A harmless virus that seems to infect millions of people without causing symptoms may help slow the deadly progress of the AIDS virus, researchers said.
The virus, called GBV-C, may block one of the cellular doorways used by the AIDS virus to infect cells, researchers told a meeting of HIV experts. More studies may lead to new ways to treat AIDS, which infects 36 million people worldwide.
The good news is that many HIV patients in the United States seem to be infected with the GBV-C virus, the researchers told the 10th annual Conference on Retroviruses and Opportunistic Infections being held in Boston, Massachusetts.
The findings may help explain why some people survive for decades without serious complications from the virus, said Dr Carolyn Williams of the National Institute of Allergy and Infectious Diseases, who helped lead one of the studies.
Such patients eventually succumb to the virus but the process takes much longer than for the average patient.
Researchers discovered GBV-C in 1995. They also called it hepatitis G but that name has been dropped because, unlike hepatitis viruses, this one does not seem to damage the liver. Like the AIDS virus, GBV infects immune-system cells called lymphocytes.
In September 2001, a team at the University of Iowa reported they had found the virus in the blood of HIV patients, and said these patients seemed to resist the ravages of AIDS for longer than normal.
Last week at the retrovirus meeting, the largest annual gathering of AIDS medical researchers, the Iowa team and another group headed by the National Institute of Allergy and Infectious Diseases confirmed the effect.
"We found that men who were persistently positive for GBV-C were 2.5 times more likely to survive," the institute's Williams told reporters.
They looked at blood taken from 271 HIV patients when they first visited a doctor. Eleven years later, 75 per cent of the men who had persistent GBV-C infections were still alive, compared to 39 per cent of those who had never been infected with GBV.
The word "persistent" is important, because there were 12 men whose bodies had cleared the GB virus and, of them, only 16 per cent were alive 11 years later.
(Agencies February 19, 2003)
