The first time I saw the word zoonoses in a class syllabus in veterinary school, my mind immediately went to the rubber “animal noses” that my father would buy by the dozens in nature stores and zoo gift shops. Few things amuse Dad more than wandering around with a rubber rhinoceros snout fastened over his own substantial proboscis. (Dad also does a formidable Sam the Eagle impersonation.) Once I figured out that our professor probably wasn’t nearly as excited as I was about donning an eagle beak or alligator maw, I decided that the word had to be a typo – “zoonoses” – it just didn’t look real.
However, zoonoses (the plural of zoonosis) are very real indeed and not nearly as funny as prosthetic monkey faces. Zoion is from the Greek, meaning “animal.” Nosos, from the same language, means disease. Stepping into a present lacking in Doric columns, Socrates, and bowls of hemlock, we find that zoonoses refers to diseases that are transmitted between humans and animals (or, more specifically, between human and non-human animals). Yep, we are neither mineral nor vegetable, nor are we sub-deities or cyborgs. Humans are part of Kingdom Animalia, and as part of the animal kingdom, we are susceptible to an array of viruses, bacteria, parasites, and prions (DNA wanna-bes) that infest and infect everything from mosquito to mammoth.
Every now and then, a zoonosis will hit the media spotlight and veterinarians run around like the excited but slightly distant family of the next reality TV star. We knew toxoplasmosis when he was just a little schizont, lurking in cat poop. Salmonella, E. coli, and veterinarians go way back; we’ve partied together throughout many an all-nighter. Ringworm is good for a laugh when it’s happening to someone else. Rabies? Well, yeah… who doesn’t have a good story about that guy? What an animal! Bubonic plague may have gone incognito after that whole Black Death scandal, but veterinarians know that she’s been spotted wearing sunglasses and a dark wig in the fleas of cats, squirrels and other critters in various parts of the United States.
So how does the medical establishment handle the cross-over between human and non-human animal diseases? After all, you wouldn’t go to your veterinarian for a bad case of diarrhea or a weird rash on your … anything, right? And you probably wouldn’t take your dog to the pediatrician along with your son. Nor would your local mosquito specialist be the first person you’d expect to seek out for advice on that terrible headache. But the world does indeed seem to be shrinking. Forget six degrees of Kevin Bacon; there’s less distance than you might think between Kevin and a slab of bacon.
Advances in vaccine and pharmaceutical technology led to a decrease in the incidence and/or severity of a number of zoonoses. When was the last time you saw plague-ridden corpses being loaded into wheelbarrows complaining “I’m not dead yet,” or knew anyone with recurrent fevers from brucellosis?
However, as discovered in Jurassic Park, “Nature finds a way.” While our world may not be plagued by hordes of velociraptors any time soon, shifts in populations, food supply, economics, and climate are changing the risks of zoonotic disease.
So how do these diseases get handled?
For the last century or so, human and animal diseases have been kept pretty separate, but with incidents such as outbreaks of bovine spongiform encephalopathy (gotta love the image of sponge-brained cows) and West Nile virus, not to mention the numerous reports of food-borne illnesses in the last decade or two, folks in both medical professions are realizing that we need to climb out of our individual hamster balls and play together.
Physicians and veterinarians have made tentative steps toward increased dialogue since the 1960s, but, for the most part, it’s been like middle-school students at their first dance – lined up on separate walls, staring awkwardly and whispering a lot. Every once in a while, a couple will get out on the dance floor and revolve slowly and at an appropriate distance, but pretty much everyone has been waiting for someone else to take the lead.
However, in 2007, the presidents of the American Veterinary Medical Association and the American Medical Association opted to work together to develop a joint effort called One Health Initiative. The basic principle of One Health is that all living things get sick, and that the health of all living things is interconnected. From the One Health Initiative website: The One Health concept is a worldwide strategy for expanding interdisciplinary collaborations and communications in all aspects of health care for humans, animals and the environment.
