Aim: The effect of Host blood on the fecundity of female Anopheles gambiae sensu lato mosquitoes was studied under normal conditions of 64±2% Relative Humidity and 27±2ºC Temperature. Methods: Three-five day old (F1) female Anopheles mosquitoes were transferred into wooden cages (40x40x40 cm) and fed blood from the following sources: man, cattle, chicken, goat, pig and sheep through an artificial feeding membrane. Engorged females were observed and fecundity recorded. The entire experiment was replicated five (5) times. Results: From the 1st to 4th gonotropic cycle, mosquitoes fed human blood produced significantly greater (p<0.05) number of eggs (Mean=121.90±1.18, 101.36±1.56, 64.12±1.54 and 29.66±1.69 respectively) than mosquitoes fed other blood meal sources. Across the six (6) blood meal trials (excluding that of sheep), there was a significant reduction (p<0.05) in fecundity from the 1st to 4th gonotropic cycles (1st>2nd>3rd>4th). There was no significant difference (p>0.05) in fecundity between pigs, chicken and sheep. Total mean longevity and total mean fecundity was significantly greater (p<0.05) in mosquitoes fed human and cattle blood than in mosquitoes fed the other blood sources. Conclusion: The results showed that blood meal source affects fecundity and longevity of female Anopheles gambiae s. l mosquitoes reared under laboratory conditions and that blood from humans as well as from other domestic animals is suitable for sustaining vectorial capacity in Anopheles gambiae s. l mosquitoes.

A survey was carried out in Vandeikya Local Government Area of Benue State, Nigeria from April-July 2017 to determine availability of freshwater snails of and their preferred habitats. A total of 289 fresh water snails of four different genera were collected across 27 streams in the 7 districts in Vandeikya LGA. Water pH, water temperature and water velocity were also measured. Lenistislibycuswas found to be the most abundant freshwater snail species accounting for 40.83% of the total freshwater snails. Melanoidestuberculata was the second most abundant accounting for 29.411% of the total snails population sampled, Biomphalaria pfeifferi accounted for 17.99% while Bulinus globosus was significantly lower in abundance than the other snails, accounting for only 11.77%. By location, Mbaduku district had highest abundance of snails 84 (29.1%). The effect of the nature of the substratum on the availability of freshwater snails revealed that habitats with rocky substratum favoured the presence of snails accounting for 181(62.7%) freshwater snail collected.Our understanding of factors affecting the availability and abundance of freshwater snails in nature can prove useful in snail control which is integral for the control of the diseases for which they serve as intermediate host.

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Schistosomiasis is a neglected tropical disease of medical importance. Intestinal schistosomiasis caused by Schistosoma mansoni is less wide spread than urinary schistosomiasis in Nigeria. A study was carried out in Akwanga, Nasarawa State to determine the association between S. mansoni infection rates (prevalence) in humans and infection rates in Biomphalaria pfeifferi snails in Akwanga, Nasarawa State, Nigeria. The study was carried out in two communities: Gwanje community and MadaHills community in Akwanga. For infection rates in humans, four hundred (400) urine samples were tested for S. mansoni antigen using point of care circulating cathode antigen (POC-CCA) test kit. Infection rates in snails were determined by S. mansoni cercarial shedding by snails. Biomphalaria pfeifferi snails were more abundant and had significantly higher (p<0.05) infection rates in dry season than rainy season in both Gwanje and MadaHills. There was a positive correlation between infection rates in humans in Gwanje and MadaHills (21.5%) and (14%) and infection rates in snails in Gwanje and MadaHills (13.9%) and (9.6%) respectively. Snails collected close to portions of the river that community residents earmarked for open defecation within freshwater bodies had significantly higher (p<0.05) infection rates (15.8%) than snails collected from across river banks, (7.1%) and snail infection rates in areas designated for fetching water for drinking and domestic use was (12.7%) . Health education, improved sanitation practices and annual chemotherapy with praziquantel could help interrupt disease transmission and bring about schistosomiasis control in both Gwanje and MadaHills communities.