International Journal of Hygiene and Environmental Health

BackgroundBackyard poultry-raising is common in rural Bangladeshi households. Raising poultry contributes to fecal contamination of the domestic environment, increasing childrens exposure to enteric pathogens, including Campylobacter, which has been associated with child stunting. ObjectiveTo investigate the effectiveness of a behavior change communication and counseling intervention to encourage households to confine poultry outside of the household dwelling in a shed at night and improve poultry feces management. MethodsWe conducted a two-arm pre-post pilot study. Households in both arms received the behavior change communication and counseling intervention. Households in the subsidy arm also received ~23 USD for the construction of a poultry shed for nighttime housing. We administered a household survey and spot-check before and after intervention implementation among 37 subsidy and 42 non-subsidy households. ResultsAt endline, 58% of all households had a poultry shed (87% of subsidy and 33% of non-subsidy households) and the percentage of households confining all poultry outside the house the previous night was significantly higher at endline (33%) compared to baseline (2.5%) (prevalence difference [PD]: 30 percentage points [pp]; 95% CI: [19, 41]). Additionally, more households had no visible poultry feces piles inside the house compared to baseline (PD: 26pp 95% CI: [12, 41]), but there were no significant differences in the number of poultry feces piles in the courtyard or veranda. DiscussionOur intervention effectively encouraged households to confine poultry outside of household dwellings at night and to maintain an indoor living space free of poultry feces. Households were willing and able to construct a shed even without a subsidy. Households that received a subsidy were more likely to construct a shed. Future studies should assess if housing all poultry outside the household dwelling reduces childrens exposure to poultry feces enough to mitigate health risks associated with poultry ownership.

BackgroundEnvironmental health services in healthcare facilities --including water, sanitation, hygiene, waste management, cleaning, and infection control--prevent disease and strengthen healthcare delivery. Yet environmental health service provision is inadequate in many low- and middle-income countries (LMICs). Despite the importance of monitoring and improving services, no comprehensive evidence map exists to describe global knowledge and gaps for action and improvement. The study objectives were to comprehensively catalog published literature on environmental health services in healthcare facilities in LMICs by service domain, study type, and relevance to policy and practice. MethodsWe conducted a systematic literature search in 2023 and performed an update in 2025. Through a title/abstract screening and tagging process, we developed a literature inventory that categorized studies by topic, design, and relevance to policy and practice objectives. ResultsThe literature inventory included 4,381 studies. Fifty-eight percent of the studies were baseline assessments of environmental health services, 36% involved formative research (e.g., qualitative methods), and 13% evaluated interventions or implementation strategies. Most studies (62%) examined hygiene at points of care, while 9% examined water and 6% sanitation. Twenty-seven percent of studies examined services in the context of the COVID-19 pandemic. ConclusionsThere is little evidence for effective interventions and implementation strategies to improve and sustain environmental health services, especially for water and sanitation services. Formative research on under-studied services can help policymakers and practitioners identify areas to prioritize investment and programming. Findings can inform the development of research agendas and practical guidelines for improving access to safe healthcare environments.

The prevalence of enteric pathogen detection in children in low-income countries climbs rapidly between birth and 6 months of age. Few studies have tested whether improved household environmental and behavioral hygiene conditions protects infants from exposure to enteric pathogens spread via unhygienic human and animal sanitation conditions, especially during this early window of infancy. This cross-sectional study utilized enrollment survey data among households with 6 month old infants in Kisumu, Kenya participating in the Safe Start cluster-randomized controlled trial to estimate associations between household water access and treatment, animal vectors, sanitation access, hand washing practices, supplemental feeding, and flooring, with the outcomes of caregiver-reported 7-day diarrhea prevalence and sum count of different enteric viruses, bacteria, and parasites pathogens in infant stool. Then, we tested whether household environmental hygiene and behavioral practices moderated associations between infant exposure outcomes and latrine access and domestic animal co-habitation. We found that reported handwashing after handling animals and before eating were strongly associated with lower risk of caregiver-reported diarrhea, while owning and co-habitating with animals (versus no animals), living in a household with vinyl covered dirt floors (versus finished floors), and feeding infants cow milk (versus no milk) were strongly associated with pathogen detection in infants. Caregiver handwashing after child or self-defecation moderated the relationship between shared sanitation (vs private) sanitation access and infant exposure to pathogens such that handwashing had the greatest benefit for preventing pathogen exposure of infants in households with private latrines. In the absence of handwashing, access to private sanitation posed no benefits over shared latrines for protecting infants from exposure. Our evidence highlights eliminating animal co-habitation, improving flooring, improving post-defecation and food-related handwashing, and improving safety of cow milk sources and/or safe household storage of milk as interventions to prevent enteric pathogen exposure of infants less than 6 months age. Key QuestionsO_ST_ABSWhat is already known?C_ST_ABSThe population prevalence of enteric infections and diarrhea climbs rapidly in the first year of life. Risk factors for pediatric infections include unhygienic human and animal sanitary conditions that introduce feces into the environment, as well as intermediate environmental and behavioral exposure pathways. Research examining the mitigating role of improved environmental and behavioral conditions in preventing infant exposure to human and animal sanitary conditions is limited. What are the new findings?Contact with domestic animals and feeding infants cow milk are leading risk factors for exposure to enteric pathogens by 6 months age in Kisumu, while handwashing after animal handling and before eating are protective factors against self-reported diarrhea. The benefits of access to a private improved latrine (versus shared) for protecting infants from pathogen exposure were conditional upon caregivers washing hands after defecation or child-defecation. What do the new findings imply?Interventions that keep animals out of infant living spaces and that improve food-related and post-defecation handwashing may be the most effective strategies for controlling the population prevalence of enteric infections in infants between birth and 6 months age in Kisumu and similar settings.

