BACKGROUND:Cooking-related biomass smoke is a major source of household air pollution (HAP) and an important health hazard. Prior studies identified associations between HAP exposure and childhood stunting; less is known for underweight and wasting. Few studies had personal HAP measurements. METHODS:557 households in rural Guatemala were enrolled in the CRECER study, the follow-up study of the RESPIRE randomized intervention trial. They were assigned to three groups that received chimney stoves at different ages of the study children. Multiple personal carbon monoxide (CO) exposure measurements were used as proxies for HAP exposures. Children's heights and weights were measured from 24 to 60 months of age. Height-for-age z-score (HAZ), weight-for-age z-score (WAZ), and weight-for-height z-score (WHZ) were calculated based on the World Health Organization's Multicentre Growth Reference Study. HAZ, WAZ, and WHZ below -2 were classified as stunting, underweight, and wasting, respectively. Generalized linear models and mixed effects models were applied. RESULTS:541 children had valid anthropometric data, among whom 488 (90.2 %) were stunted, 192 (35.5 %) were underweight, and 2 (0.3 %) were wasted. A 1 ppm higher average CO exposure was associated with a 0.21 lower HAZ (95 % CI: 0.17-0.25), a 0.13 lower WAZ (95 % CI: 0.10-0.17) and a 0.06 lower WHZ (95 % CI: 0.02-0.10).The associations for HAZ were stronger among boys (coefficient = -0.29, 95 % CI: -0.35 - -0.22) than among girls (coefficient = -0.15, 95 % CI: -0.20 - -0.10). A 1 ppm-year higher cumulative CO exposure was associated with a higher risk of moderate stunting among boys (OR = 1.27, 95 % CI: 1.05-1.59), but not among girls. DISCUSSION:In this rural Guatemalan population, higher HAP exposure was associated with lower HAZ and WAZ. The associations between HAP and HAZ/stunting were stronger among boys. Reducing HAP might benefit childhood somatic growth in rural populations of low-income countries.

Context: Foodborne disease surveillance and outbreak investigations are foundational to the prevention and control of foodborne disease in the United States, where contaminated foods cause an estimated 48 million illnesses, 128 000 hospitalizations, and 3000 deaths each year. Surveillance activities and rapid detection and investigation of foodborne disease outbreaks require a trained and coordinated workforce across epidemiology, environmental health, and laboratory programs. Program: Under the 2011 Food Safety Modernization Act, the Centers for Disease Control and Prevention (CDC) was called on to establish Integrated Food Safety (IFS) Centers of Excellence (CoEs) at state health departments, which would collaborate with academic partners, to identify, implement, and evaluate model practices in foodborne disease surveillance and outbreak response and to serve as a resource for public health professionals. Implementation: CDC designated 5 IFS CoEs in August 2012 in Colorado, Florida, Minnesota, Oregon, and Tennessee; a sixth IFS CoE in New York was added in August 2014. For the August 2019-July 2024 funding period, 5 IFS CoEs were designated in Colorado, Minnesota, New York, Tennessee, and Washington. Each IFS CoE is based at the state health department that partners with at least one academic institution. Evaluation: IFS CoEs have built capacity across public health agencies by increasing the number of workforce development opportunities (developing >70 trainings, tools, and resources), supporting outbreak response activities (responding to >50 requests for outbreak technical assistance annually), mentoring students, and responding to emerging issues, such as changing laboratory methods and the COVID-19 pandemic.

