Responses of mice to inoculation with low doses of a bat rabies virus variant.

Rabies is generally considered a fatal disease, yet neutralizing antibodies to rabies virus (RV) have frequently been found in sera from healthy, insectivorous bats, and mark-recapture studies have demonstrated bats that are still alive years after the first detection of anti-RV antibodies. To explore this phenomenon, we exposed mice to a big brown bat variant of RV, using three routes of inoculation, two doses of virus and two frequencies of exposure. We found the highest rate of seroconversion without mortality in mice that received repeated intramuscular inoculation of the higher dose of virus, and mice inoculated intranasally experienced the highest mortality.