Zoonotic Diseases of Dogs: You may have heard the term “zoonotic” and wondered what exactly does that mean? Zoonotic diseases are diseases that can be transmitted from animals to humans. In this article we will focus specifically on diseases that have the potential for being transferred from your dog to you or other people and what you can do to prevent this from happening.
Rabies is a deadly virus that can be quickly transmitted through the bite or saliva of an infected dog. Thankfully, due to laws in place requiring dogs to be vaccinated for rabies, the virus is extremely rare in dogs in North America. However, it is still present in wildlife, and if your dog is not up to date on their rabies vaccine, they are at risk of acquiring it by coming into contact with wildlife, and can then transmit it to people. Additionally, rabies is still a cause of human death in other parts of the world, where vaccine campaigns have not been able to take off.
The best way to prevent your dog from getting rabies is to keep your dog up to date on their rabies vaccines and to prevent them from coming into direct contact with wild animals, such as raccoons, skunks, foxes, and bats. If they do come into direct contact with one of these wild animals, always have them evaluated by your veterinarian right away as they may need to have a booster of their rabies vaccine, even if they were just vaccinated a few months prior.
If you come across a stray dog that is acting off or just doesn’t seem quite right, it is best to call animal control and let them come to get it, instead of risking you and your family’s health.
Roundworms are intestinal parasites that dogs can acquire either from their mother or by coming into contact with soil or other dogs’ stools that are infected. Dogs can ingest the roundworm eggs or larva through their mouth and then pass the worms and their eggs in their stool. Sometimes you can’t even see any worms in their stool, as they are only passing microscopic worm eggs.
If a person comes in direct contact with the infected soil or stool, there is a chance the person can inadvertently ingest them and become infected. This is more of a concern for children since they like to play in dirt and put things in their mouths. In children and adults, roundworms can migrate to various organs in the body, causing them to become sick. They can sometimes even migrate to the eye, having the potential to cause blindness.
It is for this reason that it is highly recommended to always pick up after your dog when on walks and when let out to defecate in your yard. Leaving the stool to sit on the ground provides a nourishing environment for these worm eggs to thrive and hatch, putting children at risk of becoming infected, and putting your dog at risk of continuously re-infecting themselves.
Other ways to prevent this is to keep your dog on monthly heartworm and parasite prevention, and even have your dog’s stool examined by your veterinarian every year. Additionally, maintaining good hygiene and washing your hands after picking up after your dog, after playing outside or gardening, and always prior to eating are good means of prevention.
Just like roundworms, hookworms are transmitted to puppies from their mothers and to dogs by coming into contact with contaminated soil or remnants of other dogs’ stool. However, people become infected with hookworms in a different way than they do with roundworms. Hookworm larva can actually penetrate a person’s skin and then migrate through their skin, causing itchiness and infection. This usually happens when someone walks outside barefoot and steps in an area where a dog, who had hookworms, defecated. This does not necessarily mean they have to directly step on dog stool, as the larva can survive in the soil even if the stool is no longer there.
Therefore, the best way to prevent this is by wearing shoes outside, especially in areas where a dog may have defecated. Additionally, keeping your dog up to date on their monthly heartworm and parasite prevention is key, as well as having your dog’s stool evaluated by a veterinarian yearly to make sure they don’t have any parasites. Finally, always use a scooper or plastic bag to pick up your dog’s stool right after they defecate and put it in a trash can……. then wash your hands!
Ringworm is actually a fungus, not a worm. It gets its name because it causes a worm-like lesion in the shape of a ring on your body. It can be spread through direct skin-to-skin contact or even through being aerosolized, infecting the skin and causing itchy scabs. It’s more of a concern for people with compromised immune systems, as their body can have a harder time fighting it off.
