Hepatitis C viruses from the children in order to determine when the outbreaks started.
De Oliveira says all of them gave a date for the start of the epidemic around the mid-1990s.
The results have been supported by a team of 10 specialists from around the world who reviewed the research; they say the results are "extremely solid."
The six medics have repeatedly protested their innocence and say initial confessions had been extracted under torture.
They arrived in Libya in March 1998 and have been in detention since 1999.
They were sentenced to death by firing squad after being convicted in a trial in 2004, but the international outcry which ensued resulted in the verdict being quashed last year by the supreme court and a re-trial ordered.
De Oliveira and his colleagues in Oxford collaborated with scientists from several European universities to conduct an independent scientific assessment of the data.
Their findings are expected to be presented to the Libyan authorities.