< Back to blog


5 August 2022

Zoonoses are diseases that can be transmitted between humans and animals. Are all the diseases that can be transmitted to us dangerous? The answer is no, but it is important to know the risks. Several pathogens (e.g. bacteria or parasites) may be present in your pet and thus increase your level of risk of contracting its pathogens and developing health problems.

The good news is that prevention is key.

It is possible to prevent this type of infection in your pet and therefore protect you indirectly.

The first prevention consists in having a responsible behavior with our animal. It is important to have a healthy lifestyle when handling your pet’s stool and urine and to reduce contact between your mouth and his. Don’t forget, your pet tastes everything and licks everywhere… even the buttocks… just this image should convince you!

Another way to prevent disease transmission, and not the least, is to discuss it with your veterinarian. What are the risks for my animal? What should I do to reduce the risks?

We are going to see some diseases that can be transmitted by our pets and how to prevent them.

Prevention through vaccination


It is the most well-known viral zoonosis in Canada, and the deadliest! Rabies infects warm-blooded mammals by entering through bites or is transmitted through contact with saliva or wounds. The wildlife species that are most frequently infected are skunks, raccoons and bats1. The symptoms that can be observed with rabies are variable but generally they are neurological (eg weakness, fever, tremors, difficulty breathing and swallowing then death). A dog, cat or ferret that has been in contact with an infected animal can have the rabies virus in its saliva for up to 10 days before showing symptoms. An animal can therefore transmit rabies even if it appears healthy.

If you are the owner of a domestic animal, such as a cat or a dog, it is strongly recommended to have it vaccinated against rabies, from the age of 3 months, whether it goes outside or not2. When a pet bites a human, it is the responsibility of the owner of that animal to keep it in isolation and observation for a period of ten days in order to watch for a change in behavior or signs of illness compatible with those of rage. In addition, anyone who has been bitten by an animal must immediately contact a health professional or Info-Santé (811)3.


Leptospirosis is an increasingly well-known disease caused by a bacterium (Leptospira) which is excreted in urine and contaminates rivers, ponds and streams. This bacterium has several subclasses (serovars) that produce different types of disease and are found in different geographical areas. The animals most often affected are wild animals such as raccoons, city rats, and of course dogs, since they drink outdoor water and bathe frequently. Effectively, dogs or people infected with Leptospira become contaminated when the skin is irritated or cut and comes into contact with infected urine or water contaminated with infected urine. Cats can also contract the infection, but rarely show symptoms of the disease. The organs most affected by serovars are the kidneys, liver and eyes. There are acute and chronic forms. Prevention of illness includes avoiding contact with the urine of infected pets or contaminated food and water, and practicing good hygiene. A canine vaccine is available to prevent this disease.

Prevention by deworming


Also called Toxascaris or Toxocara, is a parasite frequently encountered in puppies and cats. Transmission takes place via the mother. It looks like a long spaghetti. It is among other things for this parasite that a deworming is recommended monthly in puppies and kittens from the age of 2 months. A stool analysis is also recommended to find out your animal’s parasite load and if it is currently excreted eggs in its stool. The treatment protocol could therefore be adjusted according to the results. Does your pet not go outside? He is less at risk of contaminating himself, but the risk is not zero. The risk for humans consists of the ingestion of the eggs. Remember that there is potential for contamination when your pet licks your mouth… People who swallow eggs can become infected. Once in the intestine, the eggs hatch and develop into larvae. These sometimes interfere in the intestinal wall and move through the body. Migration of the larvae into the abdomen causes disease (called visceral larva migrans). Unmatured worms that reach the eyes can cause blindness (called ocular larval migrans). This phenomenon of larva migrans is also well known in cats. Your indoor cat should also be dewormed regularly. Children are more susceptible to worms than adults because they play on lawns and in sandboxes where contaminated faeces are more commonly found1. The best way to protect yourself is to deworm our animals regularly and establish a healthy lifestyle. Wash your hands, we never say it enough!

Lyme disease

A spirochete is the causative agent of this famous tick-borne disease. It is not really a zoonosis but I still wanted to discuss it with you because our animals can still contribute to the transmission of this disease indirectly. First of all, there are thousands of species of ticks, but only some can carry Lyme disease. Ticks become active at an outside temperature above 4 degrees. This means that they can be present even in winter. Year-round protection is therefore recommended for dogs and cats going outside. Dogs, unlike humans, are relatively resistant to this infection and more rarely become symptomatic. However, they can develop joint or kidney symptoms for several months or even a few years following contact with a tick. An annual screening test is therefore recommended to ensure that the protection we offer our pet is suitable for him. For humans, weeks to months after infection, about 60% of people will experience intermittent arthritis attacks and 5% will develop chronic neurological manifestations. In humans, Lyme disease can lead to serious long-term illness4.

How protecting our animals against ticks protects us against Lyme disease?

What we want to avoid is that the female tick feeds on our animal, detaches itself from it once the meal is over and lays its eggs in our immediate environment. Isn’t it better that she dies before she lays her eggs?

It is therefore preferable to use drugs that kill ticks rather than repellents.

These products require a prescription from your veterinarian, but they are more effective and would be more suitable for your pet than an over-the-counter product. In addition, you will have access to a medical team to optimally prevent the disease for the animal and for you. The INSPQ is mandated by the Ministry of Health and Social Services to offer an integrated surveillance program for Lyme disease in Quebec (report in French). This surveillance program makes it possible to follow the evolution of the risks of acquiring Lyme disease in Quebec in order to support public health authorities in their risk management. It also provides information on sectors at risk of acquiring the disease in order to increase the vigilance of health professionals and the public. The Capcvet site is also available to find out which regions are most at risk. You will therefore be able to see what the level of risk is at home, whether you live in the countryside or even in the city.

Very often, zoonoses can be avoided by simple actions and effective prevention. Do not risk the health of your loved ones and contact your veterinary team to obtain solutions adapted to the level of risk of each of your pets.

Dre Chantal Riendeau D.M.V.

1 https://www.canadianveterinarians.net/related-resources/zoonoses-shared-disease-agents-of-people-and-pets/
2 https://www.quebec.ca/en/health/health-issues/a-z/rabies-in-humans
3 https://www.quebec.ca/en/agriculture-environment-and-natural-resources/animal-health/animal-diseases/rabies-in-animals
4 https://veterinarypartner.vin.com/doc/?id=4952009&pid=19239

Photo credits
Shvets and Cottonbro on Pexels