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Professional Version

Zoonotic Diseases


Anna Rovid Spickler

, DVM, PhD, Center for Food Security & Public Health, College of Veterinary Medicine, Iowa State University

Medically Reviewed May 2015 | Modified Nov 2022
Topic Resources

for a list of zoonotic bacterial, viral, fungal, and parasitic diseases, grouped by category. Many proven zoonoses, including some diseases that are rare in people, organisms that are maintained primarily in people, some primate diseases, and diseases caused by fish and reptile toxins have been omitted. The table is intended to give a general clinical picture of each disease; current medical texts or review articles should be consulted for a more complete description. Clinical signs are listed; asymptomatic infections can also be assumed to occur in most cases. An indication of the mortality rate among healthy individuals has been provided for many infections. However, there is almost always a chance of death whenever lesions can become generalized, vital organs may be affected, secondary infections occur, and/or the patient is immunosuppressed. The mortality rate is often influenced by the availability of medical care, and it is generally lower when advanced medical support is available. The risk of death from some bacterial diseases with high mortality rates can be nearly eliminated with prompt antibiotic treatment.

If a disease is known to have unusual manifestations or to be particularly common and/or severe in immunocompromised people, this has been noted. In addition to these diseases, many pathogens can cause more severe disease and/or unusual signs in immunocompromised patients. Information on the geographic range of an organism should be taken as a rough guide. The precise ranges of many pathogens have not been completely determined. Organisms may also expand their range or be eradicated from areas where they were once abundant. In this table, “worldwide” indicates those organisms that are widespread and found on all major continents, although they may absent from some areas (eg, polar regions or some islands). In some cases, organisms indicated as being present on a continent may nevertheless have a limited distribution.

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