Rabies Transmission
The virus of rabies is found in the saliva of the rabid dog. The presence, quantity, and virulence of the 
virus in the saliva may vary considerably in different animals and even in the same animal during the course of the disease. After death the viruses found in the brain and spinal cord. Evidence has been presented to show that the virus of rabies may be present in the animal someday before clinical symptoms are apparent. It has been demonstrated that the bite of a dog may be infectious at least 3 days before the dog manifests symptoms of rabies, and in one case in the Pasteur Institute at Athens, Greece, infection was found to be presenting the saliva 8 days before the dog showed signs of the disease. Exact information is not available on the regularity with which the virus appears in the saliva before animals show evidence of the disease, nor is there exact information on the persistence of the virus in the saliva of animals showing clinical symptoms.
For a dog to transmit rabies through a bite, it must itself be affected with the disease. Bites of dogs not affected with rabies cannot result in the transmission of rabies. The bite of a normal dog can be disregarded from the standpoint of the possibility of its producing rabies and need only be treated as any other injury would be.