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BACKGROUND: Household air pollution (HAP) from biomass fuel combustion remains a leading environmental risk factor for morbidity worldwide. OBJECTIVE: Measure the effect of liquefied petroleum gas (LPG) interventions on HAP exposures in Puno, Peru. METHODS: We conducted a 1-y randomized controlled trial followed by a 1-y pragmatic crossover trial in 180 women age 25-64 y. During the first year, intervention participants received a free LPG stove, continuous fuel delivery, and regular behavioral messaging, whereas controls continued their biomass cooking practices. During the second year, control participants received a free LPG stove, regular behavioral messaging, and vouchers to obtain LPG tanks from a nearby distributor, whereas fuel distribution stopped for intervention participants. We collected 48-h kitchen area concentrations and personal exposures to fine particulate matter (PM) with aerodynamic diameter ≤ 2.5 µm (PM 2.5), black carbon (BC), and carbon monoxide (CO) at baseline and 3-, 6-, 12-, 18-, and 24-months post randomization. RESULTS. Baseline mean ± standard deviation (SD) PM2.5 (kitchen area concentrations 1,220 ± 1,010 vs. 1,190 ± 880 µg/m³; personal exposure 126 ± 214 vs. 104 ± 100 µg/m³), CO (kitchen 53 ± 49 vs. 50 ± 41 ppm; personal 7 ± 8 vs. 7 ± 8 ppm), and BC (kitchen 180 ± 120 vs. 210 ± 150 µg/m³; personal 19 ± 16 vs. 21 ± 22 µg/m³) were similar between control and intervention participants. Intervention participants had consistently lower mean (± SD) concentrations at the 12-month visit for kitchen (41 ± 59 µg/m³, 3±6 µg/m³, and 8 ± 13 ppm) and personal exposures (26 ± 34 µg/m³, 2±3 µg/m³, and 3 ± 4 ppm) to PM2.5, BC, and CO when compared to controls during the first year. In the second year, we observed comparable HAP reductions among controls after the voucher-based intervention for LPG fuel was implemented (24-month visit PM2.5, BC, and CO kitchen mean concentrations of 34 ± 74 µg/m³,3±5 µg/m³, and 6 ± 6 ppm and personal exposures of 17 ± 15 µg/m³,2±2 µg/m³, and 3 ± 4 ppm, respectively), and average reductions were present among intervention participants even after free fuel distribution stopped (24-month visit PM2.5, BC, and CO kitchen mean concentrations of 561 ± 1,251 µg/m³, 82 ± 124 µg/m³, and 23 ± 28 ppm and personal exposures of 35 ± 38 µg/m³,6±6 µg/m³, and 4 ± 5 ppm, respectively). DISCUSSION: Both home delivery and voucher-based provision of free LPG over a 1-y period, in combination with provision of a free LPG stove and longitudinal behavioral messaging, reduced HAP to levels below 24-h World Health Organization air quality guidelines. Moreover, the effects of the intervention on HAP persisted for a year after fuel delivery stopped. Such strategies could be applied in LPG programs to reduce HAP and potentially improve health. [ABSTRACT FROM AUTHOR]

Rationale: Approximately 40% of people worldwide are exposed to household air pollution (HAP) from the burning of biomass fuels. Previous efforts to document health benefits of HAP mitigation have been stymied by an inability to lower emissions to target levels. Objectives: We sought to determine if a household air pollution intervention with liquefied petroleum gas (LPG) improved cardiopulmonary health outcomes in adult women living in a resource-poor setting in Peru. Methods: We conducted a randomized controlled field trial in 180 women aged 25-64 years living in rural Puno, Peru. Intervention women received an LPG stove, continuous fuel delivery for 1 year, education, and behavioral messaging, whereas control women were asked to continue their usual cooking practices. We assessed for stove use adherence using temperature loggers installed in both LPG and biomass stoves of intervention households. Measurements and Main Results: We measured blood pressure, peak expiratory flow (PEF), and respiratory symptoms using the St. George's Respiratory Questionnaire at baseline and at 3-4 visits after randomization. Intervention women used their LPG stove exclusively for 98% of days. We did not find differences in average postrandomization systolic blood pressure (intervention - control 0.7 mm Hg; 95% confidence interval, -2.1 to 3.4), diastolic blood pressure (0.3 mm Hg; -1.5 to 2.0), prebronchodilator peak expiratory flow/height2 (0.14 L/s/m2; -0.02 to 0.29), postbronchodilator peak expiratory flow/height2 (0.11 L/s/m2; -0.05 to 0.27), or St. George's Respiratory Questionnaire total score (-1.4; -3.9 to 1.2) over 1 year in intention-to-treat analysis. There were no reported harms related to the intervention. Conclusions: We did not find evidence of a difference in blood pressure, lung function, or respiratory symptoms during the year-long intervention with LPG. Clinical trial registered with www.clinicaltrials.gov (NCT02994680). [ABSTRACT FROM AUTHOR]

