Background: To combat malaria, the Kenya Ministry of Health and nongovernmental organizations (NGOs) have distributed insecticide-treated nets (ITNs) for use over beds, with coverage for children under five years of age increasing rapidly. Nevertheless, residents of fishing villages have started to use these bed nets for drying fish and fishing in Lake Victoria. This study investigated the extent of bed net misuse in fishing villages.

Background: The water level of Lake Victoria has fallen more than 1.5 m since 1998, revealing a narrow strip of land along the shore. This study determined whether the recent drop in the water level has created additional breeding grounds for malaria vectors.

Abstract. Polymerase chain reaction (PCR) analysis was performed to determine whether mosquito predators in wetland habitats feed on Anopheles gambiae sensu lato (s.l.) larvae. Aquatic mosquito predators were collected from six wetlands near Lake Victoria in Mbita, Western Kenya. This study revealed that the whole positive rate of An. gambiae s.l. from 330 predators was 54.2%. The order of positive rate was the highest in Odonata (70.2%), followed by Hemiptera (62.8%), Amphibia (41.7%), and Coleoptera (18%). The study demonstrates that the PCR method can determine whether aquatic mosquito predators feed on An. gambiae s.l. larvae if the predators have undigested An. gambiae s.l. in their midgut or stomach.

Polymerase chain reaction analysis was performed to determine whether mosquito predators in wetland habitats feed on Anopheles gambiae sensu lato (s.l.) larvae. Aquatic mosquito predators were collected from six wetlands near Lake Victoria in Mbita, Western Kenya. This study revealed that the whole positive rate of An. gambiae s.l. from 330 predators was 54.2%. The order of positive rate was the highest in Odonata (70.2%), followed by Hemiptera (62.8%), Amphibia (41.7%), and Coleoptera (18%). This study demonstrates that the polymerase chain reaction method can determine whether aquatic mosquito predators feed on An. gambiae s.l. larvae if the predators have undigested An. gambiae s.l. in their midgut or stomach. KeywordsAnura; aquatic insect; Coleoptera; Hemiptera; Odonata Despite a long history of efforts to control malaria, malaria remains a major threat to human health. Because the development of a vaccine for malaria has been slow, and parasite resistance to antimalaria drugs is developing rapidly, vector control is considered the most practical method for reducing malaria transmission in developing countries (Trape et al. 2002, Fillinger et al. 2004. Common measures for malaria vector control include bed nets and indoor residual spray using DDT or pyrethroids (Kouznetsov 1977, Lindblade et al. 2006. However, there is concern about toxicity to nontarget organisms (Henry and Kishimba 2006) and vector resistance to chemical insecticides (Corbel et al. 2003, Etang et al. 2003, Hargreaves et al. 2003, Casimiro et al. 2006. Because chemical insecticides also kill predators of mosquitoes (Service 1977), the reduction of predators may increase vectors; therefore, the use of chemical insecticides requires caution.Among the various natural ecological forces controlling vector populations, predation on immature Anopheles gambiae sensu lato (s.l.) appears to be a major factor controlling population size. Predation on An. gambiae larvae contributes considerably (between 13.4 and 84.5%; Chandler and Highton 1977) to overall larval mortality (between 92.6 and 97.1%; 2 Corresponding author: Center for Ecological Research, Kyoto University, 2-509-3 Hirano, Otsu 520-2113, Japan (oobug@hotmail.com). Service 1971Service , 1973Service , 1977. However, little research has been devoted to the effects of larval predation on mosquito population structure and ecology, possibly because of difficulties in identifying and quantifying the impact of the most common predators in the field. NIH Public AccessUsing the serological method, Service (1973Service ( , 1977 found that predators of An. gambiae s.l. include amphibians as well as the insects from the orders Araneida, Odonata, Hemiptera, Hymenoptera, Diptera, and Coleoptera. Schielke et al. (2007) showed that An. gambiae s.l. DNA can be detected after ingestion by members of the families Lestidae (Odonata), Libellulidae (Odonata), and Notonectidae (Hemiptera). Although the authors fed single laboratory-raised An. gambiae sensu stricto to the predators under laboratory condit...