Survey of three bacterial louse-associated diseases among rural Andean communities in Peru: Prevalence of epidemic typhus, trench fever, and relapsing fever

Typhus and other louse-transmitted bacterial infections in Peruvian sierra communities are known to occur but have not recently been assessed. In this study, 194 of 1,280 inhabitants of four villages in Calca Province in the Urubamba Valley were included. Thirty-nine (20%) of the 194 volunteers had antibodies to Rickettsia prowazekii, whereas 24 (12%) had antibodies to Bar tonella quintana and 2 against Borrelia recurrentis. There was a significan t correlation between the presence of infesting ectoparasites and antibodie s to R. prowazekii, as well as between antibodies to R. prowazekii and ecto parasite infestation and fever in the previous 6 months. The proportion of inhabitants infested with ectoparasites was significantly higher in the hig hest-altitude village than in the other three villages. Two volunteers' ant ibody levels suggested a recent typhus infection, but only B. quintana DNA was amplified from lice. Epidemic typhus remains extant in the area, and B. quintana infections were encountered and documented for the first time in South America.