Background Norovirus is a leading cause of acute gastroenteritis worldwide, yet there is limited information on homotypic or heterotypic protection following natural infection to guide vaccine development. Methods A total of 6020 stools collected from 299 Peruvian children between 2010 and 2014 were tested by norovirus real-time reverse-transcription polymerase chain reaction followed by sequence-based genotyping. Cox proportional hazards models were used to derive adjusted hazard ratios (HRs) of infection among children with vs without prior exposure. Results Norovirus was detected in 1288 (21.3%) samples. GII.4 (26%), GII.6 (19%), and GI.3 (9%) viruses accounted for 54% of infections. Homotypic protection for GI.3 (HR, 0.35; P  = .015), GI.7 (HR, 0.19; P  = .022), GII.4 (HR, 0.39; P  < .001), and GII.6 (HR, 0.52; P  = .006) infections was observed. Hazard analysis showed that children with prior GII.4 infection exhibited heterotypic protection with a 48% reduction of subsequent GI.3 infection (HR, 0.52; P  = .005). Prior exposure to GI.3, GII.2, and GII.17 infections enhanced susceptibility to subsequent infections with several other norovirus genotypes. Conclusions Children up to 2 years of age infected with GII.4 noroviruses demonstrated both homotypic and heterotypic protection to reinfection with other genotypes. These data support the need for ongoing vaccine development efforts with GII.4 as the main component and caution the inclusion of genotypes that may enhance susceptibility to infections. [ABSTRACT FROM AUTHOR]

Reducing the burden of household air pollution could be achieved with exclusive adoption of cleaner fuels such as liquefied petroleum gas (LPG). However, we lack understanding of how much LPG is required to support exclusive use and how household characteristics affect this quantity. This paper used data from 90 participants in the Cardiopulmonary outcomes and Household Air Pollution (CHAP) trial in Puno, Peru who received free LPG deliveries for one year. Households with a mean of four members that cooked nearly exclusively (>98%) with LPG used an average of 19.1 kg (95% CI 18.5 to 19.6) of LPG per month for tasks similar to those done with the traditional biomass stove. LPG use per month was 0.5 kg higher for each additional pig or dog owned (p = 0.003), 0.7 kg higher for each additional household member (p < 0.001), 0.3 kg higher for households in the second-lowest compared to the lowest wealth quintile (p = 0.01), and 1.1 kg higher if the household had previously received subsidized LPG (p = 0.05). LPG use per month was 1.1 kg lower during the rainy season (p < 0.001) and 1.7 kg lower during the planting season (p < 0.001) compared to the cold and harvest seasons, despite the fact that LPG was not typically used for space heating. LPG use decreased by 0.05 kg per month over the course of one year after receiving the LPG stove (p = 0.02). These results suggest that achieving exclusive LPG use in Puno, Peru requires that rural residents have affordable access to an average of two 10 kg LPG tanks per month. Conducting similar investigations in other countries could help policymakers set and target LPG subsidies to ensure that households have access to enough LPG to achieve exclusive LPG use and the potential health benefits. • Study participants in Puno used on average 19.1 kg of LPG per month. • LPG use was greater with pig/dog ownership, wealth, family size, and LPG vouchers. • Participants used LPG and biomass similarly, but more often prepared lunch with LPG. • The current subsidy in Peru covers only 25% of rural residents' LPG needs. • Programs must provide enough fuel for exclusive use to achieve potential benefits. [ABSTRACT FROM AUTHOR]

