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Background: Exposure to radiofrequency electromagnetic fields (RF-EMF) is often measured with personal exposimeters, but the accuracy of measurements can be hampered as carrying the devices on-body may result in body shielding. Further, the compact design may compromise the frequency selectivity of the sensor. The aim of this study was to compare measurements obtained using a multi-band body-worn distributed-exposimeter (BWDM) with two commercially available personal exposimeters (ExpoM-RF and EmeSpy 200) under real-life conditions. Methods: The BWDM measured power density in 10 frequency bands (800, 900, 1800, 2100, 2600 MHz, DECT 1900 MHz, WiFi 2.4 GHz; with separate uplink/downlink bands for 900, 1800 and 2100 MHz); using 20 separate antennas integrated in a vest and placed on diametrically opposite locations on the body, to minimize body-shielding. RF-EMF exposure data were collected from several microenvironments (e.g. shopping areas, train stations, outdoor rural/ urban residential environments, etc.) by walking around pre-defined areas/routes in Belgium, Spain, France, the Netherlands and Switzerland. Measurements were taken every 1-4 s with the BWDM in parallel with an ExpoM-RF and an EmeSpy 200 exposimeter. We calculated medians and interquartile ranges (IQRs) and compared difference, ratios and correlations of geometric mean RF-EMF exposure levels per microenvironment as measured with the exposimeters and the BWDM. Results: Across 267 microenvironments, medians and IQR of total BWDM measured RF-EMF exposure was 0.13 (0.05-0.33) mW/m2. Difference: IQR of exposimeters minus BWDM exposure levels was -0.011 (-0.049 to 0.0095) mW/m2 for the ExpoM-RF and -0.056 (-0.14 to -0.017) for the EmeSpy 200; ratios (exposimeter/BWDM) of total exposure had an IQR of 0.79 (0.55-1.1) for the ExpoM-RF and 0.29 (0.22-0.38) for the EmeSpy 200. Spearman correlations were 0.93 for the ExpoM-RF vs the BWDM and 0.96 for the EmeSpy 200 vs the BWDM. Discussion and conclusions: Results indicate that exposimeters worn on-body provide somewhat lower total RF-EMF exposure as compared to measurements conducted with the BWDM, in line with effects from body shielding. Ranking of exposure levels of microenvironments showed high correspondence between the different device types. Our results are informative for the interpretation of existing epidemiological research results. Grant Sponsors: This research was funded by the National Research Program of the French Agency for Food, Environmental and Occupational Health and Safety (ANSES), grant No 2015-2-RF-07, and the equipment was supported by funding from the European Commission Seventh Framework Programme under grant agreement number FP7 603794 (GERoNiMO). Our funders had no involvement in the study design; data collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the article for publication.

We characterized exposure to RF-EMF in 357 different unique microenvironments in five European countries, using two personal exposimeters, as well as a vest with integrated sensors. We found substantial exposure differences between large cities, medium-sized townsand small villages, and found consistently higher total exposures in central, busy places with many people (business, shopping districts) than in quieter, residential areas.

We developed a new RF-EMF meter with sensors distributed over the front and back side of a vest, performed measurements in different microenvironments in five countries and compared results with commercially available exposimeters that are frequently used in epidemiological studies.

International audience; The aim of this study is to compare measurement results of a newly developed prototype of a multiband body-worn distributed-exposimeter (BWDM) with two commercially available personal exposimeters (EXPOM and EME SPY 200).We are currently conducting field measurements in various indoor and outdoor microenvironments in Belgium, Spain, France, Netherlands and Switzerland.Our data will allow the comparison of the measurements of the three different exposimeters and will be informativebetter understanding and interpretation of existing epidemiological research results.

International audience; Human exposure to radiofrequency electromagnetic fields (RF-EMF) is often measured by personal exposimeters. However, available portable devices are compromised by the presence of the human body and have large measurement uncertainties. The aim of this study was to compare measurement results of a newly developed prototype of a multi-band body-worn distributed-exposimeter (BWDM) with two commercially available personal exposimeters (EXPOM and EME SPY 200). The BWDM prototype has been developed for simultaneous measurement of the incident power density in 11 frequency bands (LTE 800 and 2600 MHz, 900 MHz, 1800 MHz, 2100 MHz, DECT, Wi-Fi 2 GHz and 5 GHz, including uplink and downlink bands). The BWDM consists of 22 textile antennas integrated in a garment, distributed in an optimal way on the front and back of the human torso as well as right and left hips. For all frequency bands, antenna pairs are placed on diametrically opposite locations on body, for minimizing body-shielding. Since 2016, field measurements are being conducted in various indoor and outdoor microenvironments in Belgium, Spain, France, Netherlands and Switzerland. In each country, a trained research assistant is using the BWDM in parallel with EXPOM and EME SPY 200 exposimeters by walking along pre-defined measurement routes, comparing different characteristic microenvironments such as urban, suburban and rural areas, public transport infrastructure, and public areas such as universities, parks and shopping centres. In a first step of data analysis, the results of the measurement in Switzerland from November and December 2016 will be used to compare the measurements of the three different exposimeters. The results of the device comparisons will enable a better understanding and interpretation of existing epidemiological research results, as well as improved risk assessment and communication strategies.

International audience; Human exposure to radio frequency (RF) radiation is usu-ally measured by personal exposimeters (PEMs). The main issue of PEMs is that the presence of the human body results in large uncertainties up to 35 dB. For the first time, a multi-band multi-node wearable dis-tributed RF exposure meter (MBWE) is designed and cali-brated on body. The goal is to reduce the influence of human body on measurements of the MBWE. This is achieved in terms of on-body calibrations. Moreover, the MBWE is cali-brated on five human subjects to assess the influence of hu-man body on its measurement uncertainty.