BackgroundDiarrheal disease is a leading cause of childhood morbidity and mortality globally. Household water, sanitation, and handwashing (WASH) interventions can reduce exposure to diarrhea-causing pathogens, but climatic factors may impact their effectiveness. Information about effect heterogeneity under different weather conditions is critical to intervention targeting. MethodsWe analyzed data from a trial in rural Bangladesh that compared child diarrhea prevalence between clusters that were randomized to different WASH interventions between 2012-2016 (NCT01590095). We matched temperature and precipitation measurements to households by geographic coordinates and date. We estimated prevalence ratios (PR) using generative additive models and targeted maximum likelihood estimation to assess the effectiveness of each WASH intervention under different environmental conditions. FindingsGenerally, WASH interventions most effectively prevented diarrhea during monsoon season, particularly following weeks with heavy rain or high temperatures. Compared to the control arm, WASH interventions reduced diarrhea by 51% (95% CI 33%-64%) following periods with heavy rainfall vs. 13% (95% CI -26%-40%) following periods without heavy rainfall. Similarly, WASH interventions reduced diarrhea by 40% (95% CI 16%-57%) following above-median temperatures vs. 17% (95% CI -38%-50%) following below-median temperatures. The influence of precipitation and temperature varied by intervention type; for precipitation, the largest differences in effectiveness were for the sanitation and combined WASH interventions. InterpretationWASH intervention effectiveness was strongly influenced by precipitation and temperature, and nearly all protective effects were observed during the rainy season. Future implementation of these interventions should consider local environmental conditions to maximize effectiveness. FundingBill & Melinda Gates Foundation; National Institute of Allergy and Infectious Diseases; National Heart, Lung, And Blood Institute; National Institute of General Medical Sciences; Stanford University School of Medicine; Chan Zuckerberg Biohub Research in Context PanelO_ST_ABSEvidence before this studyC_ST_ABSWe searched Google Scholar using the search terms "sanitation" OR "hygiene" OR "WASH" OR "water quality"; AND "heterogen*" OR "effect modif*"; AND "temperature" OR "precipitation" OR "rain*" OR "climate" OR "environmental"; AND "diarrhea" OR "enteric infection"; AND "risk" AND/OR "factors". In general, the effect modification of WASH interventions on diarrhea by weather is not well studied. One study in Ecuador investigated different relationships between rainfall, diarrhea, and unimproved sanitation and water sources. They found that unimproved sanitation was most strongly associated with elevated diarrhea after low rainfall, whereas unimproved water sources were most strongly associated with elevated diarrhea after heavy rainfall. In a similar setting in Ecuador, a separate study found that drinking water treatments reduced increases in diarrhea after heavy rainfall that followed dry periods, while sanitation and hygiene had no impact on the relationship between heavy rainfall and diarrhea. One study in Rwanda also found that high levels of runoff were protective against diarrhea only in households with unimproved toilets. In Bangladesh, one study found that access to tubewells was most effective at reducing childhood diarrhea in non-flood controlled areas. High heat can accelerate the inactivation of enteric pathogens by water chlorination, but no studies have examined how temperature influences the effectiveness of sanitation or hygiene interventions. No prior studies have estimated differences in WASH effectiveness under varying weather conditions within a randomized trial. Added value of this studyTo our knowledge, this is the first study to assess differences in household-level WASH intervention effectiveness by weather conditions in a randomized trial. We spatiotemporally matched individual-level data from a trial in rural Bangladesh to remote sensing data on temperature and precipitation and estimated differences in the effectiveness of WASH interventions to prevent childhood diarrhea under varying levels of these environmental factors. Implications of all the available evidenceWe found that WASH interventions were substantially more effective following periods with higher precipitation or higher temperatures. We observed the largest effect modification by precipitation for a sanitation intervention. This may be because compared to water and handwashing interventions, the sanitation intervention blocked more pathways through which enteric pathogens reach water, soil, and flies following heavy rainfall. In regions like Bangladesh, extreme weather is expected to become more common under climate change but WASH interventions might mitigate increases in childhood diarrhea due to climate change.

