DÉTENTE. “New evidence in animals indicates that chronic virus infection can fundamentally alter innate immunity to nonviral pathogens. IFN-γ expression during herpesvirus latency can symbiotically protect the host from infection by the bacteria Listeria monocytogenes and Yersinia pestis, the causative agent of plague. Thus, the détente developed between herpesviruses and their hosts over tens of millions of years of coevolution may offer benefits to the host.”
http://www.sciencedirect.com/science/article/pii/S0092867409007831