THE JEREMIAH METZGER LECTURE VARICELLA ZOSTER VIRUS: FROM OUTSIDE TO INSIDE.

Varicella zoster virus (VZV) gives rise to two diseases, a primary infection, varicella, and a secondary infection, zoster. Morbidity and mortality from VZV in the United States has decreased by 80% to 90% due to the effective use of attenuated live viral vaccines. Because latent VZV continues to reactivate, however, serious VZV-induced disease persists. Newly developed molecular analyses have revealed that zoster is more common than previously realized; moreover, the establishment of VZV latency in neurons, such as those of the enteric nervous system, which do not project to the skin, leads to unexpected, serious, and clandestine manifestations of disease, including perforating gastrointestinal ulcers and intestinal pseudo-obstruction. The development of the first animal model of zoster, in guinea pigs, now enables the pathophysiology of latency and reactivation to be analyzed.