Background: Household insecticides are widely used for domestic pest control, yet exposure patterns in traditionally underserved populations remain poorly characterized. In the Brazilian Amazon, data on use patterns among older adults living in riverine communities are particularly scarce. Objective: To describe the prevalence, frequency, duration, application practices, and types of household insecticides used by older adults living in near-urban riverine insular communities in the Brazilian Amazon. Methods: Cross-sectional, population-based door-to-door survey conducted from August 2022 to July 2025 in four islands (Cotijuba, Mosqueiro, Outeiro, and Combu) in the city of Belem, Brazil. All residents aged 60 years or more registered in the primary care system were invited to participate. Trained interviewers administered an in-person standardized questionnaire to participants on current household insecticide use, frequency, duration, self-application, protective equipment, insecticide types, and product brands. Results: Among 1,101 screened individuals, 1,084 were included (median age at evaluation: 68 years). Overall, 78.4% reported current use of household insecticides. Weekly or more frequent use was reported by 58.9%, and 33.4% reported use for more than 5 years. Self-application was common (57.5%), whereas use of protective equipment was rare (8.2%). Aerosol sprays were the most frequently reported type (39.4%). Commonly recalled aerosols contained pyrethroid mixtures including cypermethrin, imiprothrin, prallethrin, and transfluthrin. A substantial proportion of participants reported using unregulated products and veterinary-only insecticides for household purposes. Conclusions: Household insecticide use is highly prevalent and frequent in Amazonian riverine communities, with minimal use of protective equipment and substantial irregular practices, underscoring the need for targeted risk communication and surveillance.

IntroductionCommunity Led Total Sanitation (CLTS) has been used to increase sanitation coverage and use. However, robust evaluations of CLTS with and without other community-based interventions remain limited. We evaluated the effectiveness of standard CLTS and CLTS combined with a community-based "Care Group" model on sanitation and hygiene outcome compared to a non-intervention control in Chiradzulu District, rural Malawi. MethodsWe conducted a three-arm controlled before-and-after trial. One arm received standard CLTS, one received CLTS plus Care Group (CLTS+CG), and one served as control. Baseline and endline surveys were administered to 1,400 randomly sampled households. Difference-in-difference analysis assessed changes in sanitation and handwashing outcomes between May-June 2023 (baseline) and April-May 2024 (endline). ResultsAccess and use of sanitation facilities were generally high at baseline in all study arms. The primary outcome of the trial was access to a private sanitation facility of any quality. Both intervention arms were associated with improved odds of household having access to a private sanitation facility at endline compared to the control (CLTS: adjusted odds ratio [aOR] 3.11 (95% confidence interval [CI] 2.06-4.70); CLTS+CG: aOR 2.16 (CI 1.34-3.48)). However, there was no evidence that either intervention increased the odds of having a sanitation facility meeting quality standards for Sustainable Development Goals (SDG) 6. There was no observable difference between the two treatment arms on reported sanitation use. The odds of having a basic handwashing facility were higher in the CLTS+CG group versus control (aOR 2.62, CI 1.19-5.75) and CLTS+CG group versus standard CLTS group (aOR 2.89, CI 1.14-7.34); however, absolute increases in handwashing station coverage were limited. ConclusionThis study suggests that CLTS is unlikely to result in improvements in sanitation of quality required to meet SDG targets and has minimal impact on household level investment in hygiene facilities. Standard CLTS should no longer be the de facto rural sanitation policy.

Leptospirosis is a globally important environmentally transmitted disease, with approximately one million cases and 60,000 deaths reported annually. In low-income urban communities, inadequate sanitation, drainage and waste management may increase human exposure to contaminated environments. This study investigated the influence of environmental engineering risk factors on Leptospira exposure in four disadvantaged urban communities (favelas) in Salvador, Brazil. A high-precision georeferenced field survey was developed to identify, map and characterise sanitation, stormwater drainage and solid waste infrastructure. Cross-sectional spatial analyses of baseline data were used to assess associations between environmental risk factors and the residential locations of individuals with anti-Leptospira antibodies. Seropositive individuals tended to reside closer to environmental risk factors and at lower relative elevations. Density analyses indicated that seropositive individuals tended to reside closer to inadequate or partially adequate sewerage components than to sewage-contaminated streams or open sewage points. Inadequate streets showed also showed high density peaks, suggesting that exposure may occur through frequent contact with contaminated runoff and standing water. In contrast, open waste dumping sites and vacant lots showed weaker and more diffuse spatial patterns. The findings highlight the importance of infrastructure quality shaping leptospirosis risk within urban informal settlements. The proposed methodology provides a practical approach for high-resolution characterisation of environmental exposure pathways and may support targeted engineering interventions and epidemiological investigations of leptospirosis and other environmentally transmitted diseases.

