In the United States, the wildlife species most involved in rabies transmission are skunks, raccoons, foxes, and insectivorous bats.
Raccoons currently rank second to skunks as the major reservoir.
Rabid foxes are a major source of the disease in Canada and many European countries. Although live-attenuated rabies virus vaccines are effective in immunizing foxes against rabies, they are not effective for immunizing skunks and raccoons. An oral rabies recombinant vaccine, based on a putative indigenous raccoon poxvirus, has been developed using raccoon poxvirus as the expression vector. The vaccine confers protection against rabies to a number of wild and domestic animals.