A non-lethal test of the resistance of inbred mice to herpes simplex virus type 1.

Inbred strains of mice varying in susceptibility to intraperitoneal (i.p.) inoculation of HSV-1 were tested by inoculating 10(5) p.f.u. of the SC 16 strain into the ear pinna. Increase in ear thickness was less in resistant than in susceptible strains. In the resistant C57BL/6 strain, local replication of virus, spread to cervical ganglia and development of latent infections of the ganglia were all less than in susceptible DBA/2 mice; there was also less cellular infiltration of the inoculation site. Like resistance to i.p. inoculation, resistance to ear inoculation appears to be inherited as a dominant characteristic. The test provides a non-lethal method of distinguishing between resistance and susceptibility of inbred strains of mice to HSV-1 and may also be useful in defining resistance factors.