Summary Background: Wastewater and environmental surveillance (WES) enables community-level monitoring of infectious diseases. Most progress has focused on sewer-based surveillance, yet nearly half of the global population relies on non-sewered sanitation. In non-sewered settings, urban drainage channels have been used for poliovirus environmental surveillance, but their potential for a multi-pathogen WES with spatially defined catchments, and comparability to sewer-based surveillance, remains under-explored. Methods: Ten drainage channel sampling points with delineated micro-catchments (0.95-3.83 km2 with 12,885-44,146 people) were selected within Kampala. A total of 255 drainage channel and 54 wastewater treatment plant (WWTP) influent samples were collected during two campaigns in March and September-October 2025. A multi-target panel was quantified by digital PCR, including enteric viruses (Norovirus GI and GII, Rotavirus), respiratory viruses (SARS-CoV-2, Influenza A and B viruses, Respiratory Syncytial Virus (RSV)), non-O1/O139 Vibrio cholerae (V. cholerae), and Pepper Mild Mottle Virus (PMMoV) as a fecal indicator. Findings: Enteric viruses, non-O1/O139 V. cholerae, and PMMoV were consistently detected across all drainage channels and WWTP influents. Concentrations were generally lower in drainage than WWTP influents, except for non-O1/O139 V. cholerae. When normalized by PMMoV, concentrations across most drainage channels were comparable to WWTP influents, although comparability varied by target and location. Both concentrations and PMMoV-normalized concentrations varied across sampling locations. Trends between campaigns varied by pathogen target and were not explained by any single micro-catchment characteristic. Influenza A virus was the most frequently detected respiratory virus (8-23% in drainage channels; 3-10% in WWTP influents), while SARS-CoV-2, Influenza B, and RSV were rarely detected. Interpretation: PMMoV-normalized concentrations across most micro-catchments were comparable to WWTP influents, with spatial heterogeneity implying neighborhood-level differences in disease prevalence. Catchment-delineated drainage surveillance has potential to offer spatially resolved public health information in non-sewered settings comparable to sewer-based wastewater monitoring. Funding: Eawag Discretionary Funding

BackgroundEnvironmental and Regulatory (ER) services, provided by local authorities, play a key role in public health protection. Food safety teams within ER services carry out regular food hygiene inspections, advice and education visits, and investigate foodborne disease outbreaks. Following the 2008 financial crisis, local authorities have faced substantial funding cuts. This study investigates the impact of local government expenditure reductions on food safety services. MethodsWe used fixed effects panel regression to analyse the effect of food safety expenditure reductions on food hygiene staffing levels, food hygiene interventions (e.g. inspection, sampling, advice and education), and the proportion of establishments rated food hygiene compliant. We also examined the effect of staff reductions on the number of interventions achieved and establishment compliance. ResultsA {pound}1 decrease in food safety expenditure per capita was associated with a 2% (95% CI 0.7% to 3.3%) decrease in staffing levels and a 1.7% (95% CI 0.2% to 3.3%) decrease in the number of interventions achieved per establishment. One-unit reduction in staff was associated with a 49.2% (95% CI 18.7%, 87.6%) decrease in the number interventions achieved. We found no evidence of an association between expenditure or staff levels and the proportion of compliant establishments. ConclusionSpending reductions negatively impact the capacity of food safety teams to provide key services. Reductions in food safety expenditure significantly impact food hygiene staff levels and service provision. This raises concerns about the capacity of food safety teams to operate and the potential for increased public risk of gastrointestinal infections.

Household environments in low-resource settings can become contaminated with fecal matter from multiple sources, including humans and domestic animals. Identifying the source of fecal contamination is critical for designing targeted interventions to reduce exposure to enteric pathogens, particularly for young children who bear the majority of the enteric disease burden. Using data from 140 households with children enrolled in the ECoMiD cohort study in northwestern coastal Ecuador, we (1) characterized source-specific fecal contamination in samples from household floors and maternal and child hands, and (2) identified animal-related and Water, Sanitation and Hygiene (WASH) conditions associated with the presence and concentrations of these markers. We used five qPCR-based microbial source tracking (MST) markers to detect fecal contamination from avian (GFD), canine (DG37), swine (Pig2Bac), ruminant (Rum2Bac), and human (HF183) sources. Prevalence ratios (PR) and mean differences comparing the presence/absence and concentration, respectively, of MST markers between households with and without each animal-related or WASH condition were estimated using generalized linear models with Poisson and Gaussian distributions. Animal MST markers tracked strongly with several animal-related conditions, whereas associations between the human MST marker and household demographic and WASH conditions were more limited. Animal ownership (PR 1.53; 95% CI: 1.04-2.26) was associated with higher prevalence of animal MST markers on floors. Households reporting animal feces indoors had higher prevalence of animal MST markers on floors (PR 1.84; 95% CI: 1.17-2.89), and higher concentrations of animal MST markers on child hands (mean difference 0.27 gene copies (gc)/m2; 95% CI: 0.12-0.41) and maternal hands (mean difference 0.10 gc/m2; CI: 0.02-0.18). Animal feces left unremoved outside the home were associated with higher prevalence of animal MST markers on maternal hands (PR 2.31; 95% CI: 1.11-4.81). Mothers reporting direct contact with animals had higher concentrations of animal MST markers on their children hands (mean difference 0.12 gc/m2; 95% CI: 0.02-0.21). Higher FECEZ scores, an overall metric for animal exposure, were associated with higher prevalence of animal MST markers on maternal hands (PR 2.94; 95% CI: 1.17-7.40). For human fecal contamination, the presence of E. coli on child hands was associated with higher prevalence of human MST markers on floors (PR 1.30; 95% CI: 1.00-1.68). Our findings reinforce household floors and maternal and child hands as key reservoirs of fecal contamination and point to future potential targets worth exploring for interventions in similar high-burden settings.

