Variation in vectorial capacity for human malaria among Anopheles mosquito species is determined by many factors, including behavior, immunity, and life history. To investigate the genomic basis of vectorial capacity and explore new avenues for vector control, we sequenced the genomes of 16 anopheline mosquito species from diverse locations spanning ~100 million years of evolution. Comparative analyses show faster rates of gene gain and loss, elevated gene shuffling on the X chromosome, and more intron losses, relative to Drosophila. Some determinants of vectorial capacity, such as chemosensory genes, do not show elevated turnover, but instead diversify through protein-sequence changes. This dynamism of anopheline genes and genomes may contribute to their flexible capacity to take advantage of new ecological niches, including adapting to humans as primary hosts.

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Vaccine efficacy and effectiveness (VE) are generally measured as 1 minus some measure of relative risk (RR) in the vaccinated group compared with the unvaccinated group (VE = 1 - RR). In designing a study to evaluate vaccination, the type of effect and the question of interest determine the appropriate choice of comparison population and parameter. Possible questions of interest include that of the biologic effect of vaccination on susceptibility, on infectiousness, or on progression to disease in individuals. The indirect effects, total effects, and overall public health benefits of widespread vaccination of individuals within the context of a vaccination program might also be of primary concern. The change in behavior induced by belief in the protective effects of vaccination might influence the estimates of these effects or might itself be of interest. In this paper, the authors present a framework of study designs that relates the scientific question of interest to the choice of comparison groups, the unit of observation, the level of information available for analysis, and the parameter of effect.

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In 1915, Greenwood and Yule noted that for valid vaccine efficacy studies, exposure to infection in the vaccinated and the unvaccinated must be equal (Proc R Soc Med 1915;8(part 2):113-94). The direct effect of a vaccine, however, needs to be defined by the protection it confers given a specific amount of exposure to infection, not just a comparable exposure. In this paper, two classes of parameters are distinguished along lines differing from the conventional distinction between efficacy and effectiveness. Efficacy parameters attempt to control for exposure to infection and represent direct effects on individuals. Direct effectiveness parameters represent a mixture of direct effects on individuals and indirect effects in the population.

The objective of the study was to test the association between gestational weight gain, reproductive factors, and postpartum weight retention based on a cohort conducted with 405 women aged 18-45 y with follow-up waves at 0.5, 2, 6, and 9 mo postpartum. The outcome variable, postpartum weight retention, was calculated as the difference between the measured weight at each visit minus the prepregnancy weight. We estimated the statistical associations between the outcome variable and potential explanatory covariates of interest by fitting a longitudinal mixed-effects model. Women with gestational weight gain above the recommendations of the Institute of Medicine (IOM) retained significantly more weight than women with weight gain within or below the recommendations, independently of prepregnancy BMI [weight (kg)/height (m(2))] or body fat at baseline. Women with the highest gestational weight gain and with body fat >/=30 g/100 g at baseline had the highest likelihood of developing maternal obesity. The final longitudinal model showed that 35% of each kilogram of weight gained during pregnancy was retained 9 mo postpartum, even after adjustment for age, prepregnancy BMI, body fat at baseline, and years since first parturition. Each unit of increase in prepregnancy BMI was associated with a decrease of -0.51 kg in postpartum weight retention. In conclusion, gestational weight gain was one of the most important predictors for postpartum weight retention and must be monitored systematically with the aim of preventing postpartum obesity and the diseases that follow.