Looking for Tropheryma whipplei source and reservoir in rural Senegal.

Tropheryma whipplei, the bacterium linked to Whipple's disease, is involved in acute infections and asymptomatic carriage. In rural Senegal, the prevalence of T. whipplei is generally high but is not homogeneous throughout households in the same village. We studied environmental samples collected in two Senegalese villages and conducted the survey to investigate the difference between households. Overall, the comparison between five households with very high T. whipplei prevalence and three households without any registered cases showed that the only difference was the presence of toilets in the latter (1/5 versus 3/3; P = 0.01423). Among the 1,002 environmental specimens (including domestic and synanthropic animals and dust sampled in households) tested for T. whipplei DNA, only four specimens were slightly positive. Humans are currently the predominant identified reservoir and source of T. whipplei in these populations. Limited access to toilets and exposure to human feces facilitate the fecal-oral transmission of T. whipplei.