A harmless virus common in the general population delays the development of AIDS, according to a study released Wednesday that could help researchers find new treatments for the epidemic.
The benign virus can persist in the body for years and appears to interfere with HIV, the AIDS virus which affects 40 million people worldwide and has killed another 30 million.
Both HIV and the benign virus, known as GBV-C, infect the same types of cells.
Jack Stapleton of the University of Iowa and his colleagues found that HIV-infected men who were no longer infected with GBV-C after five to six years died nearly three times faster than men who continued to show signs of the infection.
And once the GBV-C virus was gone, the AIDS virus seemed to attack with renewed vigor.
A 'good virus' to have?
“So not only was having a persistent infection better survival-wise than not having an infection, but the subset of men who lost their virus did the worst. It’s very unusual that there would be a good virus,” Stapleton told Reuters.
The 10-year survival rate was 75 percent for men who showed evidence of the virus at both the one- and five-year marks, 39 percent among people who had never had a GBV-C infection and 16 percent for those whose bodies had cleared the GBV-C virus.
GBV-C does not appear to block people from getting HIV, so it would not be a vaccine. But in a commentary in this week’s New England Journal of Medicine, where the study appears, Roger Pomerantz and Giuseppe Nunnari of Thomas Jefferson University in Philadelphia said it could help doctors find new treatments.
Meanwhile, Stapleton and his colleagues are planning experiments to treat HIV cases with blood from people who are carrying the GBV-C virus. Volunteers for that study have already been lined up.
Research into GBV-C has been controversial because some studies have suggested it does not slow the progression from HIV infection to AIDS.
The Stapleton team found the harmless virus, once thought to be a cause of the liver disease hepatitis, does not improve survival during the first 18 months after an HIV infection takes hold.
Only in later months does the benefit of a GBV-C infection become significant.
The benign virus is found in nearly 2 percent of seemingly healthy blood donors, according to a study done in Iowa. In all, 13 percent of the donors in that study had evidence of a past or present GBV-C infection.
Stapleton said the GBV-C virus probably spreads like the AIDS virus, through blood products and sexual contact. It is more common after puberty.
