Parasitological, Serological and Molecular Survey of Camel Trypanosomosis (Surra) in Northern Nigeria

Abstract Surra, a parasitic disease caused by Trypanosoma evansi and transmitted non-cyclically by biting flies significantly affects the health, productivity and market value of camels thereby constituting a major constraint to food safety, security and economy. This is the first study on the prevalence of surra in Northern Nigeria, using a broad variety of diagnostic tests along the parasitological-serological-molecular continuum hence, emphasizing it as a major enzootic risk for camels in Nigeria. In this cross-sectional study, 600 blood samples were collected from camels at major abattoirs in Northwestern Nigeria and evaluated for the prevalence of surra due to T. evansi using parasitological (Giemsa staining), serological (CATT/T.evansi) and molecular (VSG-PCR and sequencing) methods. The overall prevalence of surra recorded in this study was 5.3%, 11.5% and 22.5% using Giemsa stained blood smears, CATT/T.evansi and VSG-PCR respectively. However, higher prevalence of 6.0%, 13.7% and 26.7% by Giemsa stained blood smears, CATT/T. evansi and VSG-PCR was recorded in Katsina state when compared with Kano state. A significantly (p < 0.05) higher prevalence byVSG-PCR was observed when compared with both parasitological and serological methods used. Although age and body condition scores were associated (p < 0.05) with surra prevalence in sampled camels, no seasonal association (p > 0.05) was however recorded. Sequencing of the VSG region of Trypanosoma spp. Further confirmed the presence of T. evansi as the aetiological agent of surra from the sampled camels. Findings from this study call for the implementation of adequate control measures aimed at reducing the impact of T. evansi infections on camel production in Nigeria.