PLOS Water
● Public Library of Science (PLoS)
Preprints posted in the last 30 days, ranked by how well they match PLOS Water's content profile, based on 13 papers previously published here. The average preprint has a 0.01% match score for this journal, so anything above that is already an above-average fit.
Justen, L. J.; Zulli, A.; Kantor, R. S.; Linfield, R. Y.; Moskatel, L. S.; Cunningham-Bryant, D.; Kaufman, J.; Johnson, M. C.; McLaren, M. R.; Sabeti, P.
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Wastewater metagenomic sequencing (WW-MGS) enables simultaneous detection of hundreds of pathogens, but its use for quantitative pathogen tracking has not been robustly validated. Like wastewater PCR (WW-PCR), WW-MGS is affected by biases from variable fecal dilution and sample processing, but must additionally contend with the compositional structure of sequencing data, where a taxon's apparent abundance depends on the abundance of every other taxon in the sample. Simple summaries such as a pathogen's fraction of total reads may therefore be poorly suited to quantitative use. We retrospectively evaluated seven normalization approaches that attempt to control for these sources of bias against a baseline of total read relative abundance, using 1,425 samples from the CASPER consortium spanning 25 U.S. sites. Each approach was compared against WW-PCR and clinical data across eight total pathogens. Among the normalization strategies we evaluated, tobamovirus markers, diet-derived plant viruses abundant in human stool, performed best. Normalizing WW-MGS data by tobamovirus-genus counts improved median site concordance for 18 of 19 pathogen and comparison-source combinations. Gains were largest for year-round-circulating SARS-CoV-2 and norovirus and smaller for sharply seasonal pathogens such as influenza and respiratory syncytial virus, where baseline concordance was already high. Tobamovirus normalization rarely degraded concordance, with median gains roughly five times larger than median losses. Tobamovirus-normalized WW-MGS reached clinical concordance comparable to targeted WW-PCR, supporting its use as a quantitative trend-monitoring tool alongside pathogen-agnostic detection.
Abba, O.; Mohammed, N.; Okoye, R.; Ukwaja, V. C.; Saidu, M.; Salisu, N.; Nyandjou, Y. M. C.; Abubakar, U.
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Background Cholera remains a recurrent public health emergency in Zamfara State, northwestern Nigeria, where communities depend predominantly on untreated and poorly protected water sources. Environmental water bodies serve as reservoirs for Vibrio cholerae, sustaining transmission cycles between outbreaks. Despite the severity of recurrent outbreaks in the region, data on the molecular characteristics and serogroup distribution of V. cholerae across different drinking water source types in Zamfara State remain critically limited. Methodology/Principal Findings A cross-sectional environmental surveillance study was conducted between 13 October and 26 November 2025 across five cholera-affected Local Government Areas (LGAs) of Zamfara State: Gusau, Bungudu, Talata Mafara, Zurmi, and Shinkafi. A total of 142 water samples were collected from five source types -- rivers, boreholes, wells, tap water, and sachet water. Presumptive isolation was performed on Thiosulfate-Citrate-Bile Salts-Sucrose (TCBS) agar following alkaline peptone water enrichment. Fifty-five presumptive isolates underwent PCR-based molecular confirmation and serotyping using three gene targets: ompW (species confirmation, 588 bp), ctxA (O1 toxigenicity marker, 302 bp), and tcpA (O139 colonisation factor, 120 bp). Presumptive V. cholerae was recovered from 55 of 142 samples (38.7%; 95% CI: 30.5-47.3%), with well water recording the highest positivity rate (69.7%; 95% CI: 51.3-83.7%). A statistically significant association was observed between water source type and presumptive V. cholerae occurrence ({chi}2 = 23.11, df = 4, p < 0.001). Molecular analysis confirmed 29 isolates (52.7%; 95% CI: 39.2-66.0%) as V. cholerae, comprising 22 O1 serotypes (75.9%), one O139 serotype (3.4%), and six non-O1/non-O139 serotypes (20.7%). Toxigenic O1 strains were detected across all five LGAs and in all five water source types, including commercially packaged sachet water. The O139 serotype was identified in a single well-water isolate from Zurmi LGA, representing the first environmental detection of this serotype in Zamfara State. Conclusions/Significance The co-circulation of toxigenic O1, O139, and non-toxigenic non-O1/non-O139 V. cholerae serogroups across five distinct drinking water source types confirms that community water environments serve as genetically diverse reservoirs sustaining cholera transmission in Zamfara State. These findings underscore the urgent need for integrated water quality surveillance, sanitation infrastructure investment, and sustained molecular monitoring of environmental V. cholerae populations.
