Latest articles

We all need to be ever vigilant when it comes to rabies

Beef 911: This fatal disease is very rare, but animal owners and rural residents 
should always be on the lookout for telltale signs

We don’t hear this disease mentioned very often, but when we do there is a very scary connotation attached to it.

Rabies is virtually always a fatal disease to all mammals, and zoonotic to humans with no curative treatment once clinical signs develop. Only prevention through vaccination and a strong surveillance program have kept incidence of rabies fairly low in Canada.

The biggest reservoirs for the disease across the country are bats, skunks, raccoons, and foxes (red and Arctic). It varies across the country, but Alberta has the most reported diagnosis in bats followed by skunks and then cats. Up north, the Arctic fox can be the source and in Ontario we have diagnosed cases in foxes, raccoons and other animals. As of April 1, 2014 (even though it is still a reportable disease for veterinarians) the federal government downloaded the responsibilities to the individual provinces. This arose suddenly out of a budgetary issue in 2012 with no consultation with our national veterinary group or other affected parties. This is called passing the buck.

There were three other diseases, federal officials either dropped or downloaded including anthrax since it is costly to deal with and is considered endemic in Western Canada. Rabies, however, is the most serious zoonotic disease as anyone — whether in veterinary medicine or agriculture, and even urban folk — are at severe risk if they come in contact with a rabid animal. Globally, rabies still kills 55,000 people annually (mainly in Africa and Asia), so it is critical we maintain surveillance to keep people, pets, and farm animals protected. Veterinary clinics will still be involved, as will the provincial medical officer of health, if there has been any human exposure, such as bites from domestic or wild animals.

Everyone needs to be on the lookout for animals exhibiting abnormal behaviour including aggression, varying forms of paralysis (including inability to swallow), and excessive salivation. Lethargy, vomiting, and anorexia (not wanting to eat) are non-specific signs we can observe with rabies. Other signs can include incessant bellowing in cattle. If clinical signs develop, affected animals will die within 10 days.

Veterinary clinics may be involved, especially in isolated areas of the province, to facilitate this process. If you are suspicious of these clinical signs contact your local veterinary clinic, as they become your first line of defence.

Keep in mind rabies is very rare and many other diseases can mimic it. If any of the clinical signs listed above are seen by veterinarians, rabies is always on the differential list. Cows for instance with wooden tongue or a choke will salivate excessively, and these are two conditions that are treatable yet could at first glance indicate rabies. Likewise horses with choke salivate profusely.

Just because we haven’t heard of it or diagnosed it in a while doesn’t mean it isn’t around. Years ago, a client found a bat alive in daylight hours on his lawn acting very peculiar and unable to fly. It was submitted and was positive for rabies.

Since bats are the main reservoir in many areas, it is always advisable to vaccinate dogs and cats. In other areas of the country, such as Manitoba and Ontario, horses and even cattle are vaccinated in high-risk areas (or if they are going to be moved to high-risk areas).

There are two forms of rabies — the furious form or the paralytic form. Horses, cattle, and bats generally get the paralytic form; cats the furious form; and dogs can get either form. (Do you remember the movie “Old Yeller,” which vividly showed the aggressive form in a dog?)

The World Health Organization categorizes rabies exposure at three different levels.

The first is touching or licking from a rabid animal on intact skin. It is NOT considered exposure to rabies.

The second and third categories range from minor scratches to full depth bites and licks on broken skin. These are considered a potential exposure to rabies and where you would first get medical care and follow the guidance of the public health officer.

We are lucky in Canada because with good surveillance and vaccination of most of our pets the incidence of rabies has been kept quite low. Alberta’s famous rat patrol not only keeps rats out of the province, but does the same for skunks in the southeast part of the province where the rabies incidence is higher. Saskatchewan has had cattle and horses with rabies (especially in the southern part of the province) and provincial authorities there look after surveillance (similar to what happens in Alberta). Watch in your particular region of Canada for guidance from the Office of the Chief Provincial Veterinarian.

Each province may implement it slightly differently, but the overall result should be the same. Provincial medical officers, veterinary clinics, and provincial governments all work together to monitor and keep the incidence of rabies low in Canada.

I always thought with all reportable diseases that practising veterinarians have an obligation to report to the federal veterinary authorities (CFIA) as they took the responsibility over and were the final authority. Apparently they still want to be notified or reported to. It is just they are passing the work responsibility over to the provinces.

Get a salivating animal, one acting abnormally, or showing signs of ascending paralysis checked by your veterinarian. If rabies is suspected they will know what to do.

People who might have been exposed to rabies through a bite or scratch from an animal should seek medical attention and also call Health Link at 1-800 408-5465.

Let’s work together to keep rabies a very rare event in Canada and ensure all inhabitants — people, domestic animals, production animals and wildlife — are safe. (As a side note, birds, amphibians, and reptiles can’t get rabies — and rodents only very rarely.) Watch the news for further developments. For those especially interested, there is an international conference on rabies at the University of Calgary Veterinary Medicine in October.

Everyone — including livestock producers, pet owners, wildlife officers, public health officials, and veterinarians — need to be ever vigilant for the possibility of rabies appearing. Just as this article has gone to press a positive rabid skunk was detected in southern Alberta. It’s the first since 1994 and this discovery shows that surveillance is working.

About the author

Contributor

Roy Lewis practised large-animal veterinary medicine for more than 30 years and now works part time as a technical services veterinarian for Merck Animal Health.

explore

Stories from our other publications

Comments