Feral Cat Veterinary Resource Center
Rabies Control in the U.S.
Rabies outbreaks were once common in the U.S. As recently as 1946, the U.S. reported 33 human cases of rabies and more than 8,000 cases among dogs. In 1947, a national rabies program was established to tackle the problem. This initial rabies eradication effort focused mostly on dogs, which were originally the most common source of rabies exposure.
In addition to vaccination, early rabies control efforts often involved capturing and killing dogs that were found roaming, says Julie Levy, DVM, PhD, at the University of Florida in Gainesville. But rounding up and killing strays cannot eliminate rabies, because it’s nearly impossible to entirely extinguish a stray population. Removing animals tends to trigger what is known as the vacuum effect, and merely opens up territory for new, possibly rabid, strays to move in and continue breeding. Learn more about the vacuum effect.
Instead, it’s vaccination programs that have proven most potent at controlling rabies. Now that rabies vaccination has become common for dogs and other domestic animals, rabies has nearly vanished from these populations. According to the Centers for Disease Control and Prevention, “As canine rabies was controlled and ultimately eliminated, the epidemiology of rabies in the United States shifted to primary circulation in wildlife species.”1 Today, wildlife remains the most common source of rabies viruses, making up more than 90% of reported cases. Communities concerned about rabies should focus on effective wildlife programs, such as the Oral Rabies Vaccine (ORV). In 2008, ORV programs in Texas led to the eradication of the domestic dog-coyote variant of the rabies virus in the U.S.
Programs that combined vaccinations with the killing of stray dogs are sometimes offered as a model for controlling rabies in feral cat colonies, but this approach fails to recognize that dogs carry their own dog-adapted strain of canine rabies that allowed the virus to thrive in stray populations. Cats do not have their own strain of rabies, and Levy says that cats are merely incidental victims that develop rabies from wildlife. Feral cat colonies rarely harbor rabies, and TNR protects them from contracting the disease.
1 Blanton, Jesse D., Dustyn Palmer, Jessie Dyer and Charles E. Rupprecht. Rabies Surveillance in the United States during 2010. Journal of the American Veterinary Medical Association 239 (2011): 773-783.