If a dog in the home has ringworm, it can be fairly easy to transfer to susceptible people just by petting the dog or even from coming into contact with contaminated fur lying around the home. Dogs can become infected with ringworm either by direct contact with other dogs or cats, or by being groomed with infected grooming supplies. Ringworm is not always itchy in dogs, and can sometimes be more of a problem in dogs with compromised immune systems, just like people. Sometimes the only sign of ringworm in dogs is a circular area of hair loss with a red scab-like lesion around the outer edge of the circle.
If you are concerned your dog may have ringworm, have them examined by your veterinarian so they can do a test to confirm whether or not ringworm is likely to be present. Generally speaking, ringworm is not very common in our pet dogs, but it is always a good idea to have them examined if you are concerned it could be a possibility. As a precautionary measure, do not directly touch the area in question on your dog and wash your hands and your dog’s bedding frequently.
If you or someone in your household develops skin lesions that resemble ringworm, always check with your human doctor to get diagnosed and started on medications, if warranted.
There are a few different types of mites that like to live on dogs, but one in particular that has the potential to be spread from dogs to people is called Scabies. Scabies (sarcoptic mange) mites are spread dog to dog through direct contact and they cause your dog to be extremely itchy. They can cause a lot of fur loss, scabs, and secondary skin infections as well.
People can acquire this skin mite from petting or coming into contact with an infected dog. It can cause severe skin lesions and itchiness in people. If you or anyone in your family suspects they may have Scabies, go to your doctor to be evaluated. If your dog is not extremely itchy, however, it would be highly unusual that you would have acquired mites from them.
A skin scrape (scratching the surface of the skin with a blade and looking at the cells under a microscope) is performed to diagnose Scabies in dogs, though sometimes the mites may not be seen in the sample taken. Therefore, your veterinarian may decide to treat your dog for Scabies based upon their clinical signs, even if they didn’t see any mites on the skin scrape. Treatment used to consist of medicated dips, but these days there are topical applications and oral chewable tablets that can be given to treat your dog for Scabies.
Campylobacter, Salmonella, & E. coli
Campylobacter, Salmonella, and E. coli are all bacterial organisms that, if your dog is infected with, have the potential of being transferred to people if proper precautions are not taken. Dogs who eat foods contaminated with these bacteria, even if the dog doesn’t get sick, can spread these organisms in their stool. If a person inadvertently comes into contact with the dog’s stool or fur with remnants of stool, that person could become sick with vomiting, stomach cramps, and/or diarrhea.
It is rare for dogs to be infected with these organisms unless they eat contaminated food or are fed a raw food diet. In the veterinary community, it is recommended against feeding your dog raw food diets, partly because of this risk of harmful bacteria infecting children and people with compromised immune systems in the home. However, if your dog needs to be on a raw food diet, make sure to always wash your hands after preparing their food and after cleaning up their stools. Also, immediately after each feeding, thoroughly wash their food and water dishes with warm, soapy water.
Leptospirosis (lepto) is a type of bacteria that is transmitted in the urine of wildlife, such as rodents. You may have even heard your veterinarian mention the word “lepto” before, as there is actually a vaccination available to protect your dog against leptospirosis and it is included in most of the parvo/distemper vaccines that dogs receive nowadays. Your dog may become infected with leptospirosis by coming into contact with contaminated water sources, even just puddles of water in the street or backyard.
Most dogs who become infected can get very sick, developing kidney and liver disease, and possibly dying. Some dogs may develop a mild infection and can recover with the right course of treatment with antibiotics and supportive care. Any dog who is infected, though, has the potential to spread the bacteria in their own urine, putting their humans at risk of infection as well. If your dog has been suspected of having leptospirosis, you have to be very careful when taking them outside to urinate, avoiding coming into direct contact with their urine, and washing your hands frequently to decrease the risk of you being exposed as well.
The best way to prevent your dog acquiring leptospirosis, though, is to make sure they are up to date on all of their vaccinations, including their leptospirosis vaccine, which must be given yearly.
Zoonotic diseases can definitely sound scary, but if the proper precautions are taken, they should not be a barrier affecting the relationship between you and your dog, and hopefully you will never have to be affected by any of them.