| Summary: | Background & objectives: Zooprophylaxis is a strategy that can control malaria by attractingmosquitoes to domestic animals that act as dead-end hosts. The objective of this study was toestablish the effects of zooprophylaxis and long-lasting insecticidal nets (LLINs) on malariatransmission in an agro-based ecosystem with seasonal transmission.Methods: The mosquito samples were collected indoors using the space spray catch method beforeand after intervention between October 2005 and March 2006 to determine the mosquito densitiesand the feeding patterns of Anopheles spp in Mwea, Kenya.Results: A total of 4148 mosquito samples were collected, out of which 11 (0.2%) were testedpositive for sporozoites. Ten were Anopheles gambiae species and one was An. funestus species.Results on blood meal ELISA showed that in the household categories that used bednets and keptone cow there was a decrease in relative change ratio (post-/pre-intervention) of 87.5 and 19.6%(p <0.05) in human and cattle blood intake respectively. For households that kept 2–4 cattle andused bednets, there was a decrease in cattle blood index (CBI) by 61.9% and an increase in humanblood index (HBI) by 2%, which was not significant (p >0.05). In households with >4 cattle andbednet, there was significant reduction (p <0.05) in CBI of 37.5% as compared to the reduction of10.3% in HBI. The ratios of man biting rates (MBR) decreased significantly, as you move up fromhouseholds with one cattle with or without LLINs to households with more than four cattle with orwithout LLINs with a regression coefficient of –0.96; SE = 0.834; p = 0.017. Similarly, the HBIdecreased significantly with the regression coefficient of 0.239; SE = 0.039; p = 0.015 (p <0.05)especially in households with >4 cattle.Interpretation & conclusion: This study demonstrated that there were additive effects of zooprophylaxisand LLINs in the control of mosquito density and reduction of human risk to themosquito bites. However, in Integrated Vector Management (IVM), the number of animals perhousehold should not be more than four.
|
|---|