Graham, S. S.; Wilkinson, C.; Briannae, T.; Williams, M.-J.; Tumin, D.
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Background: Helicobacter pylori is a major global pathogen with recognized potential for waterborne transmission. Intermittent water supply affects over one billion worldwide and may promote H. pylori contamination of municipal sources. Whether water supply discontinuity contributes to population-level H. pylori burden has not been examined globally. Materials and Methods: We conducted a cross-sectional ecological analysis of 79 countries with matched utility-level water infrastructure data and country-level H. pylori prevalence estimates from a published global meta-analysis. The primary exposure was continuity of water supply (hours/day). Secondary exposures included non-revenue water percentage (NRW %), pipe breaks per utility, and operating cost coverage ratio. Unadjusted and adjusted linear regression models with heteroscedasticity-consistent standard errors were estimated, controlling for basic sanitation coverage and log-transformed population density. A sensitivity analysis used a population-based measure of water availability on demand. Results: Greater water supply continuity was independently associated with lower H. pylori prevalence in both unadjusted ({beta} = -0.987, 95% CI -1.669 to -0.305, p = 0.005) and adjusted models ({beta} = -1.125, 95% CI -1.876 to -0.375, p = 0.004). Higher NRW % and lower operating cost coverage were each associated with higher H. pylori prevalence after adjustment. Pipe breaks were not significant in regression models though the Spearman correlation was in the expected direction. Sensitivity analysis produced consistent findings. Conclusion: IWS and broader water infrastructure deterioration are associated with higher H. pylori prevalence at the country level. These findings implicate water supply continuity as a potentially relevant environmental determinant of H. pylori transmission and suggest a role for water system investment within long-term gastric cancer prevention strategies.
Yao, X.; Otieno, D.; Geng, Q.; Brown, K. M.; Zhang, L.; McKay, R. M.; Lawal, O. U.
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Surface waters in urban watersheds receive episodic inputs of wastewater, runoff, and road-salt residues during spring, yet the contribution of these short hydrological windows to antibiotic resistance gene (ARG) loading remains poorly resolved. Weekly samples were collected from offshore and nearshore sites in the Detroit River, a Great Lakes transboundary connecting channel, from February to December 2025. Five clinically relevant ARGs encoding resistance to carbapenems, methicillin, and colistin, alongside the fecal marker pepper mild mottle virus (PMMoV), were quantified by qPCR and paired with ten conventional water-quality variables. blaNDM, mcr-1, and blaVIM-7 were not detected while blaKPC occurred as discrete pulses. One week (5 May) accounted for 37.2% of annual offshore blaKPC loading, and three weeks in late April to early May accounted for 72.8%, with peak concentrations reaching 5.4 x 10E3 and 7.2 x 10E3 copies/L. mecA was detected in nearly all samples without a dominant pulse. PMMoV normalization showed blaKPC did not vary seasonally (Kruskal-Wallis p = 0.198), consistent with diluted wastewater during spring precipitation events rather than an emergent source. mecA/PMMoV varied seasonally (p = 0.003) and was lowest in spring, implicating non-wastewater inputs in summer and autumn. Seven water-quality variables were significantly elevated during blaKPC pulse weeks. PCA distinguished pulse from background conditions, explaining 81.3% of variance. A random forest classifier achieved leave-one-out AUC of 0.917; ROC AUC reached 0.943 for total phosphorus, 0.924 for chloride, and 0.974 for the multivariate model. These results demonstrate that blaKPC and mecA operate through distinct source pathways and that routine water-quality monitoring can flag elevated blaKPC risk without additional sampling infrastructure.
Chipungu, J.; Ngosa, D.; Bick, S.; Davies, K.; Mwila-Kazimbaya, K.; Sharma, A.; Braun, L.; Chilengi, R.; Knee, J.; Dreibelbis, R.
