Early street rabies virus infection in striated muscle and later progression to the central nervous system

Twelve isolates of street rabies virus were inoculated intramuscularly into young hamsters and the course of infection was followed by frozen section immunofluorescence. Animals infected with 10 of the 12 viruses had antigen in striated muscle at day 3, but involvement of other tissues was absent or extremely sparse. Muscle infection was still most pronounced at day 6, but neuromuscular spindle, nerve, and brain infections were also detected in a majority of animals. Progression of infection was continuous, with striking terminal accumulations of antigen. The early myotropism of rabies virus may yield the virus which invades the peripheral nervous system, and may represent a phase of infection vulnerable to postexposure intervention.