Intermittent water supplies (IWS) serve >1 billion people globally and can transmit waterborne infections. How often and for how long supply is delivered varies between and within IWS systems. The UN Sustainable Development Goals target having water available when needed for >=12 hours/day or >=4 days/week but there are scarce data on how supply frequency/duration within IWS affect health outcomes. We conducted a matched study in Hubli-Dharwad, India, a city served partially by continuous water supply (CWS) since 2007 and partially by IWS. We enrolled 2220 CWS and 2218 IWS households matched on socioeconomics and sanitation. We compared diarrhea prevalence in children <5 years and typhoid fever incidence between households with different water supply characteristics using generalized linear models with robust standard errors and adjusting for socio-demographics and sanitation. Among IWS households, the median supply frequency was every 8 days (interquartile range [IQR]=7-8), and the median supply duration was 4 hours (IQR=3-5). IWS households had 36% higher prevalence of child diarrhea (prevalence ratio [PR]=1.36, 1.00-1.84) and 78% more typhoid fever cases (cumulative incidence ratio [CIR]=1.78, 1.05-3.02) than CWS households. IWS households meeting the UN criterion and those in the top quintiles of supply frequency and duration (receiving water once every 1-6 days or for 7-24 hours per supply cycle) had similar health outcomes as CWS households. IWS households below the UN criterion had higher diarrhea prevalence (PR=1.41, 1.03-1.93) and more typhoid fever cases (CIR=1.93, 1.15-3.22) than CWS households, as well as more typhoid fever cases than IWS households meeting the criterion (CIR=3.66, 1.37-9.79). IWS households in the bottom quintiles of supply frequency and duration (receiving water once every 9-15 days or for <=3 hours per supply cycle) had 45-72% higher child diarrhea prevalence and twice as many typhoid fever cases than CWS households (p-values<0.05). These findings support global efforts to implement CWS. Our results also highlight that increasing supply frequency and duration in IWS systems in the interim can deliver health benefits, and the UN criterion of having water available when needed improves health.

IntroductionWhile hygiene promotion is frequently included in sanitation programmes, few studies directly evaluate the effect of these interventions on hygiene outcomes. We assessed the effectiveness of a district-level Community-led Total Sanitation (CLTS) intervention with and without locally managed Care Groups (CG) on observed sanitation and hygiene behaviours in a rural area of Chiradzulu District, Malawi. MethodsThis was a controlled before-and-after trial with two intervention arms and a control group implemented in three sub-districts (also known as Traditional Authorities [TAs]) in Chiradzulu District, Malawi. Two TAs received CLTS, which included an additional low-intensity government-led hygiene promotion campaign. One TA received the standard CLTS intervention (CLTS group), and one received the same intervention but with additional sanitation and hygiene promotion delivered through local Care Groups (CLTS+CG group). The third TA served as the control group. Hygiene and child faeces disposal outcomes were measured by fieldworker direct observation in a purposively sampled subset of 96 to 140 households per arm enrolled in the main trial at baseline (June 2023) and at endline (May 2024). We estimated intervention effects on observed handwashing behaviour and safe child faeces disposal with hierarchical logistic regression models. ResultsIn our per protocol analysis, neither intervention was associated with differences in observed handwashing with soap compared to the control arm nor with differences in observed child faeces disposal. Additional analyses found that both interventions were associated with large increases in hand rinsing with water only compared to control groups (CLTS+CG group adjusted relative risk ratio [aRRR] = 2.80, CI = 1.81, 4.33; CLTS group aRRR = 1.76, CI = 1.10, 2.83). The CLTS+CG intervention was associated with a slight increase in hand rinsing compared to the CLTS only group (aRRR = 1.65, CI = 1.01, 2.69). ConclusionThe CLTS+CG and CLTS interventions were associated with an increase in hand rinsing at critical junctures but not handwashing with soap, suggesting that current hygiene programmes require further focus on soap access and use. Future research should investigate barriers to the availability and competing uses of soap in households. Both interventions did not increase safe child faeces disposal, though the sample size was small. Future research should investigate further integration of child faeces management into CLTS and CG behaviour change interventions.

Nontyphoidal Salmonella infection, or salmonellosis, typically presents with diarrhea, fever, and abdominal cramps and affects over 1 million people in the U.S. annually. Infants and young children are most susceptible to Salmonella infection, which can require hospitalization and lead to death. The vast majority of salmonellosis is foodborne and its incidence is highest during hot weather. This study used U.S. age-specific Salmonella surveillance data and geographic-specific temperature data to assess the relationship between summer season and Salmonella infection according to age group and geographic region. The Salmonella infection rate per 100,000 population was highest in infants (111.95), followed by children aged 1-4 (40.66), those aged 5-17 years (12.06), and adults 18 and older (10.84). Compared to winter months (December to February), an excess of approximately 8 infections per 100,000 infants for summer months (June to August) was observed. The corresponding excess was 15 per 100,000 infants for in the South. These findings suggest greater vulnerability among infants to future temperature increases.

