Spiroplasma, Wolbachia, Sodalis and trypanosome associations in Glossina Tachinoides from Yankari game reserve, Nigeria.

BACKGROUND

Tsetse flies are vectors of African trypanosomiasis, a disease that affects both humans and animals. Trypanosomiasis remains a threat to lives and it is an impediment to socio-economic development in sub-Saharan Africa. In spite of decades of chemotherapy and vector control, the disease has not been eradicated. Parasitic drug resistance has been developed to existing drugs, while vector control strategies are expensive and unsustainable. Therefore, there is a need to explore other control approaches, such as the transformation of tsetse fly endosymbionts to render the fly refractory to trypanosome infection. This research focused on investigating the prevalence and triparty association of infection of trypanosomes with some endosymbionts of tsetse flies from Yankari Game Reserve.

METHODS

Tsetse flies were captured using biconical traps, identified morphologically, dissected and their entire guts were isolated and used for DNA extraction. Polymerase Chain Reaction (PCR) was used in confirming the identity of the tsetse flies by amplifying the cytochrome C oxidase-1 gene. PCR was also used to screen for the presence of endosymbionts (Sodalis glossinidius, Wolbachia, and Spiroplasma sp.) and trypanosomes.

RESULTS

Glossina tachinoides was the only vector species identified. Trypanosome infection rate was 10.70% with Trypanosoma grayi being the most prevalent (9.78%) amongst the three trypanosome species detected. The prevalence of Wolbachia and Spiroplasma species were 2.80% and 40.8% respectively in flies. Sodalis glossinidius was not detected. There was an association between the presence of trypanosomes and Wolbachia, while no association was depicted between trypanosomes and Spiroplasma.

CONCLUSION

It has been observed from this study that the presence of Wolbachia seems to favour trypanosome infections. Investigation on the Wolbachia genetic polymorphism in tsetse could help to better understand this association.