Rabies: information for veterinarians
Information for Ontario veterinarians on how to assess and respond when a domestic animal may have been exposed to rabies.
Overview
This page provides information for veterinarians about rabies response, including:
- details of risk assessment
- sample submission procedures
- post-exposure management for domestic animals
Animal owners
If you’re an animal owner or member of the public, always contact your veterinarian first if your animal:
- is acting strangely
- may have been exposed to rabies
Report a case of potential exposure
Human exposure
Any exposed person must contact their local public health unit.
If both a human and domestic animal are at-risk, human exposure always takes precedence.
A risk assessment for the exposed animal will occur after public health has addressed the human risk.
Domestic animal exposure (no human exposure)
If a domestic animal is at risk, the animal owner should contact you for a complete risk assessment.
If you need help with the risk assessment, contact a Ministry of Agriculture, Food and Agribusiness (OMAFA) veterinarian through the rabies response request form.
If the offending animal is available and testing is warranted, you must contact OMAFA for shipping and laboratory submission information.
Neurological domestic animal suspected of having rabies
If a neurological domestic animal is suspected of having rabies, you should carefully question the owner about potential exposure to the animal's saliva, as there is almost always some risk that a person or other animal has been exposed (in which case, refer to human exposure or domestic animal exposure).
If an animal with signs of neurologic disease dies or is euthanized and rabies is a differential diagnosis, testing will only be recommended if there was exposure of a person or another live domestic animal.
If there is no risk to other people or animals, testing is done at the discretion and expense of the owner/veterinarian.
Abnormal wildlife with no domestic animal or human exposure
To report abnormal wildlife with no domestic animal or human exposure, contact the Ministry of Natural Resources (MNR) Rabies Information Line at
The MNR performs limited surveillance testing of terrestrial wildlife in certain areas, depending on the time of year. The MNR is only involved in control of terrestrial rabies and therefore will not test bats for rabies.
The MNR will not send staff to capture or dispatch an abnormal animal. If the animal is suffering or threatening people or property (including domestic animals), contact the local animal control authority or the police.
Fights between domestic animals
If there is a fight between domestic animals (for example, between 2 dogs or cats), there is no need for further action unless there is reason to believe that one of the animals has or may develop rabies. For example, if an animal has acute neurologic signs, or it has traveled to a high risk area in the last 6 months.
If a human has been bitten, the incident must be reported to the local public health unit for appropriate follow-up.
What to do if a patient is exposed
The first step following a potential rabies exposure, beyond dealing with the animal's immediate medical needs, is to perform a complete risk assessment.
If the assessment indicates a significant risk of exposure to rabies, consider options for testing and/or post exposure management.
Risk assessment information
A basic risk assessment includes 4 primary elements:
- category of exposure
- offending animal species
- local rabies epidemiology
- animal behavior (assessed within the context of the incident)
The vaccination status of the at-risk animal is not considered at this point. The initial assessment is for the risk of exposure to rabies, whereas vaccination status of the at-risk animal affects the risk of developing rabies. Vaccination status is one of the critical elements in determining post-exposure management of an exposed animal.
Use the rabies risk assessment flow chart to help you through the process.
Category of exposure
The World Health Organization defines 3 categories of exposure based on the potential risk of rabies virus transmission. Only categories 2 and 3 are considered a risk for rabies virus transmission.
The categories are:
- Category 1: touching, licks on intact skin
- Category 2: nibbling uncovered skin, minor scratches or abrasions that may have had contact with saliva.
- Category 3: Transdermal bite(s) or scratch(es) that may have had contact with saliva, licks on broken skin, or contamination of mucus membranes with saliva (such as licks)
Offending animal species
If the offending animal is a rabies reservoir species, the exposure is considered higher risk. Rabies reservoir species in Ontario are:
- bats
- raccoons
- skunks
- foxes
Other species are of significantly less concern unless the animal is displaying neurologic signs. These include:
- coyotes
- groundhogs
- muskrats
- beavers
- opossums
- squirrels
- rats
- mice
- chipmunks
- rabbits
- dogs
- cats
Local rabies epidemiology
More recent cases of rabies in the area increase the risk of exposure of other animals.
Since there are different circulating rabies virus strains, certain reservoir species in some areas are considered higher risk than in others.
There is a low risk (estimated 2 to 3%) of rabies in bats anywhere in the province (bat strain rabies)
Skunks and foxes are of greater concern in northern regions and potentially in Perth county, Huron county and parts of Waterloo Region and Wellington county (fox strain rabies).
Raccoons and skunks are higher risk in the Niagara region and surrounding areas, as well as along the border with the U.S. in Niagara and along the St. Lawrence River (raccoon strain rabies).
