The identification of murine typhus in Galveston, Texas, may signal the re-emergence of the disease in this port city, according to researchers from the University of Texas Medical Branch.
The researchers evaluated 18 adult patients aged 18 years and older who had presented with febrile illness to the University of Texas Medical Branch in Galveston between February and December 2013. Blood samples were tested for murine typhus using real-time PCR, shell vial culture and immunofluorescence assay.
Ten of the patients prospectively enrolled in the study had murine typhus (seven confirmed cases and three probable). An additional two probable cases were identified from retrospective serum samples. One patient, an alcoholic male aged 48 years, was confirmed by isolation of Rickettsia typhi from blood. In addition to fever, patients reported headache (100%), chills (58%), myalgias (50%) and rashes (50%). Elevated hepatic transaminases were seen in nine (75%) patients, seven (58%) were hospitalized, and two (17%) were admitted to the ICU. With the exception of one of the retrospectively identified patients, all were treated empirically for murine typhus with either doxycycline or minocycline. All patients recovered with no differences between treatments.
According to the researchers, the disease was endemic to Galveston until the introduction of dichlorodiphenyltrichloroethane, or DDT, in 1946 as a means of controlling rat ectoparasites.
“The recent recognition of murine typhus in Galveston may reflect the re-emergence of R. typhi in rats; it may also reflect a cycle involving opossums and cats,” they wrote. “Additionally, R. felis may play a role as a serologically cross-reacting culprit of illness. Physicians and public health officials should be aware of this re-emerging threat. Furthermore, vector control is of utmost importance.”
Disclosure: The researchers report no relevant financial disclosures.