Antigenic relationships among several simian varicella-like viruses and varicella-zoster virus

Cross-neutralization and complement fixation tests demonstrated the immunological identity of the Delta herpesvirus, the 592S virus, the Liverpool vervet monkey virus, the herpesvirus of patas monkeys, and the Medical Lake macaque virus. These viruses were isolated from diverse outbreaks of varicella-like disease in simians and from various simian species. All of the simian viruses were shown to be related to human varicella-zoster (V-Z) virus, as evidenced by the fact that immunization of monkeys with each of the simian viruses elicited the production of both neutralizing and complement-fixing antibodies to V-Z virus. However, cross-complement fixation tests indicated that the simian viruses are not so closely related to V-Z virus as they are to one another. Varicella or zoster infections in humans produced neutralizing and complement-fixing antibody responses to each of the simian viruses; the responses were more marked in zoster infections than in varicella infections but, in most patients, antibody levels produced to the simian viruses were much lower than those to the homologous V-Z virus.