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Zoonotic diseases

Last updated: May 5, 2021

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Zoonotic diseases are infections that are transmitted from animals to humans. While animals may transmit infection directly, they usually serve as hosts for a pathogen that is then transmitted to humans by a vector (e.g., ticks, fleas). Zoonoses are usually endemic to certain geographical regions, and peaks in incidence often correlate with the life cycle of the transmitting vector. Common diseases include Q fever, Rocky Mountain spotted fever, endemic typhus, ehrlichiosis, and babesiosis. Although these conditions differ in their exact presentation, symptomatic cases typically present with fever, flulike symptoms, and possibly skin rashes. In some cases of fulminant disease, there may be complications such as disseminated intravascular coagulation, shock, and organ failure. Most zoonoses are treated with antibiotics and respond well to treatment.

For information on some other zoonotic diseases such as anaplasmosis and epidemic typhus, see “Tick-borne diseases” and “Louse-borne diseases.”

Type of Q fever
Acute Q fever Chronic Q fever
Incubation period [3]
  • 2–6 weeks
  • Months to years
Clinical features
Diagnostics Serology via IFA (best initial test)
Additional findings
  • Avoid consuming unpasteurized milk products

The Rash of Rocky Mountain spotted fever starts at the wRists.

Palms and soles are crucial for driving CARSS:” the typical infectious causes of a rash of palms and soles include Coxsackie A infection, RMSF, and Secondary Syphilis.

Endemic typhus (also known as murine typhus)

The rash of Typhus starts on the Trunk.

Scrub typhus

ANother GRANd day starts with an EaRLI CoFFEE in the MOrNing:” in ANaplasmosis, morulae are formed in GRANulocytes and ehrlichiosis is caused by EhRLIchia CHaFFEEnsis in MONocytes.

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