International audience; In the ongoing task of the World Health Organization (WHO) to develop Environment Health Criteria (EHC) for radio frequency (RF) electromagnetic fields (EMF), literature published after 1991 will be included. This presentation focus on studies that have been published in the period 2011-2015. Studies that complied with the predefined inclusion criteria include outcomes related to cognitive performance, brain electrical activity, brain metabolism and blood flow, symptoms, well-being and exposure detection, cardiovascular and autonomic nervous systems and temperature. For most endpoints only a few studies suggested a possible effect of exposure, while for electrical brain activity, effects were suggested in most studies.

This study investigated whether passively collected routine health facility data can be used for mapping spatial heterogeneities in malaria transmission at the level of local government housing cluster administrative units in Dar es Salaam, Tanzania. From June 2012 to Jan 2013, residential locations of patients tested for malaria at a public health facility were traced based on their local leaders’ names and geo-referencing the point locations of these leaders’ houses. Geographic information systems (GIS) were used to visualise the spatial distribution of malaria infection rates. Spatial scan statistics were deployed to detect spatial clustering of high infection rates. Among 2,407 patients tested for malaria, 46.6% (1,121) could be traced to their 411 different residential housing clusters. One small spatially aggregated cluster of neighbourhoods with high prevalence was identified. While the home residence housing cluster leader was unambiguously identified for 73.8% (240/325) of malaria-positive patients, only 42.3% (881/2,082) of those with negative test results were successfully traced. It was concluded that recording simple points of reference during routine health facility visits can be used for mapping malaria infection burden on very fine geographic scales, potentially offering a feasible approach to rational geographic targeting of malaria control interventions. However, in order to tap the full potential of this approach, it would be necessary to optimise patient tracing success and eliminate biases by blinding personnel to test results.

One of the main challenges to malaria elimination is the resilience of vectors, such as Anopheles arabiensis, that evade lethal exposure to insecticidal control measures or express resistance to their active ingredients. This study investigated a novel technology for population control that sterilizes mosquitoes using pyriproxyfen, a juvenile hormone analogue. Females of An. arabiensis were released in a semifield system divided into four equal sections, and each section had a mud hut sheltering a tethered cow providing a blood source for mosquitoes. In all sections, the inner mud hut walls and roofs were lined with black cotton cloth. In one-half of the sections, the cloth was dusted with pyriproxyfen. An overwhelming 96% reduction in adult production was achieved in pyriproxyfen-treated sections compared with control sections. This unprecedented level of control can be exploited to design new vector control strategies that particularly target existing behaviorally resilient and insecticide-resistant populations.

BACKGROUND\ud \ud Insecticide resistance poses a major threat to current vector control campaigns. Insecticides with novel modes of action are therefore in high demand. Pyriproxyfen (PPF), a conventional mosquito pupacide, has a unique mode of action that also sterilises adult mosquitoes (unable to produce viable offspring) upon direct contact. However, the timing of PPF exposure in relation to when mosquitoes take a blood meal has an important impact on that sterilisation. This study investigated the relationship between different blood feeding and PPF exposure timings to determine the potential of PPF sterilisation in controlling Anopheles arabiensis.\ud \ud METHODS\ud \ud Four treatment regimens were investigated: blood fed three days before PPF exposure (A), blood fed one day before PPF exposure (B), blood fed one day after PPF exposure (C) and blood fed three days after PPF exposure (D) for their impact on egg laying (fecundity) and the production of viable offspring (fertility), while the impact of PPF exposure on mosquito survival was investigated in the absence of a blood meal. All regimens and the survival study exposed mosquitoes to PPF via the bottle assay at 3mg AI/m2 for 30 minutes.\ud \ud RESULTS\ud \ud Female mosquitoes that blood-fed one day prior to PPF exposure (regimen B), produced no viable offspring during that gonotrophic cycle (100% reduction in fertility). All other treatments had no significant effect. The observed reductions in fecundity and fertility were caused by the retention of eggs (97% of eggs retained, i.e. produced in the ovaries but not laid, in regimen B, p = 0.0004). Some of these retained eggs were deformed in shape. PPF exposure on mosquito survival in the absence of a blood meal was found to have no effect.\ud \ud CONCLUSIONS\ud \ud The results presented here suggest that sterilising adult malaria vectors using PPF could form part of a malaria control strategy, taking advantage of the lack of reported resistance to PPF in mosquitoes and its unique mode of action. We propose that targeting resting mosquitoes, which are highly susceptible to PPF at low doses, is the optimal direction for developing this control tool.

Background\ud \ud The suppression of indoor malaria transmission requires additional interventions that complement the use of insecticide treated nets (ITNs) and indoor residual spraying (IRS). Previous studies have examined the impact of house structure on malaria transmission in areas of low transmission. This study was conducted in a high transmission setting and presents further evidence about the association between specific house characteristics and the abundance of endophilic malaria vectors.\ud \ud Methods\ud \ud Mosquitoes were sampled using CDC light traps from 72 randomly selected houses in two villages on a monthly basis from 2008 to 2011 in rural Southern Tanzania. Generalized linear models using Poisson distributions were used to analyze the association of house characteristics (eave gaps, wall types, roof types, number of windows, rooms and doors, window screens, house size), number of occupants and ITN usage with mean catches of malaria vectors (An.gambiae s.l. and An. funestus).\ud \ud Results\ud \ud A total of 36490 female An. gambiae s.l. were collected in Namwawala village and 21266 in Idete village. As for An. funestus females, 2268 were collected in Namwawala and 3398 in Idete. Individually, each house factor had a statistically significant impact (p