Background: The prediction of future obesity patterns is crucial for effective strategic planning. However, disproportionally changing body mass index (BMI) distributions pose particular challenges. Flexible modelling of the shape of BMI distributions may improve prediction performance.Methods: We used data from repeated national health surveys conducted in Mexico, Colombia and Peru at four or five time points between 1988 and 2014. Data from all surveys except the last survey were used to construct prediction models for three obesity indicators (median BMI, overweight/obesity prevalence and obesity prevalence) for the time of the last survey. We assessed their performance using predicted curves, absolute prediction errors and comparison of actual and predicted distributions. With one method, we modelled the shape of BMI distributions assuming BMI follows a Box-Cox Power Exponential (BCPE) distribution, whose parameters were modelled as a function of interval or nominal 5-year age groups, time and their interaction terms. In a second method, we modelled each of the obesity indicators directly as a function of the same covariates using quantile and logistic regression.Results: The BCPE model with interval age groups yielded the best prediction performance in predicting obesity prevalence. Average absolute prediction errors across all age groups were 4.3 percentage points (95% percentile interval: 1.9, 7.5), 2.5 (1.2, 6.1) and 1.7 (1.0, 9.3), with data from Mexico, Colombia and Peru, respectively. This superiority was weak or none for overweight/obesity prevalence and median BMI.Conclusion: The BCPE model performed better for prediction of the extremes of BMI distribution, possibly by incorporating its shape more precisely. [ABSTRACT FROM AUTHOR]

Environmental enteric dysfunction (EED) is associated with chronic undernutrition. Efforts to identify minimally invasive biomarkers of EED reveal an expanding number of candidate analytes. An analytic strategy is reported to select among candidate biomarkers and systematically express the strength of each marker's association with linear growth in infancy and early childhood. 180 analytes were quantified in fecal, urine and plasma samples taken at 7, 15 and 24 months of age from 258 subjects in a birth cohort in Peru. Treating the subjects' length-for-age Z-score (LAZ-score) over a 2-month lag as the outcome, penalized linear regression models with different shrinkage methods were fitted to determine the best-fitting subset. These were then included with covariates in linear regression models to obtain estimates of each biomarker's adjusted effect on growth. Transferrin had the largest and most statistically significant adjusted effect on short-term linear growth as measured by LAZ-score–a coefficient value of 0.50 (0.24, 0.75) for each log2 increase in plasma transferrin concentration. Other biomarkers with large effect size estimates included adiponectin, arginine, growth hormone, proline and serum amyloid P-component. The selected subset explained up to 23.0% of the variability in LAZ-score. Penalized regression modeling approaches can be used to select subsets from large panels of candidate biomarkers of EED. There is a need to systematically express the strength of association of biomarkers with linear growth or other outcomes to compare results across studies. Author summary: Childhood undernutrition is widespread throughout the world and has severe, long-lasting health impacts. Substances measured in blood, urine and stool could be used as biomarkers to identify children undergoing growth failure before these impacts occur. However, it is not yet known which of the many markers that can be identified are accurate and clinically useful predictors of poor growth in infants and children. This study used a large number of candidate biomarkers of immune activation, metabolism and hormones and applied statistical methods to narrow them down from 110 different substances, to the 36 best predictors of growth in 258 Peruvian infants. It also estimated how large the effect of each of these markers was on height two months later. The biomarker with the largest effect was transferrin, a glycoprotein that can be measured in blood samples. 15-month old children with elevated transferrin were around two thirds of a centimeter taller on average at 17 months than those with low levels. Transferrin and other proteins, glycoproteins, hormones and antibodies that this study identified, can be measured easily and affordably in standard laboratories making them feasible to be used broadly as prognostic markers as part of child health and nutrition programs in under-resourced settings. [ABSTRACT FROM AUTHOR]

Objective: Unequal obesity distributions among adult populations have been reported in low- and middle-income countries, but mainly based on data of women of reproductive age. Moreover, incorporation of ever-changing skewed BMI distributions in analyses has been a challenge. Our study aimed to assess magnitude and rates of change in BMI distributions by age and sex. Design: Shapes of BMI distributions were estimated for 2005 and 2010, and their changes were assessed, using the generalized additive model for location, scale and shape (GAMLSS) and assuming BMI follows a Box–Cox power exponential (BCPE) distribution. Setting: Nationally representative, repeated cross-sectional health surveys conducted between 2005 and 2013 in Mexico, Colombia and Peru. Subjects: Adult men and non-pregnant women aged 20–69 years. Results: Whereas women had more right-shifted and wider BMI distributions than men in almost all age groups across the countries in 2010, men in their 30s–40s experienced more rapid increases in BMI between 2005 and 2010, notably in Peru. The highest increase in overweight and obesity prevalence was observed among Peruvian men of 35–39 years, with a 5-year increase of 21 percentage points. Conclusions: The BCPE–GAMLSS method is an alternative to analyse measurements with time-varying distributions visually, in addition to conventional indicators such as means and prevalences. Consideration of differences in BMI distributions and their changes by sex and age would provide vital information in tailoring relevant policies and programmes to reach target populations effectively. Increases in BMI portend increases of obesity-associated diseases, for which preventive and preparative actions are urgent. [ABSTRACT FROM AUTHOR]

