SURVEY OF THE SEROPREVALENCE OF BARTONELLA-QUINTANA IN HOMELESS PEOPLE

Trench fever is caused by Bartonella (Rochalimaea) quintana, a small g ram-negative rod that is transmitted by body lice, Recently, B. quinta na infections in homeless patients have been reported in the United St ates and Europe, From October 1993 to October 1994, the seroprevalence of antibodies to B. quintana was assessed by indirect immunofluoresce nce in a prospective study of 221 nonhospitalized homeless people, 43 hospitalized homeless patients (cases), 250 blood donors, and 57 hospi talized matched controls, Four (1.8%) of 221 nonhospitalized homeless people tested had titers of >1:100. Of the 43 cases, seven (16%) had s erological titers of greater than or equal to 1:100. None of the 250 s erum samples from blood donors contained antibodies to B. quintana. Th e presence of antibodies to B. quintana in cases was significantly ass ociated with the presence of body lice, exposure to cats, headaches, e astern European origin, and pain in the legs, This study demonstrates the presence of antibodies to B. quintana in the homeless population a nd should alert physicians that B. quintana might be an etiologic agen t of fever in homeless patients.