Naturally acquired simian varicella virus infection in African green monkeys

Simian varicella virus (SW) infection of primates shares clinical, pathological, immunological, and virological features with varicella-zoster virus infection of humans. Natural varicella infection was simulated by exposing four SW-seronegative monkeys to monkeys inoculated intratracheally with SW, in which viral DNA and RNA persist in multiple tissues for more than 1 year (T. M. White, R: Mahalingam, V. Traina-Dorge, and D. H. Gilden, J. Neurovirol. 8:191-205, 2002). The four naturally exposed monkeys developed mild varicella 10 to 14 days later, and skin scrapings taken at the time of the rash contained SW DNA. Analysis of multiple ganglia, liver, and lung tissues from the four naturally exposed monkeys sacrificed 6 to 8 weeks after resolution of the rash revealed SW DNA in ganglia at multiple levels of the neuraxis but not in the lung or liver tissue of any of the four monkeys. This animal model provides an experimental system to gain information about varicella latency with direct relevance to the human disease.