Rabies in Dogs

Rabies is caused by a group of viruses called lyssaviruses, capable of infecting essentially any warm-blooded animal, including humans, which is part of why rabies is one of the most widely recognized viral diseases in the world. It causes inflammation of the brain, and worldwide, it remains a serious public health threat: the World Health Organization estimates roughly one person dies from rabies every 9-10 minutes globally, largely in regions without reliable access to vaccination.

The time between exposure and the first symptoms usually falls between 1 and 3 months, though it can range from under a week to over a year. That variation comes down to how far the virus has to travel through the body to reach the central nervous system.

Rabies spreads almost exclusively through a bite from an infected animal. Rarely, it can also spread through scratches or via infected saliva contacting mucous membranes. Among wildlife, foxes, coyotes, skunks, raccoons, and bats are the most common carriers. In caves densely populated with infected bats, transmission through inhaled aerosolized virus has even been documented.

The virus doesn't survive long outside a host. It remains viable for less than 24 hours in the body of a deceased infected animal. While an infected animal's saliva carries high concentrations of the virus, a bite doesn't guarantee infection in the bitten animal or person.

After infection, a dog may go through several distinct stages. Initial signs often include itchiness at the bite site and fever, as the virus begins traveling slowly along peripheral nerves toward the brain. In dogs, the average time from exposure to brain involvement is 3 to 8 weeks, though incubation periods of up to 6 months have been documented. Once the virus reaches the brain, it moves on to the salivary glands, where it becomes transmissible to another animal through a bite.

• Prodromal phase

  In dogs, this initial phase typically lasts 2 to 3 days. Behavioral shifts like apprehension, nervousness, anxiety, or a tendency to withdraw often appear, sometimes alongside a fever. Normally friendly dogs may become shy or irritable and may snap or nip, while normally aggressive dogs can become unusually affectionate and docile. Dogs often fixate on the bite site, licking or rubbing it repeatedly.

• Furious phase

  This phase, when it occurs, typically lasts 1 to 7 days in dogs. Affected dogs become restless, irritable, and hyper-reactive to sounds or visual stimuli. As restlessness builds, they may wander, growing progressively more irritable and potentially aggressive. Dogs that are confined may bite or attack their enclosure. Disorientation and seizures follow, ultimately leading to death.

• Paralytic phase

  Some dogs develop this third phase, either following the prodromal or furious stage, usually within 2 to 4 days of the first symptoms. Paralysis develops as the virus affects motor neurons, typically starting with the nerves controlling the head and throat. Affected dogs may lose the ability to swallow, leading to visible drooling. As paralysis spreads to the diaphragm and facial muscles, breathing becomes labored and the jaw may hang open, sometimes producing a choking sound. As muscle control continues to fail, the dog weakens progressively until respiratory failure occurs.

Currently, rabies can only be confirmed through microscopic examination of brain tissue, meaning definitive diagnosis happens after death. Newer testing methods using skin or blood samples are in development for live animals, but aren't yet in routine clinical use.

If your dog is bitten or scratched by wildlife that isn't available for testing (including bats), treat it as a probable rabies exposure.

• If your dog is unvaccinated

  Current CDC and NASPHV (National Association of State Public Health Veterinarians) guidance recommends euthanasia as the safest course of action, since no licensed treatment can guarantee an unvaccinated exposed dog won't develop rabies. If the owner declines euthanasia, the recommended protocol is immediate vaccination followed by strict quarantine for 4 months. Individual states can have their own legal requirements that may differ, so confirming your local jurisdiction's specific rule is worthwhile.

• If your dog is currently vaccinated

  The standard protocol is a booster vaccination as soon as possible, followed by a 45-day observation period at home under your control, rather than strict isolation.

If a dog bites a person and rabies is a concern, standard protocol is a 10-day observation period to watch for signs of illness, rather than immediate euthanasia. This allows time to confirm whether the dog was actually infectious at the time of the bite. Specific requirements can vary based on the dog's vaccination status and local regulations.

People bitten by a potentially rabid animal are typically given a series of post-exposure vaccinations along with a rabies immunoglobulin injection. If you're bitten by any animal that might carry rabies, wash the wound thoroughly with soap and water for a full 15 minutes, then seek medical attention immediately.

Vaccination remains the only reliable way to prevent rabies, and when kept current, it's highly effective. Rabies vaccination is legally required for dogs in all U.S. states, yet a significant portion of the dog population remains unvaccinated or overdue.

The standard vaccination protocol is a first dose at 3 to 4 months of age, a follow-up dose one year later, and then a 3-year vaccine after that, which has proven highly effective long-term. Your veterinarian can tailor recommendations to your dog's specific situation.