How scientists investigate sleeping viruses using the herpes simplex virus (HSV) .

How scientists investigate sleeping viruses using the herpes simplex virus (HSV).Most virus infections are 'latent' (sleeping) within the nervous system. Princeton scientists are investigating how they go to sleep -- and how to prevent it. Four in five adults are infected with herpes simplex virus, say researchers, but most don't show symptoms like cold sores because the virus infection is 'latent' -- sleeping -- within the nervous system. While many virus researchers are interested in understanding what causes these sleeping viruses to wake up, or reactivate, scientists are now trying to understand what prevents the infection from going to sleep in the first place.