Effect of Metofluthrin-Impregnated Spatial Repellent Devices Combined with New Long-Lasting Insecticidal Nets (Olyset® Plus) on Pyrethroid-Resistant Malaria Vectors and Malaria Prevalence: Field Trial in South-Eastern Malawi.

Long-lasting insecticidal nets (LLINs) experience some operational problems that reduce their effectiveness, such as limited spaces for hanging, biting of mosquitoes outdoors, a shift of key biting time from midnight to dawn or dusk, and development of pyrethroid resistance in mosquitoes. The concept of spatial repellency may be a countermeasure to overcome the above issues. The effect of the combined use of metofluthrin-impregnated spatial repellent devices (MSRDs) and LLINs (Olyset® Plus) on malaria prevalence and vector mosquitoes were examined in malaria endemic villages in south-eastern Malawi. The intervention reduced the infection rate in children as well as the number of pyrethroid-resistant vector mosquitoes. To achieve effective malaria control, continued intervention using MSRDs with 2 strips per 10 m2 at 3-month intervals to reduce the density of malaria mosquitoes is recommended.

Beyond buzzing: mosquito watching stimulates malaria bednet use-a household-based cluster-randomized controlled assessor blind educational trial.

Malaria remains a severe health problem in Sub-Saharan Africa, with approximately one million deaths and 365 million cases each year. In terms of malaria control, insecticide-treated bednets are an effective tool, and many organizations have distributed free or highly subsidized bednets in malaria endemic areas. Nevertheless, some recipients do not use bednets because of social, environmental or cultural factors. Making vulnerable populations aware of the presence of mosquitoes may improve bednet use among people owning but not using a bednet. We hypothesized that showing freshly collected mosquitoes from the vicinity could improve bednet use in households owning but not using bednets. To test this hypothesis, we applied a household-based cluster-randomized controlled assessor blind educational trial. Indirect observation of mosquitoes, via educational leaflets, produced no change in bednet use, while showing freshly captured mosquitoes led to a 13-fold increase in bednet use. Our results suggest that direct observation of freshly captured mosquitoes can encourage bednet use and may potentially improve effective bednet coverage for malaria control and elimination.