Latency of Herpes Simiae (B virus) in rabbits.

When small doses of herpes simplex virus (HSV) were given to rabbits a significant degree of protection was afforded against later infection with herpes simiae (B virus). Only 12/47 rabbits died within 3 weeks of receiving B virus dosages that would normally have proved lethal. B virus became latent in survivors and was recovered from brain and spinal cord suspensions from rabbits which died within 6 months and from dorsal root ganglia of rabbits which had survived for more than 2 years without overt signs of infection. A minority of the survivors tested also yielded HSV. Rabbits with latent B virus in the ganglia showed little or no detectable neutralizing antibody to B virus. The possibility is discussed that human populations having a high frequency occurrence of HSV antibody may include carriers of latent B virus.