Mediterranean spotted fever in travelers from the United States

Abstract

Background: We wish to increase awareness by U.S. physicians of the clinical manifestations and diagnosis of Mediterranean spotted fever (MSF), and to determine the incidence of MSF among travelers returning to the United States from endemic areas. Methods: We report a case of a 56-year-old female physician from New Orleans who returned from a 3-week safari trip to Zimbabwe and Zambia with clinical findings of MSF. The diagnosis was confirmed with a greater than fourfold rise in titer of IgM and IgG antibody to Rickettsia conorii on acute and convalescent sera (16 days apart) using indirect immunofluorescence technique. In addition, we conducted a MEDLINE computer search of published MSF cases in U.S. travelers returning to the United States and obtained the United States data over the past 20 years from the Centers for Disease Control and Prevention (CDC). Results: Less than 50 imported cases of MSF have been reported and confirmed by the CDC. Only seven cases have been published in the literature and none in the last 7 years. Conclusions: Despite the increasing incidence of MSF in Europe, Asia and Africa, and the high number of U.S. citizens traveling to these endemic areas, only a few imported cases of MSF in travelers have been reported in the United States. Physicians in the United States are not familiar with the clinical findings and diagnosis of MSF; therefore this disease is underrecognized in the majority of cases.