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Food contamination contributes to 40% of childhood diarrhoea cases globally. It occurs when pathogens are transmitted from faecal matter to food through the faecal oral route. Food hygiene can prevent food contamination and improve the microbial quality of weaning foods in domestic settings. However, context specific evidence is needed to identify risk factors associated with food contamination, especially in complex low-income communities. Our study used a modified Hazard Analysis Critical Control Point approach to assess the quality of weaning foods and identify associated risk factors in a low income setting of Lusaka, Zambia. We enrolled 60 caregivers of children aged <1 year who had begun complementary feeding and collected data on household characteristics and food hygiene behaviours using surveys and structured observations. We collected samples of complimentary foods prepared for the child and tested them for Escherichia coli (E. coli) using the IDEXX Colilert-18 method. Multivariable logistic regression was performed to determine risk factors associated with food contamination. Of 59 food samples, 17 (29%) were contaminated with E. coli. Porridge (AOR = 0.04; 95% CI: 0.01, 0.28; p = 0.001) and non-animal source foods (AOR = 0.11; 95% CI: 0.02, 0.69; p = 0.019) were associated with lower odds of contamination compared with animal source foods. Heating of food was also associated with lower odds of contamination but was not significant. Food hygiene behaviours including utensil and surface cleaning were low (17% and 15%, respectively), and handwashing with soap before food preparation was not practiced. Our study identifies the microbiological risk associated with animal source foods and the potential health risk posed to weaning children. Nutrition guidelines should take into consideration this risk as programs promote an increased uptake of animal source foods in child diets.
Konyali, D.; Mayer, R. P.; Schubert, S.; Kneis, D.; Benisch, J.; Teran-Velasquez, G.; Erdem, E. D.; Tskhay, F.; Oertel, R.; Krebs, P.; Berendonk, T. U.; Klümper, U.
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Combined sewer overflows (CSOs) are a major pathway for untreated wastewater into urban streams, yet their role in shaping antimicrobial resistance (AMR) dynamics remains poorly understood. Here, we used high-frequency, time-resolved sampling during two storm-triggered CSO events across two monitoring locations and one stormwater-only control site in an urban stream to quantify how these disturbances affect microbial communities, antibiotic resistance genes (ARGs), and mobile genetic elements (MGEs) in an urban stream. CSO events caused rapid, up to two orders of magnitude, increases in bacterial, pathogen, and ARG abundance, with multiple transient peaks occurring within single overflow episodes. However, these increases were largely proportional to the total bacterial load, and most ARGs and MGEs did not change in relative abundance, indicating that CSOs primarily act as mass-transfer events rather than drivers of in situ selection. Downstream attenuation was governed by hydrological dilution despite additional CSO inputs: Both microbial and resistance signals largely returned to baseline within short time frames. This demonstrates that CSOs function as hydrologically driven pulse disturbances that generate acute but transient AMR exposure. Because CSO events lack the sustained pressure associated with continuous wastewater discharges, rapid washout prevents the long-term establishment of sewage-derived resistance. These findings highlight that AMR risk in CSO-impacted systems is driven primarily by short-term exposure rather than by persistent ecological transformation, with important implications for urban water management under increasingly extreme rainfall conditions.
Tseitlin, M.; Garcia-Giron, J.; Crabot, J.; Jiang, X.; Larkin, D. J.
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Freshwater monitoring programmes like the European Unions Water Framework Directive (WFD) provide a wealth of data on European lake status, including water quality and macrophytes (aquatic plants) as critical habitat features that support health of humans and wildlife. Easier WFD data access can enable external management and research to better safeguard human and natural freshwater use. We demonstrate a replicable workflow to easily download and process multi-year (2007-2024) observations of lake macrophytes (425 sites) and complementary water quality variables (202 sites) from Swedish WFD data. Then, we illustrate the value of improved data access to address ecological questions that drive conservation, investigating how spatial scales influence macrophyte richness and associated water quality relationships using a spatial random intercept model. Decomposing the spatial intercept links small scales (<10 km) to site-level gradients and large scales (>100 km) to biogeographical drivers. Stochastic and environmentally-structured processes coexisted at intermediate scales (10-100 km). Adding water quality rarely improved overall predictive performance of macrophyte diversity models but consistently influences the role of different spatial scales. Water quality variables showed consistent spatially structured variation at intermediate scales and unique spatial patterns in tandem, overlapping with large-scale biogeographical influences. Altogether, we show context-dependencies for spatial model interpretation and provide guidance in accounting for spatial confounding to improve inferential and predictive performance. Our workflow and results show a clear way forward for accessing high-quality macrophyte and water quality data sets and their utility for addressing ecological questions that guide macrophyte protection under the WFD. HighlightsO_LIyears Swedish of macrophyte and water quality monitoring data were extracted. C_LIO_LIrichness showed scale-specific patterns linked to geographic gradients. C_LIO_LIbest predictive models for richness had no water quality at all. C_LIO_LIoverlap in their spatial scales and must be carefully separated. C_LIO_LIpen access data and multiscale analysis can apply to many ecological questions. C_LI
Addison-Turner, D. C.; Daily, G. C.
