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When most people think of rabies, they picture snarling animals with frothy saliva. While that image captures the severity of the disease, it is not always accurate. Rabies is a lethal viral infection that can affect any warm‑blooded mammal, including squirrels. Understanding its clinical presentation is essential—especially if you encounter wildlife.
Rabies—caused by the Lyssavirus—is a neurotropic virus that targets the central nervous system. It is zoonotic, meaning it can jump from animals to humans. Transmission typically occurs when an infected animal’s saliva comes into contact with a bite wound or a mucous membrane (eyes, nose, or mouth).
Once clinical signs appear, the disease is almost invariably fatal. Fortunately, timely post‑exposure prophylaxis (PEP) is highly effective. PEP consists of human rabies immune globulin (HRIG) and a series of four to five rabies vaccinations administered immediately after the exposure.
While the virus can infect any warm‑blooded mammal, the risk varies. Small mammals such as squirrels, rabbits, mice, rats, moles, hamsters, guinea pigs, gerbils, and chipmunks are generally low‑risk. Bites from these animals rarely warrant special precautions for rabies.
High‑risk species include raccoons, skunks, foxes, coyotes, and bats. Domestic animals—cats, dogs, and livestock—can also be high risk if they have not received vaccination. In the event of a bite from a high‑risk animal, the animal is often quarantined for 10 days to monitor for disease onset.
Encountering a rabid squirrel is uncommon, but recognizing the disease’s hallmarks is valuable. Rabies induces encephalitis—brain inflammation—which manifests as paralysis, blindness or photophobia, loss of balance, aggression, confusion, and behavioral changes. The classic “foaming” at the mouth usually reflects paralysis of the throat or jaw muscles and is not always present.
Unexpected behavior is a key indicator. Animals may become violently aggressive or, conversely, unnaturally docile, abandoning their natural wariness of humans. Similar signs can arise from distemper or brain‑affecting roundworm infections, so any abnormality warrants caution.
Wild animals can carry the virus for months before showing symptoms. Therefore, the safest approach is to avoid contact with squirrels displaying unusual behavior. If you are bitten or exposed to saliva, seek medical advice immediately.
