Human ehrlichiosis--Maryland, 1994

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    MMWR. Morbidity and Mortality Weekly Report
    |September 20, 1996
    PubMed

    Insights

    Human monocytic ehrlichiosis (HME), a tickborne illness, was confirmed in five Maryland residents near the Chesapeake Bay. This highlights the emerging threat of Ehrlichia chaffeensis infection in new geographic regions.

    Area of Science:

    • Infectious Diseases
    • Tickborne Illnesses
    • Microbiology

    Background:

    • Ehrlichiosis is an emerging infectious disease caused by rickettsia bacteria that infect white blood cells.
    • Human monocytic ehrlichiosis (HME) is caused by Ehrlichia chaffeensis, transmitted by the Lone Star tick.
    • Historically, HME cases are concentrated in southeastern and south-central United States.

    Observation:

    • Five cases of confirmed HME were identified in Maryland residents between May and July 1994.
    • All affected individuals resided near the Chesapeake Bay.
    • Each case reported a history of tick exposure prior to illness.

    Findings:

    • Serological testing confirmed HME in the five Maryland residents.
    • The cases represent a geographic expansion of identified HME infections.
    • Clinical and epidemiological data were collected and analyzed.

    Implications:

    • This finding suggests that Ehrlichia chaffeensis may be spreading to new areas.
    • Increased awareness of HME is needed in regions near the Chesapeake Bay.
    • Further surveillance for tickborne diseases in Maryland is warranted.

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