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Zoonotic Disease: When Humans and Animals Intersect

Zoonotic Disease: When Humans and Animals Intersect [PDF - 780KB]

What are zoonotic diseases?

Zoonotic diseases are contagious diseases spread between animals and humans. These diseases are caused by bacteria, viruses, parasites, and fungi that are carried by animals and insects. Examples are anthrax, dengue, Ebola hemorrhagic fever, Escherichia coli infection, Lyme disease, malaria, Plague, Rocky Mountain spotted fever, salmonellosis, and West Nile virus infection.

Photograph of scores of chickens in a building.

How do you get zoonotic diseases?

People can get zoonotic diseases from contact with infected live poultry, rodents, reptiles, amphibians, insects, and other domestic and wild animals. A common way for these diseases to spread is through the bite of a mosquito or tick. People can get diseases in most places where they might have contact with infected animals and insects, including:

Animal displays
Petting zoos
Pet stores
Nature parks

Wooded and bushy areas
Farms
County or state fairs
Child–care facilities or schools

Who can get zoonotic diseases?

Anyone who has contact with animals can get a zoonotic disease, but people may be more at risk than others. These include people with a weakened immune system, children age 5, the elderly, and pregnant women.

How to prevent zoonotic diseases

Be aware of zoonotic diseases and your potential for infection
Wash hands thoroughly and frequently
Avoid direct contact with certain animals and their environment
Closely supervise children to ensure they wash their hands properly and avoid hand–to–mouth activities (thumb–sucking, eating, and use of pacifiers) after animal contact
Use EPA–registered insect repellents that contain 20% or more DEET (N, N–diethyl–m–toluamide) on the exposed skin for protection that lasts up to several hours
Use products that contain repellents (such as permethrin) on clothing. Treat clothing and gear, such as boots, pants, socks and tents
Look for and remove ticks from your body. Parents should check their children for ticks
Limit the number of places around your home for mosquitoes to breed by getting rid of items that hold water

Interesting facts about zoonotic diseases

About 75% of recently emerging infectious diseases affecting humans are diseases of animal origin, and approximately 60% of all human pathogens are zoonotic.
Tick–borne diseases, including Lyme disease and Rocky Mountain spotted fever, are serious public health problems, infecting tens of thousands in the United States each year. CDC is working closely with local communities, developing innovative control approaches and researching improved diagnostics.
Almost all persons infected by rabid animals will die if not treated appropriately. Dogs are responsible for most human rabies deaths worldwide, but the public health threat of canine rabies has been virtually eliminated in the United States.
There have been 1.5 million West Nile virus infections since 1999. 2.5 billion people are at risk for dengue in more than 100 endemic countries with 50 million cases of dengue fever each year.