Wild animals get rabies the same way any mammal does: through the saliva of an already-infected animal, almost always delivered by a bite. The virus lives in the salivary glands of a rabid animal, and when that animal bites another, saliva carrying the virus enters the wound and begins its slow journey toward the brain. In the United States, wild animals account for more than 90% of all reported rabies cases, with the virus circulating continuously among a handful of key species.
How the Virus Spreads Between Animals
A bite is the primary route. When a rabid animal’s teeth break the skin of another animal, virus-laden saliva is deposited directly into muscle tissue. From there, the virus latches onto nearby nerve endings and begins traveling inward along nerve fibers, using the cell’s own internal transport system (the same molecular machinery that neurons use to shuttle nutrients and signals) to move toward the spinal cord and brain. This journey is slow and silent. The infected animal shows no symptoms during this time.
Once the virus reaches the brain, it replicates rapidly and then reverses course, spreading back outward along nerves into organs throughout the body, including the salivary glands. At this point the animal becomes infectious, its saliva now loaded with virus, and the cycle is ready to repeat with the next bite.
Non-bite transmission is possible but extremely rare. Scratches that break the skin, saliva landing on mucous membranes like the eyes or mouth, and direct contact with an open wound can all theoretically transfer the virus. Inhaling virus-containing aerosols, such as in densely populated bat caves, has been documented in a tiny number of cases. For practical purposes, though, bites are what keep rabies moving through wildlife populations.
Which Wild Animals Carry Rabies
Rabies doesn’t circulate evenly across all wildlife. It persists in specific “reservoir” species, populations large and connected enough to sustain the virus long-term. In the United States, five terrestrial species serve as reservoirs: raccoons, skunks, foxes (both gray and arctic), and the small Indian mongoose in Puerto Rico. Bats round out the list and are unique because bat rabies exists in every state except Hawaii, unconstrained by the geographic barriers that limit terrestrial reservoirs.
The CDC breaks down reported wildlife rabies cases this way: bats make up about 35%, raccoons 29%, skunks 17%, and foxes 8%. Each reservoir tends to dominate a particular region. Raccoons carry the virus primarily along the eastern seaboard, from Florida to Canada and as far west as the Appalachian range. Within those areas, roughly 10% of raccoons involved in human or pet exposures test positive. Skunks are the main reservoir across the Midwest and West, and they carry the highest bite-for-bite risk: more than 20% of skunks that bite or scratch a person or pet turn out to be rabid. Foxes pose a similar risk, concentrated in the Southwest and Alaska, with outbreaks reported in Arizona, California, and Alaska since 2023.
Some parts of the country, like Washington and Oregon, appear to be free of terrestrial rabies reservoirs entirely, though bat rabies is still present.
Reservoir Species vs. Spillover Species
Any mammal can catch rabies, but there’s an important distinction between reservoir species and “spillover” species. Reservoirs maintain the virus within their own populations through ongoing animal-to-animal transmission. Spillover happens when a rabid reservoir animal bites a different species, like a rabid raccoon biting a groundhog. The groundhog can get sick and die, but groundhogs don’t sustain the virus among themselves. If the reservoir disappeared, so would the spillover cases.
This is why certain animals you might worry about are actually low-risk. Small rodents like squirrels, chipmunks, and rabbits are rarely found with rabies, likely because a bite from a larger rabid predator would kill them before the virus could establish. Opossums also test positive very infrequently.
How Long Before an Infected Animal Gets Sick
The incubation period, the gap between the bite and the first symptoms, varies widely depending on the species and where on the body the bite landed. Bites closer to the brain (the face or neck) produce shorter incubation times because the virus has less nerve fiber to travel.
Across species, the average incubation period in experimental studies is about 22 days, with a median of 17 days. But the range is enormous. Foxes and other canids average around 19 days, with some cases appearing in as few as 3 days. Raccoons average about 22 days. Skunks have the longest and most variable incubation, averaging 41 days, with some cases not appearing for over 300 days. About 6% of skunks in experimental studies had incubation periods exceeding 100 days. This long, hidden phase is part of what makes rabies so persistent in wildlife: an animal can be infected and spreading the virus in its saliva before anyone, human or animal, has reason to suspect it.
Behavioral Signs of Rabies in Wildlife
Because rabies attacks the brain, infected animals often behave in ways that seem “off.” The classic signs include nocturnal animals like skunks and bats appearing active during the day, wild animals approaching people without fear, stumbling or walking in circles, and unprovoked aggression. A fox walking calmly toward you in your backyard, or a raccoon sitting still in the open at noon, is exhibiting the kind of behavior that should raise a red flag.
Not all rabid animals look aggressive. Some become unusually quiet and docile, a form sometimes called “dumb” rabies as opposed to the “furious” form. Either way, the virus alters normal behavior in ways that, conveniently for the virus, increase the chance of a bite. An aggressive animal picks more fights. A fearless animal wanders into closer contact with other species. Both patterns help the virus find its next host.
Rabies in Wildlife Outside the U.S.
Globally, the reservoir picture looks different. In much of Africa and Asia, domestic dogs remain the primary reservoir, responsible for the vast majority of the estimated 59,000 human rabies deaths each year. In Europe, the red fox was the dominant wildlife reservoir for decades, with the virus spreading westward from Russia and Poland starting in the 1940s and reaching southern France by the early 1990s. Raccoon dogs, originally introduced from eastern Asia by the fur industry, now maintain a separate rabies cycle across the Baltic states, eastern Europe, and Finland. In Latin America, where dog rabies has been largely controlled, vampire bats (blood-feeding bats) have become the main source of human rabies cases.
How Wildlife Vaccination Programs Work
Because you can’t round up wild raccoons and skunks for shots, wildlife agencies use oral rabies vaccine baits. These are small packets containing a liquid vaccine hidden inside a flavored coating designed to attract the target species. They’re distributed by aircraft across large areas, typically at a density of about 20 baits per square kilometer, and also placed by hand in urban green spaces and natural corridors. The goal is to create a vaccinated buffer zone that stops the virus from spreading into new territory. Programs like these helped eliminate the dog-associated rabies virus variant in the U.S. and have dramatically reduced fox rabies across western and central Europe.