Background: Environmental enteropathy (EE) impairs the gut's absorptive capacity and immune function and causes decelerations in statural growth that manifest gradually over time. Objective: To illustrate an approach for assessing emerging biomarkers of EE, we separately assessed the associations between 3 such markers and subsequent nutritional status. Design: Stool samples were routinely collected between January 2010 and November 2014 from a cohort of 303 Peruvian infants and analyzed for concentrations of the biomarkers a-1-antitrypsin (AAT), myeloperoxidase, and neopterin. For each marker, a mixed-effects linear regression model was fitted for length-forage z scores (LAZs) obtained from anthropometric assessments that incorporated covariate predictors, polynomial terms for age, and product interaction terms to test associations over varying lag lengths. The biomarkers' contribution to the models was assessed with the use of the likelihood ratio test and partial R2 statistics. Results: Test statistics for the combined inclusion of the 4-model terms that involved the biomarker were highly statistically significant for AAT (28.71; P, 0.0001) and myeloperoxidase (62.79; P, 0.0001) over a 3-mo lag and moderately so for neopterin (13.97; P = 0.0074). AAT and myeloperoxidase seemed to interact strongly with age, with the magnitude and direction of the effect varying considerably over the first 3 y of life. The largest proportion of the variance explained by any biomarker (2.8%) and the largest difference in LAZ predicted between the 5th and 95th percentile (0.25) was by myeloperoxidase over a 2-mo lag. Conclusions: Of the 3 fecal biomarkers studied, 2 that related to intestinal function--AAT and myeloperoxidase--were associated with small but highly statistically significant differences in future statural growth trajectories in infants in this cohort, lending further evidence to the EE hypothesis that increased gut permeability and inflammation adversely affects subsequent nutritional status. This association exhibited a complex interaction with age. This trial was registered at clinicaltrials.gov as NCT02441426. [ABSTRACT FROM AUTHOR]

Household air pollution (HAP) from combustion of biomass fuel, such as wood and animal dung, is among the leading environmental risk factors for preventable disease. Close to half of the world's population relies on biomass cookstoves for their daily cooking needs. Understanding factors that affect HAP can inform measures to maximize the effectiveness of cookstove interventions in a cost-effective manner. However, the impact of kitchen and household characteristics, as well as the presence of secondary stoves, on HAP concentrations is poorly understood in Puno, Peru. To explore how household characteristics explain variability of kitchen area concentrations and personal exposures to CO, PM 2.5 and BC from biomass cookstoves among women in rural Peru. Household characteristics (including kitchen materials and layout, wealth, and cooking behaviors) and HAP measurements were collected from 180 households in Puno, Peru, from baseline measurements of a randomized trial. Kitchen area concentrations and personal exposures to carbon monoxide (CO), fine particulate matter (PM 2.5) and black carbon (BC) were sampled for 48 h. We implemented simple and multivariable linear regression models to determine the associations between household characteristics and both kitchen area concentration and personal exposure to each pollutant. Mean daily kitchen area concentrations and personal exposures to HAP were, on average, 48 times above World Health Organization indoor guidelines for PM 2.5. We found that roof type explained the most variability in HAP and was strongly associated with both kitchen area concentrations and personal exposures for all pollutants after adjusting for other household variables. Personal exposures were 27%–36% lower for PM 2.5 , CO and BC, in households with corrugated metal roofs, compared to roofs made of natural materials (straw, totora or reed) after adjusting for other factors. Higher kitchen area concentrations were also associated with less wealth, owning more animals, or sampling during the dry season in multivariable models. Having a liquefied petroleum gas (LPG) stove and having a chimney were associated with lower personal exposures, but were not associated with kitchen area concentrations. Personal exposures were lower by 21% for PM 2.5 and 28% for CO and BC concentrations among participants who had both LPG and biomass stoves compared to those with only biomass cookstoves adjusting for other household factors. Characterizing HAP within different settings can help identify effective and culturally-relevant solutions to reduce HAP exposures. We found that housing roof type is strongly related to kitchen area concentrations and personal exposures to HAP, perhaps because of greater ventilation in kitchens with metal roofs compared to those with thatch roofs. Although HAP concentrations remained above guidelines for all households, promoting use of metal roof materials and LPG stoves may be actionable interventions that can help reduce exposures to HAP in high-altitude rural Peru and similar settings. • Kitchen concentrations in Puno were, on average, 48 times the PM 2.5 recommended levels. • Kitchens with metal roofs had 50% lower PM 2.5 compared to straw and reed roofs. • Women who owned LPG stoves had 21% lower personal exposures to PM 2.5. • Personal exposures to PM 2.5 were 35% lower in kitchens with a chimney. • LPG stoves and ventilation provided by metal roofs reduce personal exposures to HAP. [ABSTRACT FROM AUTHOR]

