Serologic evidence of respiratory and rickettsial infections among Somali refugees

Somali refugees living in a camp located in Djibouti were studied in October 1991 and May 1992. The refugees had been living at the camp for about two years. The median age of volunteers was 25 years, of whom 69% were female. Paired sera obtained seven months apart were evaluated by complement fixation, microimmunofluorescence, indirect fluorescent antibody, streptococcal antibody, and enzyme-linked immunosorbent assay techniques for evidence of pathogen infection. Fifty-two percent, 31.3%, 8.0%, 5.9%, and 25.4% of the volunteers had serologic evidence for pre-enrollment infection with Chlamydia pneumoniae, Mycoplasma pneumoniae, Rickettsia typhi, R. conorii, and Coxiella burnetti, respectively. Similarly, 43.5%, 5.2%, 6.1%, 10.7%, 15.8%, and 11.9% of the volunteers studied had serologic evidence for new infection with Streptococcus pyogenes, C. pneumoniae, M. pneumoniae, R. typhi, R. conorii, and Cox. burnetii, respectively. These data suggest that the studied pathogens may be endemic in displaced populations living in the Horn of Africa.