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Updated: Jul 7, 2026
10:17
Cities As Interfaces of Zoonotic Hazard Emergence: Development of the New York City Tick and Wildlife Urban Surveillance System
Published on: March 10, 2026
Murine typhus: an unrecognized suburban vectorborne disease
1Acute Communicable Disease Control Program, Los Angeles County Public Health Department, Los Angeles, California 90012, USA. rciven@ph.lacounty.gov
Summary
Murine typhus, a flea-borne illness caused by Rickettsia typhi, commonly affects urban and suburban areas. In the US, cats and opossums are key reservoirs, with cat fleas as the main vector.
Area of Science:
- Infectious Diseases
- Medical Entomology
- Zoonotic Diseases
Background:
- Murine typhus is an acute febrile illness caused by Rickettsia typhi, found globally.
- It is typically transmitted by rodent fleas in urban and port settings with high rat populations.
- In the United States, cases are prevalent in Texas and California, with unique reservoirs and vectors.
Purpose of the Study:
- To describe the epidemiology and clinical presentation of murine typhus.
- To identify the primary reservoirs and vectors of Rickettsia typhi in the United States.
- To outline diagnostic and treatment strategies for murine typhus.
Main Methods:
- Review of epidemiological data on murine typhus cases.
- Identification of Rickettsia typhi reservoirs and vectors.
- Clinical case descriptions including symptoms and diagnostic methods.
- Evaluation of treatment efficacy with doxycycline.
Main Results:
- Rickettsia typhi is distributed worldwide, with US cases concentrated in Texas and California.
- Opossums and cats, not just rodents, serve as important reservoirs in the US.
- The cat flea (Ctenocephalides felis) is the principal vector.
- Common symptoms include fever, rash, and headache; diagnosis is via serology.
- Doxycycline is effective in shortening illness duration.
Conclusions:
- Murine typhus epidemiology varies geographically, with distinct reservoirs and vectors in the US.
- Prompt diagnosis using serologic testing and treatment with doxycycline are crucial.
- Understanding local transmission cycles is vital for public health interventions.
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