The round trip model for severe herpes zoster caused by live attenuated varicella vaccine virus.
Varicella vaccine is a live attenuated varicella‐zoster virus. Varicella vaccine can enter latency and later reactivate as herpes zoster. Pseudorabies virus is another herpesvirus closely related to varicella‐zoster virus. The round trip model for pseudorabies virus explains pathogenesis of herpes zoster from vaccine virus.