Rodents and Shrews as Vectors of Zoonotic Spirochetes and Trypanosomes in Tanzania

Abstract

Clinically healthy wild rodents and shrews (Crocidura spp.) were captured from different localities in Morogoro, Tanga, Dodoma, Singida, Mbeya, Kilimanjaro and Mtwara regions of Tanzania. Blood samples were collected from the captured animals and screened for infectious agents of public health importance, including; Trypanosoma spp., Plasmodium spp., Borrelia spp. and Bacillus spp. Out of 4,963 blood smears examined, 424 (8.5%) were from shrews and 4,539 (91.5%) were from rodents. Trypanosoma spp. were demonstrated in 198 (3.9%) and 7 (0.1%) blood smears of rodents and shrews, respectively. Borrelia spp. were  demonstrated in 6 (0.2%) and 5 (1.2%) rodents and shrews, respectively. Bacillus spp. were found in 149 (3.6%) and 27 (6.4%) rodents and shrews respectively. Mastomys natalensis, Rattus rattus and Crocidura spp. were found to host all of the five haemoparasites detected. The public health significance of this study is notable from the fact that haemoparasites that were demonstrated in apparently healthy rodents are potential human pathogens.

Key words: Rodent, shrew, Crocidura spp., haemoparasite, spirochete