What is Rabies?
Rabies is a very serious viral infectious disease. It is a zoonotic disease which means all mammals, including humans, are susceptible.
How is Rabies Transmitted?
Rabies is transmitted by infected saliva, most commonly via animal bites. Infected raccoons and skunks are common animals that are known to bite and spread the disease to pets. Once introduced, the virus travels up the peripheral neurons (neurons that supply sensation to skin and skeletal muscles) to the central nervous system, which includes the brain and spinal cord. It is able to spread to other tissues through the sensory and motor neurons located throughout our whole body including the salivary glands. The typical incubation period (the time of exposure to the onset of symptoms) can range anywhere from a few days to a couple months. An incubation period of 1-2 years is quite rare, but has been reported.
What are Symptoms of Rabies?
The initial clinical symptoms that begin after the incubation period are behavioral changes, such as anxiety, irritability, distress, nervousness, etc. This is called the prodromal phase and typically lasts between 2-4 days. There are two forms of symptom progression, furious form and paralytic form. Pets infected with rabies may experience one or both forms.
Clinical Symptoms of Furious Form Include:
- Aggression
- Compulsive roaming
- Chewing or eating strange objects
- Restlessness
- Fear of light (photophobia)
- Poor coordination
- Disorientation
- Seizures
Clinical Symptoms of Paralytic Form Include:
- Onset of progressive muscle paralysis starting at the site of infection
- Excessive drooling/salivating
- Inability to breath
- Coma
- Death
How is Rabies Diagnosed?
The only way to definitively diagnose rabies is through evaluation of brain tissue post-mortem. The direct fluorescent antibody (DFA) test is the gold standard for diagnosing rabies in the United States. This test is able to detect the presence of the rabies virus antigen.
The presence of Negri bodies within nerve tissue is indicative of rabies. They do not appear in all infected neurons and therefore should not be used as a routine diagnostic method for detecting rabies because of the potential for false negatives.
Veterinarians are required by law to notify the public health department of suspected rabies cases. Public health department rules and regulations can vary from state to state, but are typically similar.
Is There a Treatment for Rabies?
There is currently no treatment or cure for rabies once symptoms appear. General national guidelines for rabies recommend the following:
- An unvaccinated pet with a bite wound from an unknown source should be placed under supervised quarantine for a minimum of 6 months or euthanized.
- A vaccinated pet with a bite wound of unknown source should be re-vaccinated within 3-5 days after possible exposure.
- An unvaccinated pet who bites a person/or another pet should be quarantined for 10-14 days and observed by a veterinarian for clinical symptoms indicative of rabies.
If a pet dies or is euthanized within 10-14 days after biting a person, the law requires that the brain tissue be sent out to the lab and tested even if the pet is up to date on their rabies vaccines.
Although there is no treatment for rabies in pets, there is a series of post-exposure vaccines available for humans administered the day of exposure and on day 3, 7 and 14, for a total of 4 doses. In the unlikely scenario that you are bitten by a wild animal, whether it is displaying clinical symptoms of infection or not, immediately notify your doctor.
What Can I Do to Prevent Rabies?
The initial vaccine should be administered at around 3-5 months old with a booster shot one year after the initial dose. After that, a booster is required every year or three years depending on which vaccine is administered.
Puppies and kittens that have not yet received the rabies vaccine should remain inside and isolated from other animals until they are old enough to be vaccinated. Speak with your veterinarian for more information about the rabies vaccines and prevention.
The button below will direct you to the CDC's list of local public department agencies by state.