Original article Prevalence and risk factors of bovine trypanosomosis in Kilwa district, Lindi region of southern Tanzania E.N. Kassian a , M.C. Simuunza b , R.S. Silayo c , L. Moonga d , J. Ndebe b , C. Sugimoto e , B. Namangala d, ⁎ a Department of Livestock and Fisheries Development, Kilwa District Council, P.O. Box 160, Kilwa, Tanzania b Department of Disease Control, School of Veterinary Medicine, University of Zambia, P.O. Box 32379, Lusaka, Zambia c Department of Microbiology and Parasitology, Faculty of Veterinary Medicine, Sokoine University of Agriculture, P.O. Box 3012, Morogoro, Tanzania d Department of Paraclinical Studies, School of Veterinary Medicine, University of Zambia, P.O. Box 32379, Lusaka, Zambia e Research Centre for Zoonosis Control, Hokkaido University, Kita-Ku, Sapporo 001-0020, Japan abstract article info Article history: Received 29 April 2016 Received in revised form 12 March 2017 Accepted 12 March 2017 Available online 14 March 2017 African animal trypanosomosis (AAT) and human African trypanosomosis (HAT) are complex chronic, debilitat- ing, emaciating and often fatal diseases of animals and humans, respectively. This cross-sectional study was con- ducted to determine the prevalence and risk factors associated with bovine trypanosomosis in tsetse-infested Kilwa district, Lindi region, southern Tanzania. Blood samples were collected from 420 cattle randomly selected from 86 herds from ten villages. A maximum of ten herds per village and at most six animals from each herd were selected for sampling. At the same time, a questionnaire was administered. Individual animal samples were analysed using microscopy and pooled sample at herd level were analysed by loop mediated isothermal ampli- fication (LAMP). A herd was considered positive if at least one animal in the herd was positive for AAT. A preva- lence of 9.3% (95% CI: 2.9–14.9) was recorded for AAT by microscopy, mainly caused by Trypanosoma congolense (5.8%, 95% CI = 0.9–10.7), Trypanosoma brucei species (5.8%, 95%, CI = 0.9–10.7) and Trypanosoma vivax (3.5%, 95% CI = 0–7.4). Loop mediated isothermal amplification (LAMP) recorded a heard prevalence of 41.9% (95% CI: 30.0–51.4%), mainly caused by T. congolense (30.2%, 95% CI: 20.5–39.9), T. brucei species (25.6%, 95% CI: 16.4–34.8) and T. vivax (20.9%, 95% CI: 12.3–29.7). Most of the cattle herds had mixed infections of these para- sites. According to LAMP, Miteja and Matandu villages had the highest AAT herd prevalence of 57% (95% CI: 20.3–93.7) while Mavuji had the lowest prevalence of 14% (95% CI: 0–39.7). Data from the present study suggest that district of origin, grazing in game reserve, water source and form of watering point are risk factors associated with AAT in Kilwa district, southern Tanzania. Continuous surveillance and monitoring of AAT using more sensi- tive are recommended. © 2017 Elsevier B.V. All rights reserved. Keywords: AAT Cattle HAT Herd prevalence Kilwa district LAMP Microscopy Tanzania Trypanosomes 1. Introduction African animal trypanosomosis (AAT) or nagana and human African trypanosomosis (HAT) or sleeping sickness are complex chronic, debil- itating, emaciating and often fatal diseases of animals and humans, re- spectively. The outcome of the infection differs substantially among humans, livestock species and within a livestock species and breeds (Connor and Van den Bossche, 2004). The disease is endemic in sub-Sa- haran Africa between latitudes 14°N and 29°S. HAT, transmitted through the bite of an infected tsetse fly, is caused by trypanosomes be- longing to the subgenus Trypanozoon namely Trypanosoma brucei rhodesiense and Trypanosoma brucei gambiense. While T. b. rhodesiense causes the disease in eastern and southern parts of Africa, T. b. gambiense causes HAT in west and central Africa (Brun et al., 2010). HAT is invariably fatal when untreated. Because of the difficult and cost of sur- veillance and treatment, HAT has been considered to have profound im- pact on the socio-economic development of Africa (Mersha et al., 2013). According to Kibona et al. (2002), the disease was first recorded in Tan- zania in 1922 in Maswa district, south of Lake Victoria. It then spread throughout mainland Tanzania such that it is currently endemic in 9 re- gions namely Arusha, Manyara, Mara, Lindi, Ruvuma, Kagera, Tabora, Mbeya and Rukwa. In livestock, AAT is caused by T. congolense, T. vivax, T. brucei brucei, T. evansi, T. simiae, T. suis and T. equiperdum. AAT is one of the most intrac- table diseases affecting most species of livestock in Africa (Zewdu et al., 2013). Infection results in high mortality rate in acute cases and in a se- vere loss of production in chronic cases. The main economic losses at- tributed to AAT are related to cattle mortality and morbidity, diagnosis and treatment costs, the reduction in meat and milk production and the reduction of livestock production areas (Kristjanson et al., 1999). Be- cause of the complexity of the disease-vector inter-relationship, little Veterinary Parasitology: Regional Studies and Reports 9 (2017) 1–5 ⁎ Corresponding author. E-mail address: b.namangala@unza.zm (B. Namangala). http://dx.doi.org/10.1016/j.vprsr.2017.03.004 2405-9390/© 2017 Elsevier B.V. All rights reserved. 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