The primary outcome measure is parasite prevalence in the evaluation zone. of the intervention will be determined inside and up to 500 m outside the targeted hotspots by PCR-based parasite prevalence in cross-sectional surveys, malaria morbidity by passive case detection in selected facilities and entomological monitoring of larval and adult populations. Discussion This study aims to provide direct evidence for a community effect of hotspot-targeted interventions. The trial is powered to detect large effects on malaria transmission in the context of ongoing malaria interventions. Follow-up studies will be needed to determine the effect of individual components of the interventions and the cost-effectiveness of a hotspot-targeted approach, where savings made by reducing the number of compounds that need to receive interventions ABT-639 hydrochloride should outweigh the costs of hotspot-detection. Trial registration “type”:”clinical-trial”,”attrs”:”text”:”NCT01575613″,”term_id”:”NCT01575613″NCT01575613. The protocol was registered online on 20 March 2012; the first community was randomized on 26 March 2012. apical membrane antigen (AMA-1) and merozoite surface protein 1 (MSP-119) will be detected by ELISA using standard methodology [27,28]. Three serological outcome measures will be used to determine spatial patterns in malaria exposure: (i) the combined antibody prevalence, that is, seropositivity for AMA-1 and MSP-119 or for either of the antigens alone; (ii) the age-adjusted log10-transformed optical density (OD) [21,29]; (iii) the age-dependent sero-conversion rate (SCR) for combined AMA-1, MSP-119 antibody prevalence [21,27]. Definition of hotspotsSaTScan software [30] will be used for the detection of spatial clustering in antibody prevalence (Bernouilli model) and log10-transformed age-adjusted OD values (normal probability model). Circular and elliptic windows [30,31] will be used to systematically scan the study area as a whole and segments of the study area using a 2 4 km rolling window. Hotspots will be allowed to be 1 km in radius and include 25% of the population of each window scanned. Segments of the study area will be scanned to improve the sensitivity of the scan to detect local hotspots. Local hotspots may not be detected when scanning the area as a whole, since altitude differences in the study area result in variations in average levels of transmission intensity. A hotspot will be defined as an area for which there is strong evidence ( 0.05) that the observed prevalence or density of combined AMA-1 and MSP-119 antimalarial antibodies is higher than expected values. Expected values are based on average values for the area as a whole and for the 2 2 4 km rolling window. Since malaria antibodies are relatively long-lived and may indicate current as well as past malaria exposure, parasite prevalence inside and outside hotspots of malaria exposure will be determined by PCR to confirm ongoing transmission in serologically defined hotspots. Selection of hotspots and evaluation areasSince habitation in the study area is fairly evenly distributed, with every 500 500 m cell having six or more residential structures, clusters are unlikely to be isolated geographically. To minimize the influence of neighbouring hotspots on malaria transmission in selected intervention or ABT-639 hydrochloride control hotspots, we will select hotspots for which there are no other hotspots detected within 1 km in any direction from the hotspot boundary. The hotspot-targeted intervention will be evaluated in the area surrounding the hotspot (evaluation zones). The evaluation zone will comprise the area surrounding the hotspot up to 500 m from the hotspot boundary in each direction. Design of the intervention Intervention clustersFour interventions will be rolled out in the period preceding the long rainy season: larviciding, focal screening and treatment (FSAT), long-lasting insecticide-treated nets (LLIN) distribution and IRS. The details of interventions, and their timing, have been agreed upon in collaboration with the DOMC of the Kenyan Ministry of Public Health and Sanitation (MOPHS). Ten per cent of households will be visited 1 to 2 2 weeks after the intervention to assess any short-term side effects of the FSAT, LLINs and IRS. This sampling strategy was not based on sample size calculations but on logistical feasibility; few side E1AF effects were expected. LarvicidingAll permanent aquatic mosquito habitats in intervention hotspots will be mapped using handheld GPS receivers during the dry season. In the period preceding the long rainy season (April), and throughout the long rainy season (until September) all stagnant water bodies (permanent and temporary) inside these hotspots will ABT-639 hydrochloride be treated on a weekly basis with water-dispersible granule formulations of the commercial strains of (Bti), VectoBac?, which will be provided by Valent BioSciences Corp.,.