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Introduction: Climate change disproportionately affects disadvantaged communities, yet construction workforce education rarely addresses interconnected pathways linking energy efficiency, nature exposure, and public health. Green-blue infrastructure delivers co-optimized benefits: reducing building energy consumption 15-30% while decreasing heat-related mortality by approximately 3.9% per degree Celsius of urban cooling (Gasparrini et al., 2017) -- epidemiological benchmarks that inform the dose-response functions embedded in the Ecosystem Justice Translator (EJT). This protocol describes, to our knowledge, the first randomized controlled trial evaluating a curriculum intervention designed to develop planetary health competencies and environmental justice awareness among high school students pursuing construction careers. Methods and analysis: This two-arm, parallel-group randomized controlled trial targets enrollment of N=200 high school students (ages 14-18) from construction career pathway programs in the San Francisco Bay Area (over-recruitment target N=250; 25% buffer for attrition). Students are individually randomized 1:1 to intervention (Community-Centered Design curriculum integrating the Ecosystem Justice Translator) or control (traditional Virtual Design and Construction curriculum), stratified by school site using block randomization. The 6-month intervention features the Ecosystem Justice Translator (EJT) -- a computational system using large language models to translate community health equity concerns into quantifiable investment priorities. The EJT's 51-theme health equity taxonomy was derived from validated public health frameworks (Centers for Disease Control and Prevention [CDC] Social Vulnerability Index, Environmental Protection Agency [EPA] EJScreen, Healthy People 2030). Primary outcome is Health-Integrated Equity Consciousness Index (HI-ECI), measured at baseline, 3, 6 (primary endpoint), and 12 months. Analysis uses intention-to-treat linear mixed-effects models with random intercepts for participants. The minimum required sample (n=26 per arm; G*Power, two-tailed a=0.05, 80% power, Hedges' g=0.80) is exceeded by enrolled N=200, which provides >99% power at Hedges' g=0.80 and supports multi-site confirmatory factor analysis. Ethics and dissemination: This protocol has been approved by Stanford University Institutional Review Board (IRB eProtocol #84369, approved February 13, 2026). Parental consent from a parent or guardian and written assent from each student participant are required prior to enrollment. All instruments, curriculum materials, and EJT source code will be released open-source under CC BY-NC-SA 4.0, permitting free use for educational, research, and non-profit purposes, concurrent with primary publication. Commercial licensing may be pursued separately through Stanford University Office of Technology Licensing (OTL docket S25-565). Trial registration: ClinicalTrials.gov NCT07315919. Pre-results. Protocol version 4.0, June 2026.
Lee, J.; Gonzalez, C.; Au, E.; Acosta, N.; Waddell, B. J.; Xu, Z. S.; Clark, R. G.; Weyant, R. B.; Dalton, B.; Zaheer, R.; McAllister, T. A.; Barkema, H.; Nobrega, D.; Bhatnagar, S.; Lee, B. E.; Pang, X.; O'Grady, C.; Frankowski, K.; Bertazzon, S.; Conly, J. M.; Hubert, C. R. J.; Parkins, M. D.
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Antimicrobial resistance (AMR) is an ever-increasing threat to population health. Industrial, environmental and societal factors are increasingly recognized as important contributors to AMR within communities. Here, we investigated the spatial distribution of AMR genes (ARGs) across Alberta, Canada and their association with socio-economic, immigration-related, and agro-industrial characteristics using municipal wastewater-based surveillance. We analyzed monthly wastewater metagenomes collected between March 2022 and March 2023 across eleven municipalities, representing 39% of Alberta's population. Integration with census data enabled multivariate analysis, revealing that municipal resistome profiles were strongly structured along income and immigration-related population gradients. ARGs spanning 14 resistance classes exhibited distinct distributional patterns across income and immigration gradients, including contrasting associations among beta-lactam, aminoglycoside, and macrolide-lincosamide-streptogramin ARGs, consistent with heterogeneous selection pressures across sub-populations. These findings demonstrate the capacity of longitudinal wastewater surveillance to identify persistent population-level resistome patterns and highlight the importance of incorporating sociodemographic context into AMR surveillance and mitigation strategies.
Alemu, R.; Tafere, K.; Gashu, D.; Joy, E. J. M.; Bailey, E. H.; Lark, R. M.; Broadley, M. R.; Masters, W. A.
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The introduction of salt iodization is associated with improved health and socioeconomic outcomes, but is not yet universally adopted and not always sustained. Using a quasi-experimental event study with difference-in-differences over space and time, we quantify the impacts of iodine deficiency in utero and infancy on childhood mortality and later academic achievement in Ethiopia, comparing cohorts born just before and after the May 1998 border closure that interrupted access to iodized salt. Rural children with fewer months of early-life exposure to iodized salt scored lower on standardized secondary-school exams, especially in districts with low environmental iodine, with excess deaths emerging in infancy and persisting through early childhood. These findings reveal the long-term benefits of salt iodization for health and education, especially for people with low intake of iodine from environmental sources.
