For schistosomiasis it is firmly established that the probability of infection increases with increasing proximity to an infectious water source which might explain this decline as households are located further away from water collection points on the northern shoreline.19 and 25 However, for malaria it could point

towards a density dependant effect where transmission is highest amongst people who live in closest proximity to one another.17 and 26 Having the position of the households allows investigations of other factors which might locally perturb the occurrence of infections, Gemcitabine molecular weight as well as control interventions that are set in place to diminish them.27 For example, 97.6% of our study cohort reported having recently accessed local health services. Interestingly, 23.6% of mothers reported having to walk for less than one hour with the remaining CH5424802 concentration study population having to walk for 1–4 hours. General access to medications was reasonable and across the village 76% reported having a bednet in their household, with just over half of these reporting it was insecticide treated. We are yet to plot distribution of these bednets across the village but their presence could potentially mitigate the transmission dynamics of anopheline mosquitoes within Bukoba.27 For hookworm, only a quarter of our cohort reported regularly wearing sandals, a well-known factor protecting against infection.6 It is clear that

knowing the location of households enables a new level of geospatial modelling and investigation of risk factors across an examined cohort. As we follow the infection dynamics of these three diseases through time it could also provide new spatial insights into longitudinal processes.28 Previous work has shown that in the context of host morbidity knowing the spatial co-occurrence of malaria and schistosomiasis is very important.13 and 14 The on-the-ground accuracy of these units was very good, equivalent to the Oregon 550t unit which is currently tenfold higher in price. However, the Oregon 550t is able to take ‘geostamped’ digital images which is particularly Clomifene useful

as an aide memoire for specific visual points of interest, for example, conditions at each household such as grass thatching or metal roofing, or at points along the way such as small water bodies or agricultural land use.20 Most importantly these images can also be uploaded onto GoogleEarth and geospatially aligned to further augment the visual information apparent from the background satellite image. A number of our GPS units malfunctioned in the field some of which resulted in the loss of captured data upon download (eight households). We speculate that the majority of the malfunctions were the result of insufficiently robust hardware for field conditions, often compromising the ability to synchronise with satellites due to humidity and/or water exposure, or due to poor quality software (a common error was the software failing to recognise the device).