Recently, a human cardiologist, Barbara Natterson-Horowitz, M. D., published a book titled "Zoobiquity" that charts the parallels between human and non-human animal diseases and makes an eloquent case for the need for a greater dialogue between veterinarians and physicians.
However, these are big-picture, institutional, mysterious-guy-behind-the-curtain issues. On a smaller scale, how do zoonoses touch our own noses (and ears, skin, brains, intestines, etc.)?
Contact between humans and animals happen all the time, so frequently that we may not even think about it.
That mosquito bite? Human/animal contact and potential zoonotic transmission.
Playing with the puppy while eating a sandwich? Ditto.
Sweeping up mountains of rodent… um…offerings, while cleaning the garage/barn/old vacation home? Yep.
Prepping meat for dinner? You guessed it.
The list goes on and on.
Even folks who don’t own pets come into contact with the rest of the animal kingdom on a daily basis – unless you live in a hermetically sealed chamber in Antarctica and are subsisting only on Tang and Twinkies, but if that’s the case there are other health issues at stake.
Should we panic? Rid ourselves of all non-human species and any sickly looking hominid ones while we’re at it? Should we don hazmat suits and bathe daily in hand sanitizer?
Nah. For one thing, the hand sanitizer baths would make shaving a quite literal pain. For another, these diseases are simply part of existence on a living planet. Still, there are things that can be done to minimize the risks of the wrong noses.
Wash hands after prepping raw meat; after playing with puppies, kittens, turtles, lizards, wallabies, giant squid, and small children; after cleaning up your pet’s “business” (really should go without saying); cleaning an aquarium or tank; after gardening; after fairs, petting zoos and aquatic touch tanks; and any other time your mother suggested that you “go wash those hands right now.” This is the single most effective thing you can do to prevent contacting a zoonotic disease.
Ban bugs – mosquitoes and ticks are the FedEx of zoonotic diseases. Talk to your veterinarian about approved flea and tick preventatives for your pets. Take precautions to minimize mosquitoes on your property. Wear bug repellent. Check yourself and your critters for ticks after those lovely summer walks through the idyllic but weirdly insect-infested countryside.
You are what you eat (or, if you’re not careful, it’ll be what eats you) – check out these Safe Food Handling Fact Sheets
from the United States Department of Agriculture.
Only you can prevent … parasites. Certain parasites of animals, such as hookworms, can cause disease in humans, especially kids, who love to get down n’ dirty where the parasites lay in wait for their next ride. Talk with your veterinarian about preventative care for your pet, such as parasite treatment or prevention, especially in puppies and kittens.
Be rabid about rabies
– rabies is one of the most deadly and most preventable zoonoses. Any mammal can become infected with and shed the rabies virus, though some (bats, raccoons, foxes, skunks, coyotes, dogs, cats) are more likely than others (dolphins, narwhals, beluga whales). Rabies vaccination for animals is both cheap and effective; rabies treatment, not so much. Talk with your veterinarian about an appropriate vaccination schedule for your own animals, and counsel family members (especially the smaller ones) about avoiding contact with wild animals, particularly those that look “sick” or “hurt.”
Avoid keeping pet food in areas where you prepare food for yourself or your family. This one is always hard to follow for those who feed their pets in the kitchen or dining room, but many potential bugs can arrive in a bag of kibble or can of dog food.
Special circumstances require special attention – if a member of your family has a compromised immune system (HIV, chemotherapy, transplant, diabetes, advanced age, very young child, pregnancy), talk with both your physician and veterinarian about the best ways to keep everyone in the house healthy.
If you get scratched or bitten, wash the area thoroughly with soap and running water.
Zoonoses may not be the right sort of noses, but teamwork between animal owners, veterinarians, and physicians can diminish the day-to-day risk of these diseases – leaving us free to adopt more entertaining noses. Groucho glasses, anyone?