Science / Medicine : An ‘Off’ Switch for Herpes

Scientists believe that they have found a genetic “off” switch that keeps the herpes virus dormant in the body, a discovery that could mean new strategies for controlling a variety of viruses.

They found the genetic trigger in herpes simplex virus type 1, the virus that causes cold sores. They believe the same mechanism controls its cousin, herpes simplex virus type 2, which causes genital herpes.

The newly described gene is one of about 80 that play various roles in the herpes virus’s life cycle. However, it is the only one that stays active when people are infected with the virus but do not have cold sores. The researchers believe that it is a kind of master switch that keeps all the other viral genes from kicking into life.

Dr. Stephen E. Straus, a co-author of the study, said the finding suggests that the virus has to do something to keep dormant. “It’s not just sitting there doing nothing, as had been previously believed,” he said.