Each year, infections from major foodborne pathogens are responsible for an estimated 9.4 million illnesses, 56,000 hospitalizations, and 1,350 deaths in the United States (1). To evaluate progress toward prevention of enteric infections in the United States, the Foodborne Diseases Active Surveillance Network (FoodNet) conducts surveillance for laboratory-diagnosed infections caused by eight pathogens transmitted commonly through food at 10 U.S. sites. During 2020-2021, FoodNet detected decreases in many infections that were due to behavioral modifications, public health interventions, and changes in health care-seeking and testing practices during the COVID-19 pandemic. This report presents preliminary estimates of pathogen-specific annual incidences during 2022, compared with average annual incidences during 2016-2018, the reference period for the U.S. Department of Health and Human Services' Healthy People 2030 targets (2). Many pandemic interventions ended by 2022, resulting in a resumption of outbreaks, international travel, and other factors leading to enteric infections. During 2022, annual incidences of illnesses caused by the pathogens Campylobacter, Salmonella, Shigella, and Listeria were similar to average annual incidences during 2016-2018; however, incidences of Shiga toxin-producing Escherichia coli (STEC), Yersinia, Vibrio, and Cyclospora illnesses were higher. Increasing culture-independent diagnostic test (CIDT) usage likely contributed to increased detection by identifying infections that would have remained undetected before widespread CIDT usage. Reducing pathogen contamination during poultry slaughter and processing of leafy greens requires collaboration among food growers and processors, retail stores, restaurants, and regulators.

Background Understanding coupled human-environment factors which promote Aedes aegypti abundance is critical to preventing the spread of Zika, chikungunya, yellow fever and dengue viruses. High temperatures and aridity theoretically make arid lands inhospitable for Ae. aegypti mosquitoes, yet their populations are well established in many desert cities. Methods We investigated associations between socioeconomic and built environment factors and Ae. aegypti abundance in Maricopa County, Arizona, home to Phoenix metropolitan area. Maricopa County Environmental Services conducts weekly mosquito surveillance with CO 2 -baited Encephalitis Vector Survey or BG-Sentinel traps at > 850 locations throughout the county. Counts of adult female Ae. aegypti from 2014 to 2017 were joined with US Census data, precipitation and temperature data, and 2015 land cover from high-resolution (1 m) aerial images from the National Agricultural Imagery Program. Results From 139,729 trap-nights, 107,116 Ae. aegypti females were captured. Counts were significantly positively associated with higher socioeconomic status. This association was partially explained by higher densities of non-native landscaping in wealthier neighborhoods; a 1% increase in the density of tree cover around the trap was associated with a ~ 7% higher count of Ae. aegypti (95% CI: 6–9%). Conclusions Many models predict that climate change will drive aridification in some heavily populated regions, including those where Ae. aegypti are widespread. City climate change adaptation plans often include green spaces and vegetation cover to increase resilience to extreme heat, but these may unintentionally create hospitable microclimates for Ae. aegypti . This possible outcome should be addressed to reduce the potential for outbreaks of Aedes -borne diseases in desert cities. Graphical Abstract

Household air pollution resulting from solid fuel combustion is a leading cause of global morbidity and mortality. Strategies to measure area concentrations of and exposures to PM2.5 in rural homes focus primarily on short-term measurements, often of 24 or 48 h. Little is known about how well these short-term measurements, commonly used exposure metrics in health risk assessment of the impacts of household air pollution exposure, predict longer-term averages. In San Lorenzo District, Guatemala, we deployed the relatively low-cost University of California, Berkeley (UCB) Particle and Temperature Sensor (PATS) for 120-333 days in the kitchens of 8 homes using biomass fuels. We evaluated how well short-term measurements predicted the household-level, entire -sample average. A single 24-h measurement had between a 32% and 39% chance of being within +/- 25% of the household-level mean of all measurements. The Root Mean Square Error (RMSE) of a single 24-h measurement was on average 4.5 times higher than that of the mean of measurements taken once per study week. Alternate strategies - including sampling once per study week or once per study month - with this class of lower-cost sensors yield estimates which have a higher probability of being closer to the overall average value and have smaller errors relative to the overall mean. Evaluation of how well short-term measures predict longer-term averages of household air pollution at prospective study sites allows optimization of field resources to better estimate indoor concentrations and personal exposures.

