Acta Tropica 171 (2017) 151–158
journal homepage: www.elsevier.com/locate/actatropica

Rodent-borne Trypanosoma from cities and villages of Niger and Nigeria: A special role for the invasive genus Rattus?

C. Tatard¹, M. Garb^1,2, P. Gauthier³, K. Hima⁴, E. Artige¹, D.K.H.J. Dossou⁵, S. Gagaré⁶, G. Genson¹, P. Truc⁷, G. Dobigny³*

¹Institut National de Recherche Agronomique, Centre de Biologie pour la Gestion des Populations (CBGP), Campus International de Baillarguet, CS30016, 34988 Montferrier-sur-Lez, France
²Direction Générale de la Protection des Végétaux, Ministère de l’Agriculture et de l’Elevage, BP 323, Niamey, Niger
³Institut de Recherche pour le Développement (IRD), CBGP, France
⁴Université Abdou Moumouni, Faculté des Sciences, Département de Biologie Animale, BP 10662, Niamey, Niger
⁵Université d’Abomey-Calavi, Ecole Polytechnique d’Abomey-Calavi, Laboratoire de Recherche en Biologie Appliquée, 01BP2009, Cotonou, Benin
⁶Centre Régional Agrhymet, Département Formation Recherche, BP11011, Niamey, Niger
⁷Institut de Recherche pour le Développement (IRD), UMR IRD/CIRAD InterTryp 177, Campus International de Baillarguet, 34398 Montferrier-sur-Lez Cedex 5, France

Abstract. Although they are known to sometimes infect humans, atypical trypanosomes are very poorly documented, especially in Africa where one lethal case has yet been described. Here we conducted a survey of rodent-borne Trypanosoma in 19 towns and villages of Niger and Nigeria, with a special emphasis on Niamey, the capital city of Niger. The 1298 rodents that were captured yielded 189 qPCR-positive animals from 14 localities, thus corresponding to a 14.6% overall prevalence. Rats, especially black rats, displayed particularly elevated prevalence (27.4%), with some well sampled sites showing 40–50% and up to 68.8% of Trypanosoma-carrying individuals. Rattus were also characterized by significantly lower Ct values than in the other non-Rattus species. DNA sequences could be obtained for 43 rodent-borne Trypanosoma and corresponded to 41 T. lewisi (all from Rattus) and 2 T. microti (from Cricetomys gambianus). These results, together with data compiled from the available literature, suggest that Rattus may play a particular role for the maintaining and circulation of Trypanosoma, especially T. lewisi, in Africa. Taken into account its strong abilities to invade coastal and inland regions of the continent, we believe that this genus deserves a particular attention in regards to potentially under-looked but emerging atypical trypanosome-related diseases.

Keywords. zoonotic agents, Trypanosoma lewisi, biological invasion, commensal rodents, Africa

*Corresponding author: gauthier.dobigny@ird.f (G. Dobigny).