Wildlife Diseases

October 14, 2010 Print Friendly and PDF

Handbook Contents | Customer Risks | Safety Learning Objectives | Job Risks | Safety Gear | Wildlife Diseases | Carcass Disposal | Resources | ICWDM | Wildlife Species Information


Section four: What you need to know about wildlife diseases

How do you catch them and how could you prevent them?

When you see something like this in your customer's home, what crosses your mind? (After "good things they called me.") This exclusion attempt could mean that the nuisance animals entered the living spaces. Ask if any person or pet came into contact with the wild animal. If that's true, consult with the health department. You may need to submit a specimen for a rabies test. That might change your approach to capturing and removing the animal.

"I was scratched on the wrist while banding a Canada goose. About a week later, another goose scratched off the scab. It took me a few hours to notice that the open wound was completely covered in goose poop. Our field station was a day's helicopter flight away from the nearest hospital, and I'd forgotten a first-aid kit. So I washed the wound as best I could with snow. The next morning, the entire area was swollen and tender and I had difficulty bending the wrist." [He cleansed the wound with whiskey and recovered fully.]

—Arthur Smith, wildlife biologist, SD

Wildlife diseases can be caused by bacteria, viruses, fungi, or parasites. The ones that can be transmitted to people are called "zoonotic diseases" or "zoonoses." There are several different ways you can become infected. Most often, this happens when an infected animal bites or scratches you. Disease agents may enter your body through wounds, or through your eyes, nose, or mouth.

You can also pick up diseases indirectly, when you're bitten by a mosquito, tick, or flea that fed on an infected animal. Mosquitoes spread West Nile virus, ticks spread Lyme disease, and fleas carry plague and typhus.

Some diseases are transmitted through the air, such as hantavirus or histoplasmosis. You can breathe them in, especially while stirring up dust in a confined space. Touching your mouth after you've touched something that's contaminated, or eating infected meat that hasn't been properly cooked, may also cause an infection. This is a significant problem for young children, especially when they're playing outdoors. Their sandboxes, play areas, or toys may become contaminated by the droppings or urine of wildlife. Kids may put soil, wood chips, or droppings into their mouths. Raccoon roundworm is spread this way; the parasite's eggs are found in contaminated soil.


Hopeless? Helpless? No way.

So how can you protect yourself, and make sure you don't bring diseases or parasites into your home? Practice good personal hygiene, wear protective gear such as disposable gloves, disinfect your equipment, maintain your rabies and tetanus vaccinations, and use safe animal capturing and handling techniques. Good hygiene and sanitation will also reduce the chance of developing allergies to animals.

Probably the single most important thing you can do to reduce your risk of catching a zoonotic disease is to wash your hands. Ordinary soap and water will do. Wash your hands the way your parents taught you to, thoroughly and often. And always wash your hands before you eat, drink, or smoke.

Another healthy habit is to avoid contact between your hands and your face, eyes, or mouth. Pay attention when you're eating, drinking, smoking, adjusting your glasses, applying cosmetics, taking medication, and when you sneeze.

Keep your gear clean, too. Many of the objects you handle are often fouled by blood, feces, urine, saliva, or body tissues. If your hands or gloves are dirty, it's easy to contaminate doorknobs, car doors, clipboards, telephones, computer keyboards, faucet handles, and many other objects. The nuisance animal may also have made quite a mess; if you don't offer clean-up services, you may want to tell your customers how to deal with it safely.

After the job...

At the end of the day, clean and disinfect all of the equipment you used with dilute bleach water (a 10% chlorine bleach solution, which is one part bleach to nine parts water) or a household or commercial disinfectant. Wipe down your truck's seat, steering wheel, and door handles. Some NWCOs keep a quart spray bottle of disinfectant in the truck's cab because bleach solutions don't keep long, so it's better to work with small batches. Just don't mix bleach and ammonia, or use bleach to clean up droppings, which contain ammonia. Use a household or commercial disinfectant instead. Antibacterial wipes may seem even more convenient but they weren't designed to kill parasites, fungi, or viruses. Those agents cause all but one of the diseases discussed later.

Consider the time you spend cleaning as marketing effort because some customers will interpret cleanliness as a sign of professionalism and competence.

A few wildlife-related safety tips from the CDC that you may want to share with customers:

  • Teach children never to handle unfamiliar animals, wild or domestic, even if they appear friendly. "Love your own, leave other animals alone."
  • Enjoy wild animals from afar. Never adopt wild animals or bring them into your home. Do not handle, feed, or unintentionally attract wild animals to your home or yard (see below).
  • Don't try to nurse sick animals to health. Do not "rescue" baby birds or other baby animals. They usually don't need it. (Direct questions to a wildlife rehabilitator or DEC Bureau of Wildlife staff.)
  • Before traveling abroad, consult with a health care provider, travel clinic, or your health department about the risk of exposure to rabies. They can advise you about whether pre-exposure rabies vaccinations are sensible, and how you should handle an exposure in that country, should it arise.
  • These CDC tips focus on disease prevention. As we mentioned earlier, you can take measures to prevent nuisance situations while leaving part of your landscape for wildlife. There are many things to consider when managing land for wildlife, including the risk of exposure to wildlife diseases.