Sgarabotto, E.; Tiwari, A.; Kabena, M.; Lyimo, E.; Lompo, P.; Shea, D.; Ngelesi, E.; Mushumbusi, J. P.; Zakaria, G.; Msoma, E.; Kabore, B.; Mnyawonga, S. C.; Yougbare, S.; Chuwa, M.; Tran, T. T.; Salmivirta, E.; Miller, T.; Rytkonen, A.; Lood, R.; Krolicka, A.; Tahita, M. C.; Baraka, V.; Maketa, V.; Pitkanen, T.
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The emergence of the novel monkeypox virus (MPXV) clade Ib in the Democratic Republic of the Congo (DRC) and neighboring countries in late 2023 highlighted the need for rapid, scalable surveillance approaches to support outbreak detection and response. As part of the ODIN-Mpox project, wastewater surveillance (WWS) systems were established as an emergency public health measure in three Sub-Saharan African countries (DRC, Tanzania, and Burkina Faso) to evaluate the feasibility of wastewater-based monitoring for mpox and strengthen local surveillance capacity. Between January 2025 and April 2026, 117 wastewater samples were collected from selected sites and analyzed for MPXV DNA using targeted qPCR assays. Clinical mpox data were obtained from national surveillance systems and WHO reports to assess epidemiological linkages between wastewater detections and reported infections. Six wastewater samples tested positive for MPXV DNA. During the study period, DRC experienced the highest disease burden, with weekly reported cases peaking at about 3,000 in January 2025, while Tanzania reported a peak of 20 weekly cases in March 2025. No confirmed clinical cases were reported in Burkina Faso. No clear relationship was observed between reported case numbers and qPCR Ct values in positive wastewater samples. Despite the low detection frequency, the project demonstrated the operational feasibility of implementing MPXV wastewater surveillance in resource-limited settings and established laboratory capacity for environmental monitoring of emerging infectious diseases. Given the early stage of WWS implementation in the region, the study identified opportunities for further system strengthening, including optimization of sample processing and reporting workflows, improved access to laboratory supplies, and enhanced integration of environmental and clinical surveillance data streams. These findings highlight the value of WWS as a complementary component of integrated public health surveillance systems and emphasize the need for continued investment in laboratory capacity, harmonized methodologies, governance frameworks, and knowledge exchange to enhance outbreak preparedness and response in low-resource settings.
Omari, P. K.; Ondicho, Z. M.; Karanja, S. M.; Mambo, S. N.
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Diarrheal disease remains a leading cause of morbidity and mortality among children under five globally, with poor sanitation and hygiene accounting for over 88% of diarrhea and malnutrition burden. In Kenya, diarrhea ranks third in under-five mortality, particularly affecting arid and semi-arid regions. School-Led Total Sanitation (SLTS), adapted from Community-Led Total Sanitation (CLTS), uses pupils as change agents for household hygiene knowledge transfer. However, SLTS effectiveness in addressing diarrhea and malnutrition has not been evaluated in Kenya. This study assessed SLTS effects on diarrheal disease and nutritional outcomes among children aged 5-59 months in Baringo County. A pre- and post-test quasi-experimental design with nonequivalent control groups was employed in Mogotio (intervention) and Baringo South (control) sub-counties. Using multistage sampling, 440 children aged 6-59 months were enrolled. The six-month SLTS intervention included capacity building, school health club formation, triggering activities using Participatory Rural Appraisal tools, Information, Education, and Communication materials distribution, continuous sensitization, and household monitoring. Data were collected at baseline and three months post-intervention using electronic questionnaires and anthropometric measurements. Nutritional status was assessed using WHO Anthro software z-scores for length/height-for-weight (HWZ), and weight-for-age (WAZ) to determine wasting, and underweight prevalence. Chi-square analysis assessed intervention-control differences. Baseline and endline socio-demographic characteristics were comparable between groups. At endline, no significant nutritional outcome differences were observed: wasting prevalence was at 15.0% versus 16.4% ({chi}{superscript 2}=0.155, df=1, p=0.694) while underweight was 12.3% versus 13.6% ({chi}{superscript 2}=0.181, df=1, p=0.670). However, diarrheal disease prevalence significantly reduced in intervention versus control groups: 5.9% versus 13.2% ({chi}{superscript 2}=6.738, df=1, p=0.009), representing a 53% reduction. SLTