World Zoonosis Day is observed each year in July. Although it sounds like we should be celebrating, we need to take a closer look at what “zoonosis” means. A “zoonotic” disease is one which is transmitted to humans from animals. Rabies is perhaps the best-known example, but there are many others as well, all of which can have serious consequences for our health. “The good news,” says Dr. Arnie Cary, DVM, and board member of The Animal Haven in North Haven, “is that proper and normal hygiene, common sense, and routine veterinary care, including vaccinations for our dogs and cats, is usually all it takes to keep both us and them safe.”
Rabies is the most serious zoonotic disease, and can be fatal to both humans and animals if not addressed in time. To protect yourself and your animals, be sure to follow proper vaccination guidelines for outdoor pets, who are most likely to be exposed to the reservoir of wildlife rabies, but also for indoor cats, who can be exposed to bats that can get inside the house. Always remember to report bites from unvaccinated dogs and cats and any wildlife, especially raccoons, skunks, and fox, by calling your town’s department of public health.
Leptospirosis is a bacterial disease that is carried by rodents, raccoons, skunk, deer, farm animals, and many other mammals. Once infected, these animals pass the bacteria in their urine, contaminating the soil and particularly troublesome, standing water. When dogs drink this water, they can become ill with fever, loss of appetite, vomiting and pass the bacteria in their urine. We can be exposed inadvertently to the urine. Most dogs who are regularly vaccinated for distemper are also vaccinated for leptospirosis, but check with your veterinarian to be sure.
Roundworms are very common in young cats and dogs. The worms lay eggs that are passed in the animals’ feces. If ingested inadvertently by young children (a dirty hand goes into the mouth), the eggs will hatch into larvae that find themselves in an unfamiliar species. Normally they would migrate to the intestine of a dog or cat to become adults. In a young human they can migrate to an eye or the brain and become a major problem. Thorough hand washing is important, as well as covering sand boxes so cats and dogs (and also raccoons) don’t use them for litter boxes. Routine deworming, especially of puppies and kittens, is the best way to prevent roundworm.
Ringworm is another very common zoonotic disease. The name ringworm is misleading because there is no “worm” involved. It’s a fungal skin disease that often shows up in an expanding circular pattern, and affects young pets—and young people—whose immune systems have not fully developed. Cats are a common source of infection for humans, although dogs can be a source of infection as well. Ringworm can be quite contagious. Some cats have very few observable lesions, but can spread the disease anyway. Antifungal medications are needed to speed recovery in both humans and animals.
Toxoplasmosis is a protozoa that grows in the intestines of cats, who pick it up by eating uncooked meat. The eggs are passed in the cat’s stool, and we can be infected when cleaning the litter box and not washing our hands afterward. Humans also can get toxoplasmosis from eating uncooked meat. Most of us will not show any symptoms if infected (at most we might have mild flu-like symptoms), but this is a disease that is especially problematic for pregnant women. It can put an unborn fetus at risk, especially late in pregnancy. The best advice is for pregnant women to avoid cleaning the litter box, do a thorough hand washing after handling a cat, and in general refrain from eating undercooked meat A toxoplasmosis blood test can be administered to women who are in early pregnancy. If positive, it means there are antibodies available to keep the fetus safe. If negative, it means a new cat in the house is probably not a good idea until the baby is born and thriving. Ask your doctor’s office if you have any questions.
Most of these zoonotic problems can be easily avoided by keeping our pets vaccinated, dewormed, and carefully examined on a regular basis by a veterinary professional. Now that’s something to celebrate!