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.

Black flies, vectors of Onchocerca volvulus, are known to colonize fast flowing sections of rivers. A study on aspects of ecology of immature forms of black flies was conducted at River Mada. Larvae and Pupae of the Genus: Simulium were prospected on natural substrates found at various water currents along the course of the river over a 12-month period. Larvae of six species and pupae of three species were identified colonizing different substrates in the river. A total of 443 larvae and 142 pupae were collected, and the peak month of collection was April. 405 (91.4%) larvae were identified as S. damnosum sl while 38 (8.6%) comprised S. adersi, S. hargreavesi, S. cervicornotum, S. bovis and S. vorax. 110 (77.5%) of the pupae collected were S. damnosum sl while 32 (22.5%) were S. adersi, and S. hargreavesi. The larvae unlike pupae appeared to be non discriminatory in substrate colonization and current preference. Paucity of the population of immature forms is observed and attributed primarily to scarcity of suitable substrates and other factors also discussed herein.