Improvements in genetic and genomic technology have enabled field-deployable molecular laboratories and these have been deployed in a variety of epidemics that capture headlines. In this editorial, we highlight the importance of building physical and personnel capacity in low and middle income countries to deploy these technologies to improve diagnostics, understand transmission dynamics and provide feedback to endemic communities on actionable timelines. We describe our experiences with molecular field research on schistosomiasis, trypanosomiasis and rabies and urge the wider tropical medicine community to embrace these methods and help build capacity to benefit communities affected by endemic infectious diseases.
African animal trypanosomiasis (AAT), a disease complex caused by tsetse fly–transmitted Trypanosoma brucei brucei, T. congolense savannah ITS, and T. vivax, continues to inflict heavy losses to the animal industry in terms of decreased livestock production and productivity. Live bait technology and chemotherapy have been used as a control strategy in northern Uganda since 2006 with minimal success. Here, we report the results of a cross-sectional study carried out in Lango subregion, Uganda, to assess the species prevalence of bovine trypanosome in cattle using the internal transcribed spacer (ITS) of trypanosome ribosomal DNA (rDNA). Blood samples were collected from 1090 cattle by ear vein puncture and screened using a single pair of primers designed to amplify ITS ribosomal DNA (rDNA). Our results indicate an overall prevalence of 40.18% (438/1090, 95% CI 30.82–54.51). T. vivax constituted 32.66% (356/1090), T. congolense 2.39% (26/1090), T. brucei 1.28% (14/1090), T. godfreyi 0.09%(1/1090), T. brucei and T. congolense 0.36% (4/1090), T. brucei and T. vivax 1.47% (16/1090), T. vivax and T. congolense 1.65% (18/1090), T. vivax and T. simiae 0.18% (2/1090), and T. vivax and T. godfreyi 0.09% (1/1090) of infections. Over 91.7% of infections involved single species, while 9.5% were mixed infections. Over 90.2% (37/41) of the mixed infections involved T. vivax as one of the species, while 53.7% (22/41) involved T. congolense. The high prevalence of AAT and the continued presence of T. brucei raise public health concerns because of the zoonotic implications. An integrated approach that involves mass treatment of cattle, vector, and animal movement control should be adopted to reduce the risk of both AAT and HAT.
African animal trypanosomiasis (AAT) continues to inflict heavy losses on livestock production especially cattle in terms of decreased production and productivity in Uganda. AAT is a disease complex caused by tsetse fly-transmitted Trypanosoma brucei brucei, Trypanosoma brucei rhodesiense, Trypanosoma congolense, and Trypanosoma vivax. The disease is most important in cattle but also known to cause serious losses in pigs, camels, goats, and sheep. Several control measures including live bait technology, mass treatment of cattle with trypanocidal drugs, and deployment of tsetse traps have been used in the past 10 years, but the problem still persists in some areas. This necessitated an exploration of the factors associated with continued trypanosome infections in cattle, which are also known reservoirs for the zoonotic trypanosomiasis. A structured questionnaire was administered to 286 animal owners from 20 villages purposively selected from Lira, Kole, and Alebtong districts of Lango subregion to obtain information on the factors associated with persistence of infection. Over 50% of the respondents reported trypanosomiasis as a major challenge to their livestock. Land ownership (P = 0.029), type of livestock kept (P = 0.000), disease control strategy employed (P = 0.000), source of drugs (P = 0.046), and drug preparation (P = 0.017) were associated with persistent AAT infection. We recommend continued farmer sensitization on the threat of AAT and the available prevention and control options. The use of isometamidium chloride for prophylaxis against trypanosomiasis is highly recommended. There is also a need to foster qualified private veterinary drug supply in the region.
In 2005, the zoonotic acute sleeping sickness was spreading rapidly from the endemic areas of southeastern Uganda with potential for merger into areas affected by the chronic form of the disease in northwest Uganda. Movement of cattle reservoirs due to restocking was blamed for the rapid spread. To stop the spread of the zoonotic sleeping sickness, cattle in the disease endemic areas had to be treated with trypanocidal drugs and sprayed with deltamethrin to promote the live bait technology that helps suppress the tsetse vector. The initiative that started in five high-risk districts in 2006 with a mix of using several undergraduate veterinary students has now been integrated in the local government veterinary service delivery in 23 high-risk districts. By 2016, the annual spray of cattle with deltamethrin and treatment with diminazene aceturate had reached one million with 1,065,444 cattle sprayed in the reporting year July 1, 2016 to June 30, 2017. This is believed to have contributed significantly to the reduction in the number of Trypanosoma brucei rhodesiense sleeping sickness cases (from 473 recorded in 2005 to 14 in 2016, and only about 10 reported to the Coordinating Office for Control of Trypanosomiasis in Uganda [COCTU] in 2017). The initiative that started as the Stamp Out Sleeping Sickness Consortium with a public good approach, implemented in a public-private partnership with the faculty of Veterinary Medicine, Makerere University, has today been integrated in both private and public sectors to fast-track the elimination of T. b. rhodesiense sleeping sickness with active financial contribution from the affected communities in sustaining the delivery of live bait technology.