Domestic pigs as potential reservoirs of human and animal trypanosomiasis in Northern Tanzania

Abstract

BackgroundPig keeping is becoming increasingly common across sub-Saharan Africa. Domestic pigs from the Arusha region of northern Tanzania were screened for trypanosomes using PCR-based methods to examine the role of pigs as a reservoir of human and animal trypanosomiasis.MethodsA total of 168 blood samples were obtained from domestic pigs opportunistically sampled across four districts in Tanzania (Babati, Mbulu, Arumeru and Dodoma) during December 2004. A suite of PCR-based methods was used to identify the species and sub-species of trypanosomes including: Internally Transcribed Sequence to identify multiple species; species specific PCR to identify T. brucei s. l. and T. godfreyi and a multiplex PCR reaction to distinguish T. b. rhodesiense from T. brucei s. l.ResultsOf the 168 domestic pigs screened for animal and human infective trypanosome DNA, 28 (16.7%) were infected with one or more species of trypanosome; these included: six pigs infected with Trypanosoma vivax (3.6%); three with Trypanosoma simiae (1.8%); two with Trypanosoma congolense (Forest) (1%) and four with Trypanosoma godfreyi (2.4%). Nineteen pigs were infected with Trypanosoma brucei s. l. (10.1%) of which eight were identified as carrying the human infective sub-species Trypanosoma brucei rhodesiense (4.8%).ConclusionThese results show that in Tanzania domestic pigs may act as a significant reservoir for animal trypanosomiasis including the cattle pathogens T. vivax and T. congolense, the pig pathogen T. simiae, and provide a significant reservoir for T. b. rhodesiense, the causative agent of acute Rhodesian sleeping sickness.

Evidence of the absence of human African trypanosomiasis in two northern districts of Uganda: Analyses of cattle, pigs and tsetse flies for the presence of Trypanosoma brucei gambiense

“…However, cases of T. b. brucei were found in both animal populations with pigs proving to have the higher prevalence of T. b. brucei infection. This is typical of trypanosome epidemiology which has been shown to be highly localised in other studies [44]. The lack of any positive T. b. gambiense in the two animal populations sampled correlates with a previous study carried out in the same area [18], indicating that it is unlikely either cattle or pigs are acting as cryptic reservoirs of disease.…”

Analysis of pig trading networks and practices in Uganda

“…The Democratic Republic of Congo's total consumption of pork is expected to increase by 100%, Tanzania by 32%, and Kenya by 25% between 2000 and 2030 (Food and Agriculture Organization 2011). Introduction and expansion of pig production systems in these biodiverse landscapes may create new risks, including pathogen transfer from pigs to humans (Ocaido et al 2013;Wilson 2017;Food and Agriculture Organization (FAO) 2012; Atherstone et al 2015;Hamill et al 2013; Electronic supplementary material The online version of this article (https://doi.org/10.1007/s11250-018-1668-6) contains supplementary material, which is available to authorized users. Agriculture Organization 2017).…”

Trypanosomiaisis in Non Migratory Cattle in Suburban Kaduna

“…African animal trypanosomiasis is also becoming increasingly prevalent beyond its traditionally defined realm with studies showing that Trypanosoma brucei populations in cattle (and other domestic animals) could serve as reservoirs for the human infective subspecies of trypanosomes (Welburn et al, 2001;Njiokou et al, 2010;Karshima et al, 2012;Hamil et al, 2013;Auty et al, 2015). The movement of cattle is also being implicated in the spread and seeding of human disease outbreaks caused by this pathogen.…”