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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.

To date, camels still remain an important work animal as well as source of protein to humans in the Sudan and Sahel regions of Nigeria. Therefore, a cross-sectional study was conducted on 150 camels slaughtered in Maiduguri central abattoir to determine the prevalence of Trypanosoma evansi using Card Agglutination Test (CATT) and Polymerase Chain Reaction (PCR) techniques. Overall, 30 (20%) of the camels tested were seropositive while PCR targeting the 227 base pair of the Variable Surface Glycoprotein (VSG) gene of T. evansi detected the DNA of the parasite in 9 out of the 30seropositive camels. Higher infection was found among adult compared to the young camels using the two diagnostic techniques; 24.1% vs 19.0% and 10.3% vs 4.6%, for CATT and PCR techniques, respectively. However, the differences being not statistically significant (P > 0.05) for the two methods of diagnosis. Furthermore, significantly (P < 0.05)higher prevalence of infection was recorded among male compared to female camels using the serological method of diagnosis, while (P > 0.05) using the molecular method; 27.5% vs 13.6% for CATT and 10.1% vs 2.5% for PCR. Camels with PCV =24 %( mean: 19.8923 ± 4.0931) recorded significantly (P < 0.05) higher prevalence of 23.1% than those with PCV = 25% (mean 31.7294 ± 5.50584), where the prevalence was 17.6%.The results of this study showed that camel trypanosomosis is endemic in the study area.  Furtherstudiesto elucidate the epidemiology and socioeconomic impact of this disease in the northeast region of Nigeria are desirable. Keywords:Serology, PCR, Dromedary camel, T.evansi, Maiduguri