Medically important or just media hype? (Some health concerns that affect NWCOs)

Overturned trash cans are a nuisance, but is the situation dangerous? Depends on whether the culprit is a bear or a mouse. To use the best practices approach, you need to think like a detective. Imagine if you saw this scene after the bear left. A careless NWCO might blame the problem on a raccoon and suggest ways to make the cans raccoon-proof. Those measures might not slow down a bear. So the problem, and the safety risk, could continue.

Consider this an introduction to some health concerns that affect NWCOs. For example, you'll often be cautioned to "wear a proper respirator." That's shorthand to alert you to the need to protect yourself from breathing in microscopic disease agents.

How much do you need to know? You're not a doctor, after all. You don't have to be able to throw around words like "sapro-zoonoses," but you do need to know enough to protect yourself and others, and to answer your customers' questions.

Sometimes our fears about these wildlife diseases are much greater than our actual risks of catching them, or the likely results of an infection. Even for an ethical NWCO who's not trying to sell a job by frightening customers with an overblown assessment of the risk of catching a wildlife disease, it can still be tricky to share the necessary information in the right context.

It's also important to resist jumping to conclusions. For example, distemper can cause symptoms that look like rabies. The only way to be sure is to test.

Some of these diseases are potentially fatal. That's something your customer will probably want to know—what's the worst case scenario? But the chance of catching most of these diseases is low, and even then, many of them are treatable.

The trick is to have good, complete, and credible information from a trusted source. One extremely valuable source for current and accurate information is the national Centers for Disease Control (CDC). Most of the pages on their website about wildlife-related health issues are written in simple language and get right to the point. The addresses of the websites that focus on each disease are included at the end of each description.

Other good sources for information about wildlife diseases include physicians; veterinarians; medical entomologists; the state's health, wildlife, and agriculture departments; trade magazines; professional organizations; wildlife conferences; books; fact sheets; videos; listserves; and websites. See the NWCO Resources


Mature raccoon roundworms (Baylisascaris procyonis)

One last medically-related point: When you remove wildlife from people's homes, it's also important to plan for the parasites that may be left behind. Birds and mammals are host to a variety of parasites including fleas, ticks, mites, lice, and bed bugs. Although these parasites generally prefer their original host species, if you remove those animals, the hungry parasites may enter the home looking for a meal. Many of these parasites will bite people and they can be extremely annoying. (And itchy customers are generally not happy, which isn't good for business.)

These pests may fly or crawl into the home through windows, ventilators, cracks, and crevices. Droppings, feathers, fur, food, and carcasses can also attract other pests such as flies and carpet beetles. This can be a significant problem if animals have died in inaccessible locations, such as in the walls. That can happen when an animal is poisoned, and it's one of the risks of using that management method.

Effective clean-up should remove any parasites present in the home. If a site is badly infested, you should wear protective clothing before entering. Even if you don't offer clean-up services, know how to properly advise your clients. Most states have an "integrated pest management" or "IPM" program, usually associated with the land grant university. (In New York, for example, that's Cornell University's "New York State Integrated Pest Management Program.") These programs offer information about how to deal with many pests, including the ones that fall off wildlife. IPM stresses a combination of practical, economical pest management methods that minimize the risks to people and the environment.

Zoonotic Diseases

Now, on to the zoonoses. The zoonotic diseases that are potentially fatal for people are listed first. So, for example, we've listed hantavirus before mange, which a NWCO is far more likely to encounter, because hantavirus can become a much more serious health problem. At the tail end are two wildlife diseases that people generally encounter from contact with a "middleman," either a mosquito or tick.

There's a lot of information in this section. The next chart should help you remember the answers to three critical questions: who? what? how? Who's likely to transmit the disease to people. What disease. And how do people catch it.

How do you protect yourself from wildlife diseases?

