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Volume 26, Number 6—June 2020

Multihost Transmission of Schistosoma mansoni in Senegal, 2015–2018

Stefano Catalano1, Elsa Léger1Comments to Author , Cheikh B. Fall, Anna Borlase, Samba D. Diop, Duncan Berger, Bonnie L. Webster, Babacar Faye, Nicolas D. Diouf, David Rollinson, Mariama Sène, Khalilou Bâ, and Joanne P. Webster
Author affiliations: Royal Veterinary College, University of London, Hatfield, UK (S. Catalano, E. Léger, A. Borlase, J.P. Webster); Université Cheikh Anta Diop, Dakar, Senegal (C.B. Fall, B. Faye); Big Data Institute, University of Oxford, Oxford, UK (A. Borlase); Université Alioune Diop de Bambey, Bambey, Senegal (S.D. Diop); Wellcome Sanger Institute, Hinxton, UK (D. Berger); Natural History Museum, London, UK (B.L. Webster, D. Rollinson); Université Gaston Berger, Saint-Louis, Senegal (N.D. Diouf, M. Sène); Institut de Recherche pour le Développement, Dakar (K. Bâ)

Main Article

Table 1

Schistosoma mansoni infection rate and intensity by host and study site, Senegal, 2015–2018*

Study site Mastomys huberti mice
Arvicanthis niloticus rats
School-aged children
Biomphalaria pfeifferi, snails, no. infected/ total no. (%)
No. infected/ total no. (%) Median (range) infection intensity No. infected/ total no. (%) Median (range) infection intensity No. infected/ total no. (%) Median (range) infection intensity
Didjiery† 0/12 NA 0/69 NA 6/17 (35.3) 180 (12–408) 0/111
Ganket 2/4 (50.0) 18.5 (5–32) 0/4 NA NA NA NA
Gueo 10/19 (52.6) 14 (2–64) NA NA NA NA NA
Keur Momar Sarr 1/19 (5.3) 2 NA NA NA NA NA
Mbane† 0/60 NA 0/34 NA 1/26 (3.8) 264 1/55 (1.8)
Merina Guewel 1/12 (8.3) 2 NA NA 6/16 (37.5) 42 (12–108) NA
Nder† 1/60 (1.7) 2 0/11 NA 5/44 (11.4) 12 (12–24) 6/84 (7.1)
Ndombo NA NA NA NA 5/101 (5.0) 12 (12–24) 0/5
Richard Toll† 0/10 NA 1/73 (1.4) 4 13/29 (44.8) 180 (24–1,656) 0/4
Temeye† 8/43 (18.6) 4 (2–35) 0/4 NA 1/21 (8.3) 12 2/75 (2.7)
Thiago† 0/4 NA NA NA NA NA 0/2

*Only study sites where infected hosts were detected are included. Infection intensities were calculated by using eggs per gram of fecal samples for school-aged children and number of adult worms in rodents (M. huberti and A. niloticus). Infection intensity was not quantified for B. pfeifferi snails (intermediate host). NA, not applicable.
†For rodents, values include data previously reported (21).

Main Article

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1These first authors contributed equally to this article.

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