Due to the continuing implementation of mandatory dog rabies vaccinations since the 1950's, dogs spreading rabies is less of a public health concern in the United States than it was previously. Public education and licensing requirements have drastically decreased rabies cases in domestic animals; however, rabies cases in wild animals continue to occur.

Rabies virus is spread through the saliva of infected animals in the terminal stages of the disease. The virus is most often transferred by a bite wound but it can also infect mucous membranes (such as the eye or nose). To be protected against rabies a person or animal must be immunized before being bitten or receive immediate post-exposure treatment administered by a medical professional. If untreated, rabies infection is essentially 100% fatal.