Browse through a list of confirmed cases and cases by animal type in Ontario.
Offending animal behavior and circumstances of the event
Abnormal behaviour increases the likelihood that the offending animal may have clinical rabies and therefore the risk that it could transmit the virus. However, it is important to evaluate the animal's behaviour in the context of the incident.
Nocturnal animals are not normally seen during the day, but if disturbed or driven to search for food due to harsh seasonal conditions, they may venture out during daylight hours. Similarly, animals that hibernate such as skunks and bats should not be seen during the winter, but they will come out if disturbed (such as bats in the attic of old houses disturbed by renovations).
There could be other potential causes for seemingly unusual behaviour, such as:
- normal territorial behaviour
- defense of young
- desensitization of wildlife to humans (for example, raccoons that appear overly friendly may have become accustomed to being fed by people in urban areas)
There could also be other potential causes for truly abnormal behaviour, such as:
- canine distemper (affects raccoons, foxes and skunks)
- severe mange infestation
What to do if a patient is exhibiting signs compatible with rabies
Inclusion of rabies on the differential diagnosis list for an animal with clinical neurological disease requires sound professional judgment. Consider the following factors.
Risk of previous exposure to a rabid animal
Observed encounter
In some cases, animal owners may report an observed encounter with wildlife, typically within the last 6 months. The risk of rabies transmission from such an incident should be evaluated according to the risk assessment information.
Unobserved encounter
If there was no observed encounter, it is important to consider the risk of an unobserved encounter.
This risk will be higher for animals that are allowed to roam outdoors off leash or entirely unsupervised, particularly in areas where rabid animals have recently been found.
Travel to other countries is also a risk, including some areas of the U.S. where there is a higher level of endemic rabies.
Also consider the potential for exposure to bats, even for animals that are entirely indoors.
Clinical course
Clinical signs of rabies are always progressive, and without medical intervention the vast majority of infected animals will succumb within approximately 10 days of signs appearing.
If the animal's clinical course has been waxing and waning, or lasted longer than 10 days, then rabies is unlikely.
Animals that have purely spinal neurological deficits are also far less likely to have rabies, although spinal rabies can occur very rarely.
Vaccination history
Although no vaccine offers 100% protection, modern rabies vaccines are extremely effective.
If the animal's vaccination status is, and has been, up to date for at least the last 6 months, then clinical rabies is significantly less likely.
If an animal was only recently vaccinated for the first time, or only recently revaccinated following a lapse in the regular revaccination schedule, then the risk is higher, as the animal could have been exposed to the virus earlier while relatively unprotected.
Other differential diagnoses
If there is another apparent cause for the animal's neurological signs, then rabies is significantly less likely. Consider other differentials such as:
- trauma
- neoplasia
- sepsis
- bacterial or fungal infections
- viral infections (such as canine distemper)
If rabies is a differential for the animal's condition, the risk of exposure of any or other domestic animals to the patient's saliva up to 10 days prior to the animal first exhibiting neurological signs or any behaviour change must be evaluated.
If there is potential for human exposure (which is common in the case of any pet), then the local public health unit must be contacted as well.
All reasonable precautions should be taken to avoid further exposure of staff, owners and other animals to the patient's saliva. The animal will not be ordered destroyed by either the provincial or federal authorities assuming it can be safely confined. However, if the animal dies or is euthanized (as decided by the owner), then testing for rabies may be required if there has been a significant exposure.
Sample submission and testing
Rabies testing is performed by the Canadian Food Inspection Agency (CFIA) at laboratories in Ottawa, Ontario, and Lethbridge, Alberta.
The required sample depends on the animal species being tested:
- for animals less than 500 g (such as bats or small rodents), send the entire animal
- for animals less than 100 kg (such as dogs, cats, raccoons or foxes), send the entire head, do not remove the brain
- for animals greater than 100 kg (such as livestock), send the entire brain
The Ministry of Health (MOH) has a contract with the Ontario Association of Veterinary Technicians (OAVT) to have registered veterinary technicians (RVTs) collect and submit samples on behalf of public health units under the OAVT Rabies Response Program (RRP). The program is only used by public health for submitting samples in cases of potential human exposure to rabies.
For cases in which potential domestic animal exposure has occurred, but there is no human exposure, local veterinary or animal control personnel should collect and ship the samples. Facilities should submit a request to OMAFA for help through the rabies response request form. If it is confirmed that testing is warranted, OMAFA will provide the necessary shipping and submission information. There is no cost to the owner or clinic for shipping or testing in these cases.