Background: Enterotoxigenic E. coli (ETEC) is a leading cause of diarrheal morbidity and mortality in children, although the data on disease burden, epidemiology, and impact on health at the community level are limited., Methods: In a longitudinal birth cohort study of 345 children followed until 24 months of age in Lima, Peru, we measured ETEC burden in diarrheal and non-diarrheal samples using quantitative PCR (LT, STh, and STp toxin genes), studied epidemiology and measured anthropometry in children., Results: About 70% of children suffered from one or more ETEC diarrhea episodes. Overall, the ETEC incidence rate (IR) was 73 per 100 child-years. ETEC infections began early after birth causing 10% (8.9-11.1) ETEC-attributable diarrheal burden at the population level (PAF) in neonates and most of the infections (58%) were attributed to ST-ETEC [PAF 7.9% (1.9-13.5)] and LT + ST-ETEC (29%) of which all the episodes were associated with diarrhea. ETEC infections increased with age, peaking at 17% PAF (4.6-27.7%; p  = 0.026) at 21 to 24 months. ST-ETEC was the most prevalent type (IR 32.1) with frequent serial infections in a child. The common colonization factors in ETEC diarrhea cases were CFA/I, CS12, CS21, CS3, and CS6, while in asymptomatic ETEC cases were CS12, CS6 and CS21. Only few (5.7%) children had repeated infections with the same combination of ETEC toxin(s) and CFs, suggested genotype-specific immunity from each infection. For an average ETEC diarrhea episode of 5 days, reductions of 0.060 weight-for-length z-score (0.007 to 0.114; p  = 0.027) and 0.061 weight-for-age z-score (0.015 to 0.108; p  = 0.009) were noted in the following 30 days., Conclusion: This study showed that ETEC is a significant pathogen in Peruvian children who experience serial infections with multiple age-specific pathotypes, resulting in transitory growth impairment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer DS declared a shared affiliation with the author MS to the handling editor at the time of review. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Pajuelo, Noazin, Cabrera, Toledo, Velagic, Arias, Ochoa, Moulton, Saito, Gilman and Chakraborty.)

Most children with autism spectrum disorder (ASD), in resource-limited settings (RLS), are diagnosed after the age of four. Our work confirmed and extended results of Pierce that eye tracking could discriminate between typically developing (TD) children and those with ASD. We demonstrated the initial 15 s was at least as discriminating as the entire video. We evaluated the GP-MCHAT-R, which combines the first 15 s of manually-coded gaze preference (GP) video with M-CHAT-R results on 73 TD children and 28 children with ASD, 36-99 months of age. The GP-MCHAT-R (AUC = 0.89 (95%CI: 0.82-0.95)), performed significantly better than the MCHAT-R (AUC = 0.78 (95%CI: 0.71-0.85)) and gaze preference (AUC = 0.76 (95%CI: 0.64-0.88)) alone. This tool may enable early screening for ASD in RLS.

