The origins of the trypanosome genome strains Trypanosoma brucei brucei TREU 927, T. b. gambiense DAL 972, T. vivax Y486 and T. congolense IL3000

The genomes of several tsetse-transmitted African trypanosomes (Trypanosoma brucei brucei, T. b. gambiense, T. vivax, T. congolense) have been sequenced and are available to search online. The trypanosome strains chosen for the genome sequencing projects were selected because they had been well characterised in the laboratory, but all were isolated several decades ago. The purpose of this short review is to provide some background information on the origins and biological characterisation of these strains as a source of reference for future users of the genome data. With high throughput sequencing of many more trypanosome genomes in prospect, it is important to understand the phylogenetic relationships of the genome strains

Managing Tsetse Transmitted Trypanosomosis by Insecticide Treated Nets - an Affordable and Sustainable Method for Resource Poor Pig Farmers in Ghana

An outbreak of tsetse-transmitted trypanosomiasis resulted in more than 50% losses of domestic pigs in the Eastern Region of Ghana (source: Veterinary Services, Accra; April 2007). In a control trial from May 4th–October 10th 2007, the efficacy of insecticide-treated mosquito fences to control tsetse was assessed. Two villages were selected – one serving as control with 14 pigsties and one experimental village where 24 pigsties were protected with insecticide treated mosquito fences. The 100 cm high, 150denier polyester fences with 100 mg/m2 deltamethrin and a UV protector were attached to surrounding timber poles and planks. Bi-monthly monitoring of tsetse densities with 10 geo-referenced bi-conical traps per village showed a reduction of more than 90% in the protected village within two months. Further reductions exceeding 95% were recorded during subsequent months. The tsetse population in the control village was not affected, only displaying seasonal variations. Fifty pigs from each village were ear-tagged and given a single curative treatment with diminazene aceturate (3.5 mg/kg bw) after their blood samples had been taken. The initial trypanosome prevalence amounted to 76% and 72% of protected and control animals, respectively, and decreased to 16% in protected as opposed to 84% in control pigs three months after intervention. After six months 8% of the protected pigs were infected contrasting with 60% in the control group

RAPD analysis of genotypic groups of Trypanosoma congolense and other African trypanosome species

Oligonucleotide primers of arbitrary nucleotide sequences were used in PCR reaction to amplify genomic DNA from the four types of T. congolense: Tsavo-type, Savannah-type, Kilifi-type and West African riverine/ forest-type. Several primers produced significantly different RAPD patterns for the four types of T. congolense. Similarity indices imply that the Kilifi-type and Savannahtype T. congolense (SI; 0.453) are the most closely related evolutionarily among T. congolense whereas the West African riverine/forest-type and Savannah type T. congolense (SI; 0.405) are the most distantly related. RAPD patterns of the four types of T. congolense were also compared with those of other trypanosome species. Similarity indices of this comparison implies that T. evansi and T.b. gambiense (SI; 0.667) are the most closely related whereas Kilifi-type T. congolense and T. b. brucei (SI; 0.315) are the most distantly related. The results further indicate that the T. congolense genotypic groups may be as different as they are from any other trypanosome species studied in this work. Bulletin of Animal Health and Production in Africa Vol. 54(1) 2006: 7-1

Identification of different trypanosome species in the mid-guts of tsetse flies of the Malanga (Kimpese) sleeping sickness focus of the Democratic Republic of Congo

<p>Abstract</p> <p>Background</p> <p>The Malanga sleeping sickness focus of the Democratic Republic of Congo has shown an epidemic evolution of disease during the last century. However, following case detection and treatment, the prevalence of the disease decreased considerably. No active survey has been undertaken in this focus for a couple of years. To understand the current epidemiological status of sleeping sickness as well as the animal African trypanosomiasis in the Malanga focus, we undertook the identification of tsetse blood meals as well as different trypanosome species in flies trapped in this focus.</p> <p>Methods</p> <p>Pyramidal traps were use to trap tsetse flies. All flies caught were identified and live flies were dissected and their mid-guts collected. Fly mid-gut was used for the molecular identification of the blood meal source, as well as for the presence of different trypanosome species.</p> <p>Results</p> <p>About 949 <it>Glossina palpalis palpalis</it> were trapped; 296 (31.2%) of which were dissected, 60 (20.3%) blood meals collected and 57 (19.3%) trypanosome infections identified. The infection rates were 13.4%, 5.1%, 3.5% and 0.4% for <it>Trypanosoma congolense</it> savannah type, <it>Trypanosoma brucei</it> s.l., <it>Trypanosoma congolense</it> forest type and <it>Trypanosoma vivax</it>, respectively. Three mixed infections including <it>Trypanosoma brucei</it> s.l. and <it>Trypanosoma congolense</it> savannah type, and one mixed infection of <it>Trypanosoma vivax</it> and <it>Trypanosoma congolense</it> savannah type were identified<it>.</it> Eleven <it>Trypanosoma brucei gambiense</it> infections were identified; indicating an active circulation of this trypanosome subspecies. Of all the identified blood meals, about 58.3% were identified as being taken on pigs, while 33.3% and 8.3% were from man and other mammals, respectively.</p> <p>Conclusion</p> <p>The presence of <it>Trypanosoma brucei</it> in tsetse mid-guts associated with human blood meals is indicative of an active transmission of this parasite between tsetse and man. The considerable number of pig blood meals combined with the circulation of <it>Trypanosoma brucei gambiense</it> in this focus suggests a transmission cycle involving humans and domestic animals and could hamper eradication strategies. The various species of trypanosomes identified in the Malanga sleeping sickness focus indicates the coexistence of animal and human African Trypanosomiasis. The development of new strategies integrating control measures for human and animal trypanosomiasis may enable the reduction of the control costs in this locality.</p