Frequently Asked Questions About Zoonosis

According to the Centers for Disease Control and Prevention (CDC), zoonotic diseases are prevalent. Scientists estimate that six out of every ten known infectious diseases in people come from animals. All types of animals are carriers of zoonotic diseases.  From mosquitoes and ticks— which carry some of the more serious disease— to household pets such as cats and dogs.

People are constantly in contact with animals and insects. According to the CDC, the most common ways in which zoonotic diseases spread are:

• Direct contact. A zoonotic disease can spread to a person if he or she comes in direct contact with the saliva, blood, urine, mucous, feces, or any other bodily fluid of an infected animal. It can spread by merely petting an animal which carries a disease.
• Indirect contact. Sometimes a zoonotic disease can move through surfaces or objects that the infected animal has come into contact with. The germs may be in a fish tank, a chicken coup, or the soil or plants in the animal’s habitat.
• Vector-borne. Diseases can easily move through bites or stings of an infected insect or animal.
• Foodborne. It is not uncommon to get food poisoning from contaminated animal foods, like raw dairy products, or undercooked meat or eggs. Even fruits and vegetables can be contaminated if they are not washed well.

Many different diseases can be spread from an animal to a person. Some are life-threatening, and some are not. The most dangerous conditions tend to spread through insect bites, like from mosquitos or ticks. Many zoonoses are treatable or will resolve within a few days or weeks—like food poisoning for example. Others, however, may cause lifelong or fatal conditions. If you think you may have been affected by a zoonotic disease, call your doctor right away.

Zoonoses can be caused by a virus, bacteria, fungus, or a parasite. Some examples of zoonotic diseases include:

• Animal flu
• Anthrax
• Bird flu
• Cat-scratch disease
• E. Coli infections
• Ebola
• Lyme disease
• Malaria
• Rabies
• Ringworm
• Salmonella
• Swine Influenza
• West Nile virus
• Zika fever

Anyone can be at risk for zoonoses, even healthy individuals. People who should take extra precaution include:

• Children under the age of five
• Adults over the age of 65
• People with compromised immune systems
• Pregnant women

Zoonotic diseases exist in every part of the world. However, in certain parts of the world, specific dangerous zoonoses are more prevalent than in others. People living in or traveling to areas in which specific zoonotic diseases are prevalent should take extra precautions. Methods such as applying insect repellent, wearing long pants and long-sleeved shirts, and vaccination. For example, Lyme disease spreads exclusively through deer ticks found in North America. Malaria spreads through mosquitoes in countries across Asia, Africa, and South America. Zoonoses can also be spread in petting zoos, at fairs, schools, and parks. It is important to maintain proper hygiene by washing hands with clean, running water and soap after coming into contact with animals. When cooking meat, fish, or poultry, or eggs wash them thoroughly before cooking. And make sure they are fully cooked before eating.

The type of zoonotic disease a person has and the general health of the person involved are two important determining factors when considering outlook. Treatment for a pregnant woman who has contracted a zoonotic disease will involve consideration of both the pregnant woman and her unborn child. Since the establishment of hygiene regulations 100 years ago, the United States and other developed countries have taken great strides in reducing the incidence of fatal zoonoses such as bovine tuberculosis, bubonic plague, and glanders, which were responsible for millions of deaths in the past. The World Health Organization (WHO) is always working on prevention and reducing the transmission of zoonoses.