In cases where other diagnostic tests or a full post-mortem on a domestic animal are requested and the animal is sent to the local diagnostic laboratory (such as the Animal Health Laboratory), the sample for rabies testing can be sent by the local laboratory to the CFIA. In these cases, there is no additional expense to the client for sample collection or submission for rabies testing, but transportation to the diagnostic laboratory, post-mortem fees, disposal fees and other diagnostic tests are at the expense of the animal owner.
Find detailed sample collection and submission instructions and videos.
Post-exposure management
If the offending animal is not available for testing or if testing confirms rabies infection, then post-exposure management options need to be considered. The recommendations provided by OMAFA are based on previous recommendations used by the CFIA and currently available scientific evidence. The management recommendations can be enforced under the Animal Health Act if they are not adhered to voluntarily.
The length of the post-exposure management period in dogs and cats depends on the vaccination status of the at-risk animal at the time of exposure, and ranges from 45 days to 6 months. Details on the management recommendations are in Table 1.
| Vaccination status | Recommendations |
|---|---|
| Animal fully vaccinated for rabies (received at least 2 consecutive vaccines according to the label directions for technique and interval, and is still within the label interval) |
|
| Animal primarily vaccinated for rabies (only received one rabies vaccine and not yet due for 12-month booster) |
|
| Animal not up to date with rabies vaccination (previous rabies vaccine is expired according to label directions) |
|
| Animal never vaccinated for rabies or with unknown rabies vaccination history |
|
Observation periods and precautionary confinement periods
Observation period
General recommendations for an observation period:
- minimize the animal's contacts outside of the household
- dogs are allowed to leave the property with a responsible age-appropriate handler but must be kept on a leash at all times
- keep cats indoors at all times
Precautionary confinement period
General recommendations for a PCP:
- keep the animal on the owner's property at all times, unless medical attention is required
- limit contact with the animal to one age-appropriate caretaker
- prevent contact with other people or animals
- only allow dogs to go outside on a leash and in a fenced area (double barrier to escape)
- keep the animal in a secure indoor area that:
- allows the caretaker to observe the animal before direct contact
- prevents accidental escape when indoors (for example, double door entry)
Read the recommendations that should be provided to a dog or cat’s caretaker for a PCP.
For a fillable PDF version of the PCP recommendations, email ag.info.omafra@ontario.ca.
Post-exposure management: livestock
Post-exposure management of livestock (cattle, horses, small ruminants) depends on the origin of the offending animal, but not the at-risk animal’s vaccination status.
Outside of herd/flock
If the offending animal originated from outside the herd/flock, a 60-day PCP is recommended for any potentially exposed livestock.
For example, an abnormal fox found in a sheep barn that may have bitten several animals.
Within herd/flock
If the offending animal originated from within the herd/flock, a 40-day PCP is recommended for any potentially exposed livestock.
For example, a cow within the herd developing neurological signs and rabies is a differential diagnosis
Other considerations
Issues such as use of working animals, use of animal products such as milk and shipping of animals to slaughter (including cull animals) during the PCP require careful consideration. These are generally evaluated on a case-by-case basis based on consultation between the attending or herd veterinarian and OMAFA staff.
Submit a request to OMAFA through the rabies response request form.
10-day public health observation periods
According to Health Protection and Promotion Act, Regulation 557 3(2), (2.1), any domestic mammal that bites a person and is reported to the local public health unit is placed under an observation period of either:
- 10 days for dogs and cats
- 14 days for most other domestic animals
If the animal remains clinically normal at the end of this period, the risk that it could have been shedding rabies virus in its saliva when the bite occurred is negligible and the victim of the bite therefore does not require post-exposure prophylaxis for rabies. These short observation periods are for the benefit of the human victim.
Euthanasia
Domestic animals must not be euthanized during a public health observation period for anything other than humane reasons.
If the animal dies within this time period, you must inform the local public health unit so that they can perform rabies testing.
Vaccinating
Animals are also not to be vaccinated during a public health observation period. However, the incubation period for rabies in dogs and cats can be up to 6 months. If a pet is the victim of a bite from a wild animal that may have rabies, the recommended confinement period is much longer than 10 days.
When to vaccinate
If a client reports a potential rabies exposure of a domestic animal, a complete physical exam and booster rabies vaccination are recommended. Vaccinating an animal post-exposure is based on the same principle as post-exposure prophylaxis vaccination in people. Boosting immunity before the virus spreads from the local site of inoculation can help prevent it from reaching the central nervous system.
The only time an animal cannot be vaccinated for rabies (other than for a medical contraindication) is when it is under a 10-day public health observation period for biting a person.
Contact us
If you’re a veterinarian and you need help with a specific case, contact us through the rabies response request form.
You can also contact the Agricultural Information Contact Centre at
- the rabies response request form
- assessment and procedures
- post-exposure management recommendations