Trypanosome infections in animals from tsetse infected areas of Cameroon and their sensitivity and resistance molecular profiles for diminazene aceturate and isometamidium chloride.

Monitoring and assessment of control strategies for African trypanosomoses' elimination require not only updating data on trypanosome infections, but also to have an overview on the molecular profiles of trypanocides resistance in different epidemiological settings. This study was designed to determine, in animals from six tsetse-infested areas of Cameroon, the prevalence of trypanosome infections as well as the diminazene aceturate (DA) and isometamidium chloride (ISM) sensitivity/resistance molecular profiles of these trypanosomes. From 2016 to 2019, blood was collected in pigs, dogs, sheep, goats and cattle from six tsetse infested areas of Cameroon. DNA was extracted from blood and trypanosome species were identified by PCR. The sensitivity/resistance molecular profiles of trypanosomes to DA and ISM were investigated using PCR-RFLP. From 1343 blood samples collected, Trypanosoma vivax, Trypanosoma congolense forest and savannah, Trypanosoma theileri and trypanosomes of the sub-genus Trypanozoon were identified. The overall prevalence of trypanosome infections was 18.7%. These prevalence vary between trypanosome species, animal taxa, within and between sampling sites. Trypanosoma theileri was the predominant species with an infection rate of 12.1%. Trypanosomes showing resistant molecular profiles for ISM and DA were identified in animals from Tibati (2.7% for ISM and 65.6% for DA) and Kontcha (0.3% for ISM and 6.2% for DA). No trypanosome carrying resistant molecular profile for any of the two trypanocides was detected in animals from Fontem, Campo, Bipindi and Touboro. Mixed molecular profiles of sensitive/resistant trypanosomes were detected in animals from Tibati and Kontcha. Results of this study highlighted the presence of various trypanosome species as well as parasites carrying sensitive/resistant molecular profiles for DA and ISM in animals of tsetse infested areas of Cameroon. They indicate that the control strategies must be adapted according to epidemiological settings. The diversity of trypanosomes indicates that AAT remains a serious threat for animal breeding and animal health in these tsetse infested areas.