The International Atomic Energy Agency has coordinated an international project addressing enhancements of methods for modelling the biosphere in post-closure safety assessments of solid radioactive waste disposal. This has resulted in the enhanced BIOMASS methodology that is described elsewhere in this special issue. To a large degree, the enhancements to the BIOMASS methodology arose from experience gained in applying the original methodology, both in the context of other international projects and in assessments of existing or proposed disposal facilities for solid radioactive wastes. Here, this experience is used, together with information on the status of solid radioactive waste disposal programmes worldwide, to identify opportunities for applying the enhanced methodology and for learning from those applications. This provides a basis for identifying research and development to support application of the enhanced methodology in a variety of environmental settings. These research and development requirements include aspects related to climate change under a variety of forcing scenarios, landform development in climatic regimes ranging from cold, polar to arid, tropical, modelling of groundwater flow and contaminant transport in surface-water catchments where both fractured rock and porous sediments are present, and studies of the transport of key radioisotopes of elements central to major biogeochemical cycles, such as those of carbon, chlorine, sulphur and iodine. In addition, some remarks are made on aspects of the application of the enhanced methodology that could imply review and updating of regulations and regulatory guidance, e.g. in relation to the definition of representative persons or groups to be considered in assessments and in respect of approaches to the assessment of radiological impacts on non-human biota. Furthermore, consideration is given as to how the scientific and technical experience that has been gained and methods that have been developed in the context of solid radioactive disposal facilities could support management of contaminated sites and legacy facilities that are likely to require long-term management and stewardship.

In 2016, India introduced the Pradhan Mantri Ujjwala Yojana (PMUY) policy, which offers below-the-poverty-line (BPL) households a free liquified petroleum gas (LPG) connection. Simultaneously, the National and State governments implemented numerous health, housing, and other programs also targeting BPL households. Using a difference-in-differences approach with a non-equivalent comparison group, we provide causal evidence of the total effect of BPL policies on the probability of obtaining an LPG connection, overall LPG consumption, opting for home delivery, and clean cooking access. Using a two-part model of LPG use, the total effect of the policies is a 7.9 and 8 percentage point increase (46.4% and 50.0% change) in the probability of an increase in any positive LPG use for BPL households but no change in the magnitude of LPG use among households with any positive LPG use. We calculate that the overall increase in LPG use due to BPL policies was 0.68 kg per household. We find no effect for home delivery or cooking energy access tier. Our work suggests the need to expand the policy to address consumption more effectively. Finally, this analysis advocates investigation into consumption incentives and the size of the refill subsidy beyond simply improved targeting of BPL households.

Background: Hundreds of thousands of biodigesters have been constructed in Nepal. These household-level systems use human and animal waste to produce clean-burning biogas used for cooking, which can reduce household air pollution from woodburning cookstoves and prevent respiratory illnesses. The biodigesters, typically operated by female caregivers, require the handling of animal waste, which may increase domestic fecal contamination, exposure to diarrheal pathogens, and the risk of enteric infections, especially among young children. Objective: We estimated the effect of daily reported biogas cookstove use on incident diarrhea among children <5y old in the Kavrepalanchok District of Nepal. Secondarily, we assessed effect measure modification and statistical interaction of individual- and household-level covariates (child sex, child age, birth order, exclusive breastfeeding, proof of vaccination, roof type, sanitation, drinking water treatment, food insecurity) as well as recent 14-d acute lower respiratory infection (ALRI) and season. Methods: We analyzed 300,133 person-days for 539 children in an observational prospective cohort study to estimate the average effect of biogas stove use on incident diarrhea using cross-validated targeted maximum likelihood estimation (CV-TMLE). Results: Households reported using biogas cookstoves in the past 3 d for 23% of observed person-days. The adjusted relative risk of diarrhea for children exposed to biogas cookstove use was 1.31 (95% confidence interval (CI): 1.00, 1.71) compared to unexposed children. The estimated effect of biogas stove use on diarrhea was stronger among breastfed children (2.09; 95% CI: 1.35, 3.25) than for nonbreastfed children and stronger during the dry season (2.03; 95% CI: 1.17, 3.53) than in the wet season. Among children exposed to biogas cookstove use, those with a recent ALRI had the highest mean risk of diarrhea, estimated at 4.53 events (95% CI: 1.03, 8.04) per 1,000 person-days. Discussion: This analysis provides new evidence that child diarrhea may be an unintended health risk of biogas cookstove use. Additional studies are needed to identify exposure pathways of fecal pathogen contamination associated with biodigesters to improve the safety of these widely distributed public health interventions. https://doi.org/10.1289/EHP9468