Mammal bites or scratches


  • Get rabies pre-exposure vaccine and keep it current
  • Wear animal handling gloves
  • Use a restraining device such as a catchpole
  • Capture animal in trap
  • Avoid contact with animal mouth and saliva
  • Shower soon after work, every day

Mosquito or tick bites


  • Wear loose-fitting, light-colored clothing (harder to bite and makes it easier to see small ticks)
  • Use repellent
  • Tuck pant legs into socks (keeps ticks from crawling onto legs)
  • Check yourself for ticks at lunchtime; remove any you find

Breathe it in

Risks include:

  • Histoplasmosis
  • Hantavirus
  • Canine distemper? (not definitively established)


  • Wear a proper respirator, disposable clothing, goggles, gloves, and hood
  • Ventilate area, if possible
  • Dampen contaminated materials, wipe up with wet sponge
  • Spray contaminated area or dead animals with disinfectant
  • If possible, schedule job for cool, damp weather

Dirty* hands touch mouth, eyes, or nose

Risks include:

  • Raccoon roundworm (mouth)
  • Toxoplasmosis (mouth)
  • Rabies (infected saliva gets into mouth, eyes, or nose)
  • Hantavirus (mouth, eyes, or nose)


  • Wear a proper respirator, disposable clothing, rubber gloves
  • Wash your hands thoroughly with soap and water, especially before eating, drinking, or smoking
  • Avoid contact between your hands and your face. Pay attention when you sneeze, eat, drink, smoke, adjust glasses or put in contacts, or take medication.

Dirty means that the hand, glove, or object is contaminated with whatever causes that disease, such as a virus, bacterium, or a parasite's eggs. These agents are often microscopic.

Disease gets into wound

Risks include:

  • Rabies
  • Hantavirus


  • Protect wounds with bandages, if practical
  • Wear gloves or clothing that covers wound
  • Check wounds and keep them clean

Eat contaminated food or put dirty object into mouth

Risks include:

  • Raccoon roundworm (dirty object)
  • Toxoplasmosis (contaminated meat or dirty object)
  • Hantavirus (may be possible via contaminated food or water)


  • Wash your hands thoroughly after outdoor activities and especially before eating, drinking, or smoking

See advice for customers on pgs. 4-19, 4-20, and 4-24

Handle infected animal or contaminated equipment

Risks include:

  • Mange


  • Wear gloves
  • Minimize contact with mangy animal by using restraining devices
  • Minimize contact with contaminated clothing, equipment
  • Dry clothing at high heat to kill any mites on it

Common Diseases Spread by Nuisance Wildlife

  • Disease: Histoplasmosis
  • Disease: Rabies
  • Disease: Toxoplasmosis
  • Disease: Hantavirus
  • Disease: Mange
  • Disease: Distemper
  • Disease: West Nile Encephalitis
  • Disease: Ancylostomiasis
  • Disease: Aspergillosis
  • Disease: Babesiosis
  • Disease: Botulism
  • Disease: Campylobacteriosis
  • Disease: Cat scratch disease
  • Disease: Cryptococcosis
  • Disease: Cryptosporidiosis
  • Disease: Dermatomycosis
  • Disease: Encephalitis
  • Disease: Ehrlichiosis
  • Disease: Giardiasis
  • Disease: Hantavirus Pulmonary Syndrome
  • Disease: Leptospirosis
  • Disease: Lyme Disease
  • Disease: Lymphocytic-choriomeningitis
  • Disease: Psittacosis
  • Disease: Q (query) fever
  • Disease: Raccoon Roundworm
  • Disease: Rickettsial pox
  • Disease: Salmonellosis
  • Disease: Schistosomiasis
  • Disease: Sporothrichosis
  • Disease: Toxocariasis
  • Disease: Tularemia
  • Disease: Typhus

Disease name

  • Agent (what causes disease)
  • Vectors (animal carriers in the Northeast)
  • Route (how people catch the disease)
  • Symptoms in people

Transmission routes (how people catch disease)

  • Fecal-oral: Person touches contaminant and then, with unwashed hands, touches mouth.
  • Ingestion: Person eats or drinks contaminated product.
  • Inhalation: Person breathes in disease agent.
  • Wound/eye/nose/mouth: The contaminant invades a person's wound, eyes, nose, or mouth.

Next Section Carcass Disposal


Handbook Contents


Needs of People and wildlife

  • Six Questions NWCOs must ask

Federal Laws and Regulations

Safety Risks for Customers

Best Practices for Wildlife Control

Professionalism Resources for NWCOs


This manual was written as a guide to train nuisance wildlife control operators in New York State. Laws and regulations may differ in your state. Always consult local and state laws before implementing wildlife damage management activities.

Contact Information

Contact your local Extension Office


Internet Center for Wildlife Damage Management
National Wildlife Control Operator's Association
Wildlife Control


We thank the New York State Department of Environmental Conservation for contributing this information.

Produced by the NYS Department of Environmental Conservation, Cornell Cooperative Extension, and the NYS Integrated Pest Management Program.

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This work is supported by the USDA National Institute of Food and Agriculture, New Technologies for Ag Extension project.