Zoonotic Diseases (Animal to Human)

Zoonotic diseases are caused by germs spread between animals and people. An estimated 6 out of every 10 known infectious diseases in people can be spread from animals. You can protect yourself from zoonotic diseases by washing your hands.

(Adapted from CDC)

Many people interact with animals in their daily lives, both at home and away from home. However, animals can sometimes carry harmful germs that can spread to people and cause illness – these are known as zoonotic diseases or zoonoses. Scientists estimate that more than 6 out of every 10 known infectious diseases in people can be spread from animals, and 3 out of every 4 new or emerging infectious diseases in people come from animals.

Animals provide food, fiber, livelihoods, travel, sport, friendship, and education for people across the globe. Millions of households in the U.S. have one or more pets. We might come into contact with animals in either urban (city) or rural settings, during travel, while visiting animal exhibits, or while enjoying outdoor activities.

Zoonotic diseases are caused by harmful germs like viruses, bacteria, parasites, and fungi. These germs can cause many different types of illnesses in people and animals, ranging from mild to serious illness and even death.

Animals can sometimes appear healthy even when they are carrying germs that can make people sick, based on the zoonotic disease.

How do germs spread between animals and people?

Because of the close tie between people and animals, it’s important to be aware of the common ways people can get the germs that can cause zoonotic diseases. These can include:

  • Direct contact: Coming into contact with the saliva, blood, urine, mucous (snot), feces (poop), or other body fluids of an animal with the disease. Examples can include petting or touching animals, and bites or scratches.
  • Indirect contact: Coming into contact with areas where animals live and roam, or objects or surfaces that have been tainted with germs. Examples can include aquarium tank water, pet living areas, chicken coops, barns, plants, and soil, as well as pet food and water dishes.
  • Vector-borne: Being bitten by a tick, or an insect like a mosquito or a flea.
  • Foodborne: Each year, 1 in 6 Americans get sick from eating impure food. Eating or drinking something unsafe, such as unpasteurized (raw) milk, undercooked meat or eggs, or raw fruits and vegetables that are tainted with feces from an animal with the disease. Impure food can cause illness in people and animals, including pets.
  • Waterborne: Drinking or coming in contact with water that has been tainted with feces from an animal with the disease.

Who is at a higher risk of serious illness from zoonotic diseases?

Anyone can get sick from a zoonotic disease, including healthy people. However, some people are more likely than others to get really sick, and even die, from infection with certain diseases. These groups of people include:

  • Children younger than 5,
  • Adults older than 65,
  • People with weakened immune systems, and
  • People who are pregnant.

What can you do to protect yourself and your family from zoonotic diseases?

People can come in contact with animals in many places. This includes at home and away from home, in places like petting zoos, fairs, schools, stores, and parks. Insects, like mosquitoes, fleas and ticks bite people and animals, day and night. Thankfully, there are things you can do to protect yourself and your family from zoonotic diseases.

  • Keep hands clean. Washing your hands right after being around animals, even if you didn’t touch any animals, is one of the most important steps you can take to avoid getting sick and spreading germs to others.
    • Many germs are spread by not washing hands properly with soap and clean, running water.
    • If soap and water are not readily available, you can use an alcohol-based hand sanitizer that contains at least 60% alcohol.
    • Because hand sanitizers do not get rid of all types of germs, it is important to wash your hands with soap and water if they are available.
  • Know the simple things you can do to stay safe around your pets and other animals.
    • Avoid bites.
  • Prevent bites from mosquitoes, ticks, and fleas.
  • Learn more about ways to handle food safely—whether it’s for yourself or your family, your pet, or other animals.
  • Be aware of zoonotic diseases both at home, away from home (such as at petting zoos or other animal exhibits), in childcare settings or schools and when you travel.