Understanding drivers of disease vectors’ population dynamics is a pressing challenge for human health, however, for short-lived organisms like mosquitoes, landscape-scale models must account for the highly local and rapid scale of their life cycle. Aedes aegypti, a vector of multiple emerging diseases, has been increasing in abundance in desert population centers, where water from precipitation could be a limiting factor. To explain this apparent paradox, we examined daily precipitation and Ae. aegypti abundances at >660 trapping locations per year for 3 years in the urbanized Maricopa County (metropolitan Phoenix), Arizona, USA. Through kriging of weather station data, we connected daily precipitation to subsequent trapped abundances of mosquitoes, and determined the timing and amount of precipitation that result in thresholds of interference with mosquito abundance. Large rainfall events resulted in no trapped mosquitoes 6-8 and 13-14 days later, while 10% of all mosquitoes were trapped in long, precipitation-free periods.

Women and children in rural regions of low-income countries are exposed to high levels of household air pollution (HAP) as they traditionally tend to household chores such as cooking with biomass fuels. Early life exposure to air pollution is associated with aeroallergen sensitization and developing allergic diseases at older ages. This prospective cohort study assigned HAP-reducing chimney stoves to 557 households in rural Guatemala at different ages of the study children. The children’s air pollution exposure was measured using personal CO diffusion tubes. Allergic outcomes at 4–5 years old were assessed using skin prick tests and International Study of Asthma and Allergies in Childhood (ISAAC)-based questionnaires. Children assigned to improved stoves before 6 months old had the lowest HAP exposure compared to the other groups. Longer exposure to the unimproved stoves was associated with higher risks of maternal-reported allergic asthma (OR = 2.42, 95% CI: 1.11–5.48) and rhinitis symptoms (OR = 2.01, 95% CI: 1.13–3.58). No significant association was found for sensitization to common allergens such as dust mites and cockroaches based on skin prick tests. Reducing HAP by improving biomass burning conditions might be beneficial in preventing allergic diseases among children in rural low-income populations.

To evaluate progress toward prevention of enteric infections in the United States, the Foodborne Diseases Active Surveillance Network (FoodNet) conducts active population-based surveillance for laboratory-diagnosed infections caused by Campylobacter, Cyclospora, Listeria, Salmonella, Shiga toxin-producing Escherichia coli (STEC), Shigella, Vibrio, and Yersinia at 10 U.S. sites. This report summarizes preliminary 2021 data and describes changes in annual incidence compared with the average annual incidence for 2016-2018, the reference period for the U.S. Department of Health and Human Services' (HHS) Healthy People 2030 goals for some pathogens (1). During 2021, the incidence of infections caused by Salmonella decreased, incidence of infections caused by Cyclospora, Yersinia, and Vibrio increased, and incidence of infections caused by other pathogens did not change. As in 2020, behavioral modifications and public health interventions implemented to control the COVID-19 pandemic might have decreased transmission of enteric infections (2). Other factors (e.g., increased use of telemedicine and continued increase in use of culture-independent diagnostic tests [CIDTs]) might have altered their detection or reporting (2). Much work remains to achieve HHS Healthy People 2030 goals, particularly for Salmonella infections, which are frequently attributed to poultry products and produce, and Campylobacter infections, which are frequently attributed to chicken products (3).

