Discussion
malaria, infection, Ebola virus disease
MALARIA, INFECTION, EBOLA VIRUS DISEASE
Despite decades of mosquito control in Liberia using LLINs and IRS, malaria prevalence remains high. The current study demonstrates partial efficacy of DWL, an approach to mosquito control that is tailored to a typical Liberian house design and is a hybrid of LLINs and IRS. By covering ceilings and windows, the insecticidal material reduced mosquito access to indoor sleeping areas. Installing DWL as a whole house improvement is a promising approach that may provide an effective and appropriate mosquito control measure where LLIN usage is low. Measuring the effect of vector control interventions against malaria is challenging, due to the complexity of the movement of vectors and humans. Modification of housing is especially challenging as uptake is incomplete, and insecticidal materials can be repurposed or modified in unexpected ways. In the current study, an outbreak of Ebola virus disease occurred, which further complicated the installation of DWL and the measurement of its effect.Mosquito control interventions that improve the whole house have been studied in a variety of contexts, but inconsistencies in experimental design and materials make it challenging to define a best practice for deployment of whole-house insecticidal materials. One theme that does emerge from the limited available literature is that covering eaves and other entry points is an important consideration. Disaster relief agencies have tested ITPS in Sierra Leone [Feasibility of DWL as an intervention has been analysed, with various approaches aimed at reducing cost and maximizing acceptability. Recent research into the utility of eave tubes is very encouraging [Study findings indicate a significant effect on malaria prevalence at 12 months post baseline, which was not observed in trials of the most comparable DWL prototypes. DWL was observed to be an effective malaria control product in the Upland (inland) region of Bomi County, but less so in the Coastal region. Differences in effect may be due to more stable malaria transmission characteristics inland, compared to the coastal region. Human behaviour characteristics may also have played a role in reducing malaria control effect in the Coastal region, where families may be engaged in outdoor activities as night, related to fishing. This requires further investigation.Similar prototypes made by the same supplier have been tested in other trials [Mosquito genotyping revealed pyrethroid resistance at similar levels to that reported in 2012 [Coastal villages compared to Upland (inland) villages showed a dramatic drop in overall malaria prevalence (Table Studies in Mozambique with comparable whole house coverage showed marked decrease in indoor biting [Combining insecticide classes by layering a non-pyrethroid wall liner on top of existing LLINs has been studied previously [It is important to highlight that all children that were followed up had been previously cleared of infection by ASAQ treatment [As a hybrid approach that benefits from aspects of successful use of LLINs and IRS, whole-house deployment of DWL is shown here to be partially effective at decreasing malaria in Liberia, despite an unexpected decline in bioefficacy. The decision to cover gables and eaves resulted from community input, an essential component when developing vector control tools [