logoPROFESSIONAL VERSION

Treatment of Zoonoses

Reviewed/Revised Feb 2023

The treatment of zoonotic and nonzoonotic diseases of animals is similar; however, treatments that prolong the shedding of zoonotic organisms should be avoided unless there are overriding considerations. For example, antimicrobial treatment is usually contraindicated in uncomplicated Salmonella-associated diarrhea because these drugs may prolong shedding of this organism. Conversely, animals that carry zoonotic organisms may sometimes be treated to decrease human exposure, even when the infection is subclinical or expected to be self-limiting, such as a minor skin lesion due to dermatophytosis.

During treatment of zoonotic diseases, every precaution should be taken to prevent infection in humans. Professional judgment is required to determine whether to keep the animal in its home environment or isolate it in a hospital ward. Factors to consider include the potential severity of the disease in humans, the susceptibility of individuals in the household, and the ability of human caregivers to effectively perform barrier nursing, sanitation, and hygiene protocols. The owner should be informed if treatment is not certain to eliminate the pathogen, which could then persist in a latent or chronic, subclinical form. Zoonotic concerns may dictate euthanasia of the animal, especially when the disease is likely to be fatal.

Humans who may have contracted a zoonotic disease should be referred to a physician for diagnosis and treatment. The physician should be given any information necessary to facilitate diagnosis, particularly if the disease is unusual and would not ordinarily be among the differential diagnoses. Simultaneous elimination of the pathogen from both animal and human hosts is ideal, to prevent it from cycling between the hosts. Certain zoonotic diseases (eg, rabies) must be reported to public health authorities.

Key Points

  • Potential effects on both humans and animals should be considered when deciding how (and whether) to treat a zoonotic disease.

  • Precautions should be taken to decrease the risk of exposure for humans during treatment.

  • Humans who may have contracted a zoonotic disease should be referred to a physician, who should be given any information necessary to facilitate the diagnosis.

  • Some zoonotic diseases that occur in animals must be reported to the public health department.

For More Information

  • Also see pet health content regarding zoonoses.

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