Because of the severe air pollution in northern China, facemasks have gained popularity in this area in recent years. Although the results of previous studies have shown the effectiveness of wearing facemasks for intercepting particles, the individual differences and the overall health benefits of wearing facemasks have not been comprehensively documented. In this study, using both model and personal tests under various conditions, we test eight major brands of facemasks for their removal efficiencies (REs) of particulate matter (PM) in six size ranges (from 0.3 mu m to > 10 mu m). The results are used to assess the overall exposure reduction at the individual and population levels in Beijing. We find significant differences in REs among PM sizes, facemask brands, pollution levels, and genders. Combining the information on the usage of various brands, facemask wearing rates, and PM2.5 concentrations in the ambient and indoor air in this area, we evaluate the overall effect of facemask wearing on PM2.5 exposure reduction. It is quantitatively demonstrated that because people spend most time indoors, facemask protection is limited. For facemask wearers, the overall exposure can be reduced by less than 20%, whereas the reduction rate is as low as 2.4 +/- 1.6% for the entire adult populations even in the year with the highest level of pollution with an annual mean PM2.5 concentration of 102 +/- 98 mu g.m(-3). As a strategy of self-protection from long-term exposure to particulate matter, wearing facemasks outdoors is inferior to the installation of indoor air purifiers.

The Patsari Cookstove, an improved cook stove is an adaption and improvement of the Lorena Cookstove which has been in use in Guatemala and Mexico since the early 1990's. It is designed and distributed by the Interdisciplinary Group of Rural and Appropriate Technology (GIRA ) located in Patzcuaro, Michoacan, Mexico. In comparison to the Lorena, several improvements have been incorporated into the design of the Patsari including:

Established populations of Aedes aegypti, a mosquito vector of multiple major arthropod-borne viruses, were first found in three California (CA) cities in 2013. From 2013 to April 2021, Ae. aegypti thwarted almost all control efforts to stop its spread and expanded its range to 308 cities, including Exeter, in 22 counties in CA. Population genomic analyses have suggested that multiple genetically distinct Ae. aegypti populations were introduced into CA. However Ae. aegypti collected for the first time in 2014 in Exeter, appeared to be different from three major genetic clusters found elsewhere in CA. Due to intense control efforts by the Delta Vector Control District (DVCD), Ae. aegypti was thought to have been eliminated from Exeter in 2015. Unfortunately, it was recollected in 2018. It was not clear if the reemergence of Ae. aegypti in Exeter was derived from the bottlenecked remnants of the original 2014 Exeter population or from an independent invasion from a different population derived from surrounding areas. The goal of this work was to determine which of these scenarios occurred (recovery after bottleneck or reintroduction after elimination) and if elimination and reintroduction occurred to identify the origin of the invading population using a population genomic approach. Our results support the reintroduction after elimination hypothesis. The source of reintroduction, however, was unexpectedly from the southern CA cluster rather than from other two geographically closer central CA genetic clusters. We also conducted a knockdown resistance mutation profile, which showed Exeter 2014 had the lowest level of resistant alleles compared to the other populations, could have contributed towards DVCD’s ability to locally eliminate Ae. aegypti in 2014.

Foodborne illnesses are a substantial and largely preventable public health problem; before 2020 the incidence of most infections transmitted commonly through food had not declined for many years. To evaluate progress toward prevention of foodborne illnesses in the United States, the Foodborne Diseases Active Surveillance Network (FoodNet) of CDC's Emerging Infections Program monitors the incidence of laboratory-diagnosed infections caused by eight pathogens transmitted commonly through food reported by 10 U.S. sites.* FoodNet is a collaboration among CDC, 10 state health departments, the U.S. Department of Agriculture's Food Safety and Inspection Service (USDA-FSIS), and the Food and Drug Administration. This report summarizes preliminary 2020 data and describes changes in incidence with those during 2017-2019. During 2020, observed incidences of infections caused by enteric pathogens decreased 26% compared with 2017-2019; infections associated with international travel decreased markedly. The extent to which these reductions reflect actual decreases in illness or decreases in case detection is unknown. On March 13, 2020, the United States declared a national emergency in response to the COVID-19 pandemic. After the declaration, state and local officials implemented stay-at-home orders, restaurant closures, school and child care center closures, and other public health interventions to slow the spread of SARS-CoV-2, the virus that causes COVID-19 (1). Federal travel restrictions were declared (1). These widespread interventions as well as other changes to daily life and hygiene behaviors, including increased handwashing, have likely changed exposures to foodborne pathogens. Other factors, such as changes in health care delivery, health care-seeking behaviors, and laboratory testing practices, might have decreased the detection of enteric infections. As the pandemic continues, surveillance of illness combined with data from other sources might help to elucidate the factors that led to the large changes in 2020; this understanding could lead to improved strategies to prevent illness. To reduce the incidence of these infections concerted efforts are needed, from farm to processing plant to restaurants and homes. Consumers can reduce their risk of foodborne illness by following safe food-handling and preparation recommendations.