Background: Detrimental effects of diarrhea on child growth and survival are well documented, but details of the underlying mechanisms remain poorly understood. Recent evidence demonstrates that perturbations to normal development of the gut microbiota in early life may contribute to growth faltering and susceptibility to related childhood diseases. We assessed associations between diarrhea, gut microbiota configuration, and childhood growth in the Peruvian Amazon., Methods: Growth, diarrhea incidence, illness, pathogen infection, and antibiotic exposure were assessed monthly in a birth cohort of 271 children aged 0-24 months. Gut bacterial diversity and abundances of specific bacterial taxa were quantified by sequencing 16S rRNA genes in fecal samples collected at 6, 12, 18, and 24 months. Linear and generalized linear models were used to determine whether diarrhea was associated with altered microbiota and, in turn, if features of the microbiota were associated with the subsequent risk of diarrhea., Results: Diarrheal frequency, duration, and severity were negatively associated with bacterial diversity and richness (P < .05). Children born stunted (length-for-age z-score [LAZ] ≤ -2) who were also severely stunted (LAZ ≤ -3) at the time of sampling exhibited the greatest degree of diarrhea-associated reductions in bacterial diversity and the slowest recovery of bacterial diversity after episodes of diarrhea. Increased bacterial diversity was predictive of reduced subsequent diarrhea from age 6 to 18 months., Conclusions: Persistent, severe growth faltering may reduce the gut microbiota's resistance and resilience to diarrhea, leading to greater losses of diversity and longer recovery times. This phenotype, in turn, denotes an increased risk of future diarrheal disease and growth faltering., (© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background: Campylobacter infection is associated with impaired growth of children, even in the absence of symptoms. To examine the underlying mechanisms, we evaluated associations between Campylobacter infection, linear growth, and fecal microbial community features in a prospective birth cohort of 271 children with a high burden of diarrhea and stunting in the Amazonian lowlands of Peru., Methods: Campylobacter was identified using a broadly reactive, genus-specific enzyme-linked immunosorbent assay. 16S rRNA-based analyses were used to identify bacterial taxa in fecal samples at ages 6, 12, 18, and 24 months (N = 928). Associations between infection, growth, and gut microbial community composition were investigated using multiple linear regression adjusting for within-child correlations, age, and breastfeeding. Indicator species analyses identified taxa specifically associated with Campylobacter burden., Results: Ninety-three percent (251) of children had Campylobacter present in asymptomatic fecal samples during the follow-up period. A 10% increase in the proportion of stools infected was associated with mean reductions of 0.02 length-for-age z scores (LAZ) at 3, 6, and 9 months thereafter (P < .01). We identified 13 bacterial taxa indicative of cumulative Campylobacter burden and 14 taxa significantly associated with high or low burden of enteroaggregative Escherichia coli, norovirus, or Giardia., Conclusions: Campylobacter infection is common in this cohort and associated with changes in microbial community composition. These results support the notion that disruptions to the fecal microbiota may help explain the observed effects of asymptomatic infections on growth in early life., (© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America.)

Background/objectives: Previous studies about obesity and its associated factors in low- and middle-income countries have been based mostly on women of reproductive age. Furthermore, disproportionally changing BMI distributions have been a challenge for its appropriate modeling. In this context, we assessed the magnitude and rate of change in BMI distribution by socioeconomic and geographic factors in both sexes in Latin American countries, modeling the shape of BMI distributions., Subjects/methods: We used data from national surveys conducted in Mexico, Colombia, and Peru at two time points between 2005 and 2013 (N = 57,414, 13,5403, and 30,811, respectively). We estimated shapes of BMI distributions for 2005 and 2010, and assessed their changes, using the generalized additive model for location, scale, and shape (GAMLSS), in which BMI was assumed to follow a Box-Cox Power Exponential (BCPE) distribution., Results: In all the three countries, higher education was negatively associated with BMI in women but somewhat positive in men; and household wealth was positively associated in men but not in women. Lower household wealth was associated with higher rates of change in BMI distributions in women., Conclusion: Education and household wealth were associated with BMI distributions and their change over time. Observed sex differences in these associations have implications for designing relevant policies and programs to approach target populations effectively. The BCPE-GAMLSS method can provide a useful visual assessment of time-varying measures.

Background: Climate change threatens to undermine recent progress in reducing global deaths from diarrhoeal disease in children. However, the scarcity of evidence about how individual environmental factors affect transmission of specific pathogens makes prediction of trends under different climate scenarios challenging. We aimed to model associations between daily estimates of a suite of hydrometeorological variables and rotavirus infection status ascertained through community-based surveillance., Methods: For this analysis of multisite cohort data, rotavirus infection status was ascertained through community-based surveillance of infants in the eight-site MAL-ED cohort study, and matched by date with earth observation estimates of nine hydrometeorological variables from the Global Land Data Assimilation System: daily total precipitation volume (mm), daily total surface runoff (mm), surface pressure (mbar), wind speed (m/s), relative humidity (%), soil moisture (%), solar radiation (W/m 2 ), specific humidity (kg/kg), and average daily temperatures (°C). Lag relationships, independent effects, and interactions were characterised by use of modified Poisson models and compared with and without adjustment for seasonality and between-site variation. Final models were created with stepwise selection of main effects and interactions and their validity assessed by excluding each site in turn and calculating Tjur's Coefficients of Determination., Findings: All nine hydrometeorological variables were significantly associated with rotavirus infection after adjusting for seasonality and between-site variation over multiple consecutive or non-consecutive lags, showing complex, often non-linear associations that differed by symptom status and showed considerable mutual interaction. The final models explained 5·9% to 6·2% of the variability in rotavirus infection in the pooled data and their predictions explained between 0·0% and 14·1% of the variability at individual study sites., Interpretation: These results suggest that the effect of climate on rotavirus transmission was mediated by four independent mechanisms: waterborne dispersal, airborne dispersal, virus survival on soil and surfaces, and host factors. Earth observation data products available at a global scale and at subdaily resolution can be combined with longitudinal surveillance data to test hypotheses about routes and drivers of transmission but showed little potential for making predictions in this setting., Funding: Bill & Melinda Gates Foundation; Foundation for the National Institutes of Health, National Institutes of Health, Fogarty International Center; Sherrilyn and Ken Fisher Center for Environmental Infectious Diseases, Johns Hopkins School of Medicine; and NASA's Group on Earth Observations Work Programme., (Copyright © 2019 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

