Viruses under the microscope

Human herpesviruses such as HHV-6 can remain dormant in cells for many years without being noticed. When reactivated, they can cause serious clinical conditions. Researchers from Würzburg have now found a way of differentiating between active and inactive viruses. Human herpesvirus 6 (HHV-6) infects almost all of the human population, but only very few will show any symptoms during their lifetime: HHV-6 is one of the most widespread viruses among the population. Between 95 and 100 percent of healthy adults have antibodies to the virus which means that they have been infected at some point in the past. The virus hides in the genomic DNA There are two types of the virus: HHV-6A and HHV-6B. HHV-6B primarily infects in infancy as sixth disease, whereas HHV-6A infections usually remain asymptomatic. After primary infection, the virus establishes lifelong latency by integrating with the cellular DNA. The infection is generally harmless. Under certain circumstances, however, the virus...