Boiling raw milk before drinking is a common practice in Bangladesh, but its impact on residue levels of ciprofloxacin and enrofloxacin is not well known. This study looked at these antibiotics in 120 raw cow milk samples from 12 dairy areas near Dhaka, collected between November 2023 and March 2024. Each sample was split into two parts: one tested as raw milk and the other after boiling at home for 15 minutes. Residues were checked using matrix-matched HPLC-UV. Ciprofloxacin and enrofloxacin were found in 113 out of 120 samples (94.2%), and at least one of them was present in 117 samples (97.5%). We considered a level of 12.5 micrograms per liter or higher as detected. The average combined amount of these antibiotics dropped from 194.61 micrograms per kilogram in raw milk to 179.57 micrograms per kilogram after boiling, a decrease that was statistically significant (p < 0.001). However, the percentage of samples exceeding the EU maximum residue limit of 100 micrograms per kilogram only went down from 92.5% in raw milk to 90.0% after boiling, which was not statistically significant (p = 0.250). Using national milk consumption data as an estimate of intake, the hazard index for adults was 0.360 for raw milk and 0.332 for boiled. Calculated with a 10 kg body weight, these values were 2.159 and 1.992, respectively. Overall, boiling at home did reduce the levels of ciprofloxacin and enrofloxacin, but it usually did not bring high-residue samples below the EU limit.

BackgroundTyphoid fever is a major public health issue in low- and middle-income countries. It is transmitted through fecally contaminated food or water and thus improving water, sanitation, and hygiene (WASH) is considered key to its control. We sought to quantify the association between WASH and typhoid fever. MethodsWe updated a previous review by including new findings from the literature indexed in Web of Science, Embase, and PubMed. We kept the search terms, typhoid and case-control, consistent with the previous review. We assessed the risk of bias using the Risk of Bias in Non-Randomized Studies of Interventions (ROBINS-I). We categorized WASH exposures according to the WHO/UNICEF Joint Monitoring Programme for Water Supply, Sanitation and Hygiene (JMP) classification. We conducted a Bayesian random-effects meta-analysis of odds ratios (ORs) extracted from the studies without a critical risk of bias. FindingsWe identified 25 eligible articles including 19 articles from the previous review. Pooled ORs indicated limited hygiene (OR = 2.26, 95% CrI: 1.38 to 3.64), untreated water (OR = 2.21, 95% CrI: 1.53 to 3.48) and using surface water (OR = 2.16, 95% CrI: 1.24 to 3.60) increased odds of culture-confirmed typhoid fever. On the other hand, basic hygiene (OR = 0.6, 95% CrI: 0.38 to 0.97) and treated water (OR = 0.62, 95% CrI: 0.41 to 0.89) reduced odds of culture-confirmed typhoid fever. ConclusionOur analyses updated quantitative evidence of association between WASH and typhoid fever. Our study findings will be useful to infer actionable insights on the most effective ways to control typhoid fever in low- and middle-income countries. Our analyses also offer a possibility to leverage JMP WASH data to explore potential burden of typhoid fever. Systematic review registrationPROSPERO 2021 CRD42021271881 Author SummaryTyphoid fever is a major public health issue in the low- and middle-income countries. It is transmitted through fecally contaminated food or water and thus improving water, sanitation, and hygiene (WASH) is considered key to its control. We quantified the association between WASH and typhoid fever through a systematic review of the case-control studies and meta-analyses of extracted odds ratios (ORs). We categorized WASH exposures according to the WHO/UNICEF Joint Monitoring Programme for Water Supply, Sanitation and Hygiene (JMP). We used a Bayesian random-effects model to account for the heterogeneity of studies that were conducted at different times and places, and adjusted potential bias differently. Pooled ORs indicated that limited hygiene (OR = 2.26, 95% CrI: 1.38 to 3.64), untreated water (OR = 2.21, 95% CrI: 1.53 to 3.48) and using surface water (OR = 2.16, 95% CrI: 1.24 to 3.60) increased odds of typhoid fever. On the other hand, basic hygiene (OR = 0.6, 95% CrI: 0.38 to 0.97) and treated water (OR = 0.62, 95% CrI: 0.41 to 0.89) reduced odds of culture-confirmed typhoid fever. Our analyses updated evidence for the association between WASH and typhoid fever. The updated evidence strongly supports that improved WASH such as improved water source, water treatment, and basic hygiene will help reduce typhoid fever in low- and middle-income countries. By linking WASH exposures to new JMP WASH categories our analyses also offer a possibility to leverage JMP WASH data sets to explore potential burden of typhoid fever.