The COVID-19 quarantine in China is thought to have reduced ambient air pollution. The overall exposure of the population also depends, however, on indoor air quality and human mobility and activities. Here, by integrating real-time mobility data and a questionnaire survey on time-activity patterns during the pandemic, we show that despite a decrease in ambient PM2.5 during the quarantine, the total population-weighted exposure to PM2.5 considering both indoor and outdoor environments increased by 5.7 μg m−3 (95% confidence interval, 1.2–11.0 μg m−3). The increase in population-weighted exposure was mainly driven by a nationwide urban-to-rural population migration before the Spring Festival coupled with the freezing of the migration backward due to the quarantine, which increased household energy consumption and the fraction of people exposed to rural household air pollution indoors. Our analysis reveals an increased inequality of air pollution exposure during the quarantine and highlights the importance of household air pollution for population health in China. Integrating human mobility and activity data with ground-level measurements and air quality models, Shen et al. find that despite a reduction in outdoor PM2.5 during the COVID-19 quarantine in China, overall population exposure to PM2.5 increased.

A large concern with estimates of climate and health co-benefits of "clean" cookstoves from controlled emissions testing is whether results represent what actually happens in real homes during normal use. A growing body of evidence indicates that in-field emissions during daily cooking activities differ substantially from values obtained in laboratories, with correspondingly different estimates of co-benefits. We report PM2.5 emission factors from uncontrolled cooking (n = 7) and minimally controlled cooking tests (n = 51) using traditional chulha and angithi stoves in village kitchens in Haryana, India. Minimally controlled cooking tests (n = 13) in a village kitchen with mixed dung and brushwood fuels were representative of uncontrolled field tests for fine particulate matter (PM2.5), organic and elemental carbon (p > 0.5), but were substantially higher than previously published water boiling tests using dung or wood. When the fraction of nonrenewable biomass harvesting, elemental, and organic particulate emissions and modeled estimates of secondary organic aerosol (SOA) are included in 100 year global warming commitments (GWC100), the chulha had a net cooling impact using mixed fuels typical of the region. Correlation between PM2.5 emission factors and GWC (R2 = 0.99) implies these stoves are climate neutral for primary PM2.5 emissions of 8.8 ± 0.7 and 9.8 ± 0.9 g PM2.5/kg dry fuel for GWC20 and GWC100, respectively, which is close to the mean for biomass stoves in global emission inventories.

The public health community has tried for decades to show, through evidence-based research, that safe water, sanitation, and hygiene (WASH) and clean cooking fuels that reduce household air pollution are essential to safeguard health and save lives in low-income and middle-income countries. In the past 40 decades, there have been many innovations in the development of low-cost and efficacious technologies for WASH and household air pollution, but many of these technologies have been associated with disappointing health outcomes, often because low-income households have either not adopted, or inconsistently adopted, these technologies. In this Viewpoint, we argue that public health researchers (ourselves included) have had an oversimplified understanding of poverty; our work has not focused on insights into the lived experience of poverty, with its uncertainties, stresses from constant scarcity, and attendant fears. Such insights are central to understanding why technologies for safe water or clean cooking are unused by so many households that could benefit from them. We argue that, rather than improved versions of household-scale delivery models, transformative investments in safe water and clean cooking for all require utility-scale service models. Until then, research should focus on interim safe water and clean cooking options that are directed towards the utility-scale service model.