High Seroprevalence for Typhus Group Rickettsiae, Southwestern Tanzania

Tatjana Dill,Thomas Löscher,Elmar Saathoff,Petra Clowes,Michael Hoelscher,Inge Kroidl,Elias Ntinginya,Norbert Heinrich,Harun Machibya,Gerhard Dobler,Leonard Maboko

doi:10.3201/eid1902.120601

Abstract

Rickettsioses caused by typhus group rickettsiae have been reported in various African regions. We conducted a cross-sectional survey of 1,227 participants from 9 different sites in the Mbeya region, Tanzania; overall seroprevalence of typhus group rickettsiae was 9.3%. Risk factors identified in multivariable analysis included low vegetation density and highway proximity.

Highlights

Rickettsioses caused by typhus group rickettsiae have been reported in various African regions
Assume that the antibodies detected in Tanzania in this study were caused by R. typhi, because, to our knowledge, no severe or epidemic illness compatible with louse-borne typhus has been described in the study region
Murine typhus is found throughout the world, widely distributed in subtropical and tropical regions, and is most apparent in port cities with large rat populations [2,4], which provide a reservoir for the pathogen and its main vector, the rat flea (Xenopsylla cheopsis)

Summary

High Seroprevalence for Typhus Group

We conducted a cross-sectional survey of 1,227 participants from 9 different sites in the Mbeya region, Tanzania; overall seroprevalence of typhus group rickettsiae was 9.3%. The Study We conducted a cross-sectional seroprevalence study among 1,227 persons from the Mbeya region in southwestern Tanzania to estimate TGR seroprevalence rates and to assess associated sociodemographic and environmental risk factors. To identify possible risk factors for TGR IgG positivity, we analyzed seropositivity as the binary outcome of uniand multivariable Poisson regression models with robust variance estimates adjusted for household clustering. Several environmental covariates showed a significant inverse association with TGR IgG (Table), which included vegetation density, rainfall, minimum and night temperatures, whereas population density, cattle density, and socioeconomic status were positively associated with seropositivity. Other factors, including sex, livestock ownership, day and night average land surface temperatures, and other environmental factors, were unrelated to TGR seropositivity

Conclusions

No information

We thank the study participants as well as Wolfram