This protocol is reported in accordance with the SPIRIT 2025 guidelines for clinical trial protocols. IntroductionYoung children, from birth to age 5 y are particularly vulnerable to indoor air pollutants and respiratory pathogens. Portable air purifiers (or filtration) and upper-room ultraviolet germicidal irradiation (UVGI) are two widely used interventions with the potential to improve indoor air quality (IAQ) and reduce sick-related absences. However, a review of the literature revealed no real-world randomised studies evaluating their effectiveness in reducing young childrens sick-related absences in early care and education (ECE) classrooms. Methods and AnalysisThe OK-AIR study is a longitudinal, cluster-randomised 2x2 factorial trial conducted in Head Start centers using two implementation cohorts: Cohort 1 (five Head Start centers and 20 classrooms from 2023 to 2024) and Cohort 2 (11 centers and 59 classrooms from 2025 to 2026), with expanded inclusion of rural areas. Cohort 1 enrolled 204 children, 48 teachers and 5 site directors, and Cohort 2 enrolled 462 children, 97 teachers and 11 site directors. Within each center, four classrooms are randomised to: (1) control; (2) portable filtration; (3) upper-room ultraviolet germicidal irradiation (UVGI); or (4) both interventions. Cohort 2 was initially planned as a second factorial trial but was amended to a purifier-only design due to funding changes; details are provided in the protocol amendments section. We collect continuous IAQ data, including particulate matter (PM) with aerodynamic diameters [&le;]1 {micro}m (PM1), [&le;]2.5 {micro}m (PM2.5), [&le;]4 {micro}m (PM4), and [&le;]10 {micro}m (PM10); total volatile organic compounds (TVOCs) index; nitrogen oxides (NOx) index; carbon monoxide (CO), noise; temperature; and relative humidity, alongside daily child absences. Seasonal environmental surface swabs (dining tables and toilet flooring) are tested by Reverse-Transcriptase quantitative Polymerase Chain Reaction (RT-qPCR) for Influenza A/B, Respiratory Syncytial Virus (RSV), Human Parainfluenza Virus Type 3 (HPIV3), Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), and Norovirus. IAQ monitoring is structured across Winter, Spring, Summer, and Fall, including designated baseline/off-period weeks to characterize temporal and seasonal variability in environmental measures across classrooms and centers. Multi-informant surveys (Director, Teacher, Parent) capture contextual factors, and childrens social-emotional development is assessed using teacher ratings on the Devereux Early Childhood Assessment (DECA). The primary outcome is the sick-related absence rate, analyzed as cumulative absences over the attendance year while accounting for clustering by school and classroom using generalized mixed-effects models. Secondary outcomes include childrens social-emotional ratings, IAQ metrics and pathogen detection rates; analyses of IAQ incorporate time/seasonal structure, and season-stratified absenteeism analyses will be treated as secondary/exploratory refinements. An economic evaluation will estimate incremental intervention costs and cost-effectiveness/cost-benefit (such as cost per sick-related absence day averted). Ethics and DisseminationThis study was approved by the Institutional Review Board (IRB) at the University of Oklahoma. Findings will be shared through peer-reviewed publications; presentations at local, state, and national conferences; research briefs developed for lay and policy audiences; and community briefings prioritizing the participating early childhood programs and communities. DisclaimerThe views expressed are those of the authors and do not reflect the official views of the Uniformed Services University or the United States Department of War. Strengths and Limitations of This StudyO_LIReal-world longitudinal cluster RCT: The study uses a rigorous longitudinal cluster-randomised 2x2 factorial design in real-world ECE settings. C_LIO_LICombined interventions: Interventions target both air filtration and disinfection, allowing for combined and comparative evaluation. C_LIO_LIObjective air-quality monitoring: Continuous monitoring of IAQ metrics provides objective and reliable data on environmental change. C_LIO_LIEnvironmental pathogen surveillance: qPCR on surface swabs yields an objective biological outcome to triangulate with IAQ and absences. C_LIO_LIComprehensive context and child measures: Multi-method and multi-reporter data collection includes Head Start attendance records, continuous air monitoring, pathogen detection, contextual surveys completed by center directors, teachers, and parents, and standardized social-emotional assessments (DECA) completed by classroom teachers. Head Start program records providing childrens longer-term health data available through Health Insurance Portability and Accountability Act (HIPAA) authorization. C_LIO_LIClustered/temporal complexity: Seasonal design accounts for variation over time but may introduce complexity in modeling temporal effects. C_LIO_LIPractical Implications: Study findings will have practical implications for Head Start and other ECE programs striving to maximize child attendance with cost effective strategies. C_LI

In low-income countries, ESBL-producing Escherichia coli (ESBL-EC) is frequently detected in humans, animals and household environments, indicating widespread exposure to antimicrobial resistance (AMR). Established risk factors such as antibiotic use do not explain the high community carriage of AMR in all settings; identifying the dominant exposure pathways can inform interventions against AMR. We aimed to investigate (i) animal-human-environment sharing of AMR by assessing associations between the abundance of ESBL-EC in the household environment, domestic animal feces and young children's stool and (ii) household factors associated with ESBL-EC abundance in these reservoirs. We enrolled 112 households from the CRADLE trial in rural Bangladesh. We enumerated ESBL-EC in drinking water, food, child hand rinses, outdoor soil, indoor floor swabs, chicken and cow feces, and stool from children aged 6 months. We recorded indicators of sanitation, animal ownership/management, human and animal antibiotic use, and child exposure behaviors using structured questionnaires and spot checks. The highest prevalence of ESBL-EC was in child stool (95.6%) and animal feces (82.3-96.9%), followed by soil (48.2%) and floors (36.6%); < 10% of food, child hands and drinking water harbored ESBL-EC. The abundance of ESBL-EC in child stool was not associated with its abundance in any sampled matrix; the abundance in chicken but not cow feces showed positive correlations with soil, floors, child hands, and drinking water (correlation coefficients: 0.19-0.39, p-values < 0.05). Higher-quality latrines (improved, pour-flush, with slab) were associated with lower ESBL-EC abundance across matrices; unsafe animal management (animals roaming or spending the night inside the home) was associated with higher abundance. Child antibiotic use and exposure behaviors (soil ingestion, time spent on floor) were not associated with ESBL-EC abundance in child stool. We observed high AMR colonization among young children and domestic animals in rural Bangladesh not explained by traditional fecal-oral exposure pathways. Future studies should explore additional pathways and assess whether sanitation and animal management improvements can reduce AMR.

