The virus is transmitted from an animal to a person, or from one animal to another, via infected saliva, most often by biting but also by the contact of torn skin with infected saliva. The virus travels from the bite or contact location to the spinal cord and brain. In humans the incubation period ranges from 10 days to a year or more.
Symptoms are fever, uncontrollable excitement, and pronounced spasms of the throat muscles.
Following a bite from a rabid or possibly rabid animal, preventive treatment involves administration of immune globulin for passive immunization followed by vaccinations over several weeks for active immunization. The only treatment after symptoms appear is rest and sedation. Dogs have been immunized from the time Louis Pasteur demonstrated a successful vaccine in 1885. Since then, human rabies has become rare in the United States and other industrialized countries due to comprehensive vaccination programs for domestic animals. Mass vaccination of susceptible animals in the wild has been used in an effort to stem an increase of rabies cases in the United States and Canada that began in the late 1980s.