An appraisal on occurrence of anopheline species as a marker of malaria transmission rate in irrigation site in Bunkure, Kano Nigeria
Malaria is an Anopheline mosquito-borne parasitic disease endemic to sub – Saharan Africa, which causes nearly 600,000 deaths every year. The distribution and transmission pattern are known to be affected by the ecological condition of the environment especially water and mesophilic conditions. Accordingly, irrigation-based rice producing system at Bunkure local government area of Kano state, Nigeria was followed up to assess malaria transmission rates. Four hundred and twenty-four (424) adult female Anopheles mosquitoes attracted to man were collected between August, 2010 and January, 2011 in wet and dry seasons in Bunkure Kano State. They were identified with a hand lens and taxonomic keys. The frequency of isolated Anopheline species constitutes 170 (33.2%) Anopheles gambiae and 129 (25.2%) Anopheles funestus for the wet season (August to October) vis-à-vis 72 (32.6%) Anopheles gambiae and 53(23.9%) Anopheles funestus for the dry season (November to January). Anopheline abundance were found in wet season. Mosquitoes that received blood meal were used to determine man biting rate. Blood fed were seen in both mosquitoes’ species in irrigation system with man biting rate (MBR) per day, per month and per year 8.03, 240.6 and 2887.2 respectively. It was concluded that Bunkure LGA irrigation system area has high malaria transmission rate. The main entomological factors influenced malaria transmissions were the vector abundance, human blood index and daily survival rate. These factors were influenced by temperature, humidity, rainfall etc. This study provides information required for formulating vector control programmes to curtail malaria transmission in irrigated areas.
Keywords: Anopheles gambiae, Anopheles funestus, Man biting rate, Irrigation, Sites, Malaria transmission