The pork tapeworm, Taenia solium , is among the leading causes of preventable epilepsy in the world and is common in rural areas of developing countries where sanitation is limited and pigs have access to human feces. Prior studies in rural villages of Peru have observed clusters of T. solium cysticercosis among pigs that live near human tapeworm carriers. Such spatial analyses, however, have been limited by incomplete participation and substandard diagnostic tests. In this study, we evaluated the association between necropsy-confirmed cysticercosis in pigs and their distance to T. solium tapeworm carriers in six villages in northern Peru. A total of six (1.4%) tapeworm carriers were detected using copro-antigen enzyme-linked immunosorbent assay and seven of 10 (70%) pigs belonging to the tapeworm carriers were found with viable cyst infection on necropsy. This was significantly greater than the prevalence of viable cyst infection among pigs living < 500 m (11%) and > 500 m (0.5%) from a tapeworm carrier ( P < 0.001 for distance trend). Similar statistically significant prevalence gradients were observed after adjustment for possible confounders and for other pig-level outcomes including infection with > 10 viable cysts, degenerated cyst infection, and serological outcomes. This investigation confirms that porcine cysticercosis clusters strongly around tapeworm carriers in endemic rural regions of northern Peru and supports interventions that target these hotspots.

Few studies have examined the influence of individual-, household-, and community-scale risk factors on carriage of resistant commensal bacteria. We determined children's medical, agricultural, and environmental exposures by household, pharmacy, and health facility surveys and Escherichia coli cultures of children, mothers' hands, household animals, and market chickens in Peru. Among 522 children with a positive stool culture, by log-binomial regression, using "any antibiotic" and 1-14 (versus 0) sulfa doses in the past 3 months increased children's risk, respectively, for ampicillin- and sulfamethoxazole-resistant E. coli carriage (P = 0.01-0.02). Each household member taking "any antibiotic" increased children's risk for sulfamethoxazole- and multidrug-resistant E. coli carriage (P < 0.0001). Residence in a zone where a larger proportion of households served home-raised chicken (as contrasted with intensively antibiotic-raised market chicken) protected against carrying E. coli resistant to all drugs (P = 0.0004-0.04). Environmental contamination with drug-resistant bacteria appeared to significantly contribute to children's carriage of antibiotic-resistant E. coli.

Background: Neurocysticercosis accounts for 30%-50% of all late-onset epilepsy in endemic countries. We assessed the clustering patterns of Taenia solium human cysticercosis seropositivity and seizures around tapeworm carriers in seven rural communities in Peru., Methodology: The presence of T. solium-specific antibodies was defined as one or more positive bands in the enzyme-linked immunoelectrotransfer blot (EITB). Neurocysticercosis-related seizures cases were diagnosed clinically and had positive neuroimaging or EITB., Principal Findings: Eleven tapeworm carriers were identified by stool microscopy. The seroprevalence of human cysticercosis was 24% (196/803). Seroprevalence was 21% >50 m from a carrier and increased to 32% at 1-50 m (p = 0.047), and from that distance seroprevalence had another significant increase to 64% at the homes of carriers (p = 0.004). Seizure prevalence was 3.0% (25/837) but there were no differences between any pair of distance ranges (p = 0.629, Wald test 2 degrees of freedom)., Conclusion/significance: We observed a significant human cysticercosis seroprevalence gradient surrounding current tapeworm carriers, although cysticercosis-related seizures did not cluster around carriers. Due to differences in the timing of the two outcomes, seroprevalence may reflect recent T. solium exposure more accurately than seizure frequency.

