Wong and colleagues have described

Wong and colleagues have described higher densities of in villages than in farming areas and forests, but that mosquito longevity, which is crucial for development, was higher in farming areas and forests. Brant and colleagues have also described a preference of to bite humans at ground level rather than high in the forest canopy. Thus, the likelihood that the main place of transmission occurs outdoors at ground level in forested areas was strongly supported by the findings of Grigg and colleagues, who showed that recent clearing of vegetation was a high-risk activity, as was sleeping outside the house, even though this was relatively infrequent; only 33 (15%) of cases. Recent awareness of the presence of monkeys was also a strong predictor of risk, further suggesting a high likelihood of monkey-to-human transmission as the predominant transmission pathway, rather than human-to-human transmission. This study by Grigg and colleagues provides quantifiable risk estimates for a wide range of variables relevant to the transmission of to humans. There are now a series of studies shedding light on the transmission dynamics of in Sabah, but further research is needed in this area and in other parts of southeast Asia where humans live in the forest or on the forest fringe, sharing their habitat with -infected macaques and their Anopheline vectors. In particular, further research is needed to better understand the ecological interactions that place people at risk of and the measures that can be implemented to minimise these risks. This will also be greatly aided by improving diagnostics and surveillance for this infection so that hot spots of transmission can be rapidly and precisely identified.
Bisphenols are used in the polymerisation of polycarbonate plastics and production of epoxy resins. Bisphenol A (BPA) was first synthesised by Alexander Dianin in 1891, and was considered for use as a pharmaceutical oestrogen for pregnant women, but was not sufficiently potent, and eventually diethylstilbestrol was used instead. Increasing evidence from the past two decades suggest that synthetic chemicals represent an underrecognised third key factor in the obesity epidemic worldwide, alongside diet and physical activity. Bisphenols are one major category of chemicals now recognised as obesogens. Laboratory studies have documented that BPA makes fat Sulindac sulfide bigger and inhibits function of adiponectin. Cross-sectional and longitudinal human studies have also associated BPA exposure with obesity in children and adults. Notably, human studies have not consistently identified the key periods of susceptibility. Differences in results between studies might be the result of leveraging a limited number of spot urine samples in pregnancy as a proxy of exposure. Given that the half-life of BPA is generally 24–48 h, use of a modest number of spot samples introduces exposure imprecision that can influence statistical results. Obesity is not the only concern documented for BPA. Epidemiological studies have identified neurocognitive effects of BPA and newly incident coronary artery disease, and laboratory studies strongly suggest BPA is an ovarian toxicant. The rapidly rising evidence of adverse effects has prompted manufacturers to substitute BPA with various bisphenols (BPS, BPP, BPZ, and BPF, to name a few). These chemicals were not required to be proven as safer alternatives because of the Toxic Substances Control Act, which, until June, 2016, when President Obama signed legislation updating the law, presumed chemicals to be innocent until proven guilty in terms of toxicity in the USA, requiring little toxicity testing data before approval for widespread use by the Environmental Protection Agency. What little we know about one BPA replacement, BPS, suggests serious concerns. BPS has been found to be as oestrogenic in laboratory studies and as toxic to embryos as BPA, and even more persistent in the environment. Is it obesogenic in humans? In , Buyun Liu and colleagues examine data from the 2013–14 National Health and Nutrition Examination Survey to study cross-sectional associations of urinary concentrations of BPA, BPF, and BPS with obesity in adults. Their analysis confirms persistent associations of BPA with obesity, despite lower exposures than previously studied. Although associations of urinary BPF or BPS with body-mass index or obesity were not significant, Liu and colleagues\' analyses raise more questions than answers about whether non-A bisphenols are obesogenic. The authors used statistical models to examine effects of each bisphenol independent of the other; however, no potency data are available to aggregate effects of model relationships in aggregate across the bisphenols, and examination of interactions to evaluate synergy or antagonism were not done. Exposures to BPF and BPS were much lower and less prevalent than BPA and the cross-sectional evaluation of adult obesity is an important limitation of the study design given the known life-course origins, especially early life exposures that can have a big impact on adult obesity. Longitudinal studies are needed, especially to examine pregnancy and early childhood exposures, as are studies that assess the period after the introduction of BPA. Most longitudinal cohort studies of BPA exposure are limited by missing measurements of non-A bisphenols and missing associations could be caused by imprecision in the measurement of bisphenol exposure.