BackgroundThe rapid growth of the worlds urban population has contributed to the expansion of informal urban settlements in many cities across the world. In these settings, lack of safe sanitation combined with high population density and poverty contributes to heightened health risks for often vulnerable populations. The aim of this study was to evaluate the effect of a shared, onsite sanitation intervention on the nutritional status of children in Maputo, Mozambique. MethodsThe Maputo Sanitation (MapSan) trial was a controlled before-and-after study to evaluate the effect of a shared, onsite sanitation intervention on child health in Maputo, Mozambique. Here, we report the effects on childhood stunting, wasting and underweight, and height-for-age, weight-for-height and weight-for-age z-scores. Children were enrolled aged 1-48 months at baseline and outcomes were measured before and 12 and 24 months after the intervention, with concurrent measurement among children in a comparable control arm. The primary analysis was intention-to-treat. The trial was registered at ClinicalTrials.gov, number NCT02362932. ResultsWe enrolled 757 and 852 children in the intervention and control groups respectively. There was no evidence for an effect of the intervention on any outcome at 12 or 24 months of follow-up except for wasting where there was very weak evidence for an effect (adjusted prevalence ratio: 0.497; 95% CI: 0.22-1.11; p=0.09). In two exploratory analyses - one including only those children born into compounds post-intervention and a second excluding children in control compounds which had independently improved their sanitation facilities during follow-up - we found that stunting increased in the intervention group whilst wasting decreased. ConclusionsThis study contributes to the growing evidence on the role of sanitation in shaping child health outcomes in informal urban settlements. We found no evidence for an effect on stunting and weak evidence for an effect on wasting. More research is needed to understand how sanitation can reduce childhood undernutrition in complex urban environments.

Communities relying on drinking-water storage routinely document containers as a reservoir for pathogens when they are not properly cleaned. Although lab-based research provides guidance on cleaning protocols, gaps remain in understanding: 1) what methods are practiced, and 2) method effectiveness at reducing biofilm growth. In partnership with AFMAC, this pilot explored biofilm contamination in household water storage containers of four Zambian communities engaged in WASH-promoting community health clubs and health promoters. A mixed-methods design was used: 15-20 households per community completed a knowledge, attitudes, and practices survey and provided whole-container biofilm samples. Four focus group discussions with program members and four interviews with AFMAC staff explored container cleaning sensitizations. Findings revealed household awareness of container cleaning, inconsistent cleaning practices, and high levels of biofilm in 100% of storage containers. The absence of a standardized container cleaning module, reliance on visual cues as a proxy for microbial safety, and disproportionate burden placed on women underscore critical gaps in current programming and highlight container cleaning as a critical pathway to interrupt recontamination. This pilot highlights the need for locally adapted, practical protocols using accessible materials. Advancing container hygiene through integrated, adaptive, and scalable approaches is essential for reducing public health risks from unsafe water storage and improving point-of-use water quality. SynopsisField evidence on household water storage container cleaning is limited. The study found high biofilm levels and inconsistent cleaning of household water storage containers, revealing a gap between knowledge and practice in maintaining safe water quality. Table of Content Graphic O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=142 SRC="FIGDIR/small/25339087v1_ufig1.gif" ALT="Figure 1000"> View larger version (49K): org.highwire.dtl.DTLVardef@1ccb1ddorg.highwire.dtl.DTLVardef@1b15447org.highwire.dtl.DTLVardef@11416b3org.highwire.dtl.DTLVardef@1de5f0b_HPS_FORMAT_FIGEXP M_FIG C_FIG

Transmission of Cryptosporidium can occur via contaminated food or water, contact with animals or other people. Exposures are often identified from outbreak investigations, but sources for sporadic disease and pathways to infection are still unclear. The aim of this review is to consolidate the literature to describe exposures associated with human cryptosporidiosis in industrialised countries. Methods followed the recommendations made in the Cochrane Handbook for Systematic Reviews of Interventions. Three steps were used to identify the literature including electronic database searching using PubMed, Scopus and Web Of Science; reference list trawling; and an exploration of the grey literature. Quality was assessed using the Newcastle-Ottawa Scale. Screening of results was undertaken by two reviewers and data extracted using a standardised form. A narrative summary presented. Papers were included if they reported on sporadic cases and were published between 2008 and 2018. Exposures were grouped into pathways. After full-text screening, eight articles (comprising 11 studies) were included, and seven (comprising 10 studies) were suitable for further synthesis. None of the identified grey literature was included. Four studies described case-control methods, two were case-case studies and one cross-sectional. Study year ranged from 1999 to 2017 and the studies were conducted in five, large countries in three continents: Europe (UK and the Netherlands), North America (USA, Canada), and Australia. Included papers investigated water and animal exposures most frequently. Recreational water was not a major source of sporadic illness in this review. The person-to-person pathway represented the most consistent finding, with all three studies reporting on contact with a symptomatic individual demonstrating correlations between exposure and disease. This applied particularly to the home environment, which is increasingly understood to be a significant setting for spread of Cryptosporidium infection. Further work on this would help support public health messaging on preventing spread of disease at home. Systematic review registration: PROSPERO number CRD42017056589.