We estimated the Taenia solium swine cysticercosis risk gradient surrounding tapeworm carriers in seven rural communities in Peru. At baseline, the prevalences of taeniasis by microscopy and swine cysticercosis by serology were 1.2% (11 of 898) and 30.8% (280 of 908), respectively. The four-month cumulative seroincidence was 9.8% (30 of 307). The unadjusted swine seroprevalence and seroincidence rates increased exponentially by 12.0% (95% confidence [CI] = 9.7-14.3%) and 32.8% (95% CI = 25.0-41.0%), respectively when distance to carriers decreased by half. Swine seroprevalence was 18.4% at > 500 meters from a carrier, 36.5% between 51 and 500 meters, and 68.9% within 50 meters (P < 0.001). Swine seroincidence also displayed a strong gradient near tapeworm carriers (3.8%, 12.2%, and 44.0%; P < 0.001). Within 50 meters, swine seroprevalence appeared unaffected if the owners harbored tapeworms, although pigs owned by a tapeworm carrier had a four times higher seroincidence compared with other pigs (P = 0.005). In rural areas, swine cysticercosis occurs in high-risk hotspots around carriers where control interventions could be delivered.

Background: Inadequate water and sanitation adversely affect the health of children in developing countries. We aimed to assess the effects of water and sanitation on childhood health in a birth cohort of Peruvian children., Methods: We followed up children once a day for diarrhoea and once a month for anthropometry, and obtained data for household water and sanitation at baseline., Findings: At 24 months of age, children with the worst conditions for water source, water storage, and sanitation were 1.0 cm (95% CI 0.1-0.8) shorter and had 54% (-1 to 240) more diarrhoeal episodes than did those with the best conditions. Children from households with small storage containers had 28% (1-63) more diarrhoeal episodes than did children from households with large containers. Lack of adequate sewage disposal explained a height deficit of 0.9 cm (0.2-1.7) at 24 months of age. Better water source alone did not accomplish full health benefits. In 24-month-old children from households with a water connection, those in households without adequate sewage disposal and with small storage containers were 1.8 cm (0.1-3.6) shorter than children in households with sewage and with large storage containers., Interpretation: Our findings show that nutritional status is a useful endpoint for water and sanitation interventions and underscores the need to improve sanitation in developing countries. Improved and more reliable water sources should discourage water storage at risk of becoming contaminated, decrease diarrhoeal incidence, and improve linear growth in children.

The prevalence and characteristics of human taeniasis/cysticercosis and porcine cysticercosis were assessed in an endemic area of the Peruvian highlands. Individuals from 10 communities had stool examinations (N = 2,951) and serologic testing for Taenia solium antibodies (N = 2,583). The total porcine population present (N = 703) was also examined by serology. Cysticercosis is hyperendemic in this area and is associated with an important number of seizure cases. Human seroprevalence by village ranged from 7.1-26.9% (mean, 13.9%). Seroprevalence was higher among individuals with a history of seizures but not in those reporting a history of headache or intestinal taeniasis. Prevalence of taeniasis ranged from 0-6.7% (median, 2.5%). Coproantigen detection found 2.4 times more taeniasis cases than did microscopy (direct and after concentration). Age distribution for taeniasis showed a peak at younger ages than for seroprevalence. Porcine seroprevalence ranged from 42-75%. Random effects logistic regression models for human seropositivity demonstrated both in-house clustering of cases and a large increase in risk associated with a tapeworm carrier in the house. Besides confirming the close relationship between taeniasis and cysticercosis cases, this large-scale field study demonstrated early age of tapeworm and cysticercosis infections in humans, and short duration of taeniasis infections.

Objectives: We conducted a 4-year (1995-1998) field study in a Peruvian peri-urban community (pueblo joven) to examine the relation between diarrhea and nutritional status in 230 children <3 years of age., Methods: We followed the birth cohort daily for diarrhea and monthly for anthropometry. We modeled diarrheal incidence with a multivariate time-to-event regression model to account for multiple episodes per child and irregular follow-up periods and diarrheal duration with a mixed-effects gamma regression model to account for disease heterogeneity across children., Results: During 159,551 child-days of follow-up, we identified 1387 diarrheal episodes, which yielded an average incidence of 3.2 episodes per child-year. Diarrhea was seasonal, for example, infants had up to 8 diarrheal episodes during the summer; however, these variations decreased noticeably with age. Nutritional status was significantly associated with diarrheal incidence. The frequency of diarrhea increased by 15% per standard deviation decrease in height-for-age z score. Diarrheal episodes in children <6 months of age lasted significantly longer than episodes among older children., Conclusions: These results identify infants and children of poor nutritional status as priority risk groups for prevention efforts aimed at reducing the burden of acute childhood diarrhea.