Scaling up of insecticide treated nets has contributed to a substantial malaria decline. However, some malaria vectors, and most arbovirus vectors, bite outdoors and in the early evening. Therefore, topically applied insect repellents may provide crucial additional protection against mosquito-borne pathogens. Among topical repellents, DEET is the most commonly used, followed by others such as picaridin. The protective efficacy of two formulated picaridin repellents against mosquito bites, including arbovirus and malaria vectors, was evaluated in a field study in Cambodia. Over a period of two years, human landing collections were performed on repellent treated persons, with rotation to account for the effect of collection place, time and individual collector. Based on a total of 4996 mosquitoes collected on negative control persons, the overall five hour protection rate was 97.4% [95%CI: 97.1–97.8%], not decreasing over time. Picaridin 20% performed equally well as DEET 20% and better than picaridin 10%. Repellents performed better against Mansonia and Culex spp. as compared to aedines and anophelines. A lower performance was observed against Aedes albopictus as compared to Aedes aegypti, and against Anopheles barbirostris as compared to several vector species. Parity rates were higher in vectors collected on repellent treated person as compared to control persons. As such, field evaluation shows that repellents can provide additional personal protection against early and outdoor biting malaria and arbovirus vectors, with excellent protection up to five hours after application. The heterogeneity in repellent sensitivity between mosquito genera and vector species could however impact the efficacy of repellents in public health programs. Considering its excellent performance and potential to protect against early and outdoor biting vectors, as well as its higher acceptability as compared to DEET, picaridin is an appropriate product to evaluate the epidemiological impact of large scale use of topical repellents on arthropod borne diseases.

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The dTph1 transposable element family of Petunia hybrida line W138 consists of between 100 and 200 members. A strategy that allows simultaneous detection of individual elements is described. Sequences flanking dTph1 elements are amplified by means of a ligation-mediated PCR. The resulting fragments are locus-specific and can be analysed by polyacrylamide gel electrophoresis. One of the applications of Transposon Display is the isolation of dTph1-tagged genes. Fragments that co-segregate with a mutant phenotype can be extracted from the gel and reamplified, providing access to tagged genes, as demonstrated in a reconstruction experiment. Data on the molecular identification of a phenotypic mutant, isolated in a random tagging experiment is also presented. Upon sequencing, the obtained candidate fragment was found to be identical to part of the previously identified Fbp1 gene.

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This study uses data on income and distribution of relief payments from local poor relief tables for 512 rural parishes in Flanders (present-day Belgium) in 1807 to examine spatial variation in poor relief practices in a region characterised by well-established local poor relief institutions and marked socio-economic differences. By combining data on poor relief with local data on population, landholding and occupational structure, we map out the relative importance of regional economies and local variation in producing distinct poor relief regimes. The results show that although local variation was considerable, the nature and extent of this variation interacted with structural socio-economic characteristics to produce regional patterns, signalling that local variation did not so much contradict as constitute regional patterns in poor relief regimes. The importance of socio-economic characteristics in determining both regional patterns and local variation supports our more general contention that local and regional levels of analysis represent a more fruitful avenue for understanding variations in poor relief practices than national differences in legislation, and therefore has implications for the comparative study of poor relief practices in a wider international context.