Dynamic shifts in the epidemiology and transmission of murine typhus are not unprecedented. Although the rat-to-rat cycle of transmission by fleas is often referred to as an urban cycle, the rural South experienced high rates of murine typhus in the 1940s as a result of a proliferation of rats after a change in crop production from cotton to peanuts, because rats were attracted to the peanuts as a source of food (13). In southern California, opossums infested with R. typhi– and R. felis–infected cat fleas (C. felis) have been associated with a shift of fleaborne rickettsioses from the urban center of Los Angles to suburban areas (14). This suburban cycle of transmission involving C. felis plays a recognized role in Corpus Christi, Texas, a coastal city ≈220 miles southwest of Galveston (1). Additionally, this cycle has been suspected in a recent outbreak of murine typhus in the central Texas city of Austin (15).The recent recognition of murine typhus in Galveston may reflect the reemergence of R. typhi in rats; it may also reflect a cycle involving opossums and cats. Additionally, R. felis may play a role as a serologically cross-reacting culprit of illness. Further study is required to better understand the ecology and epidemiology of murine typhus as it reemerges in Galveston. Physicians and public health officials should be aware of this reemerging threat. Furthermore, vector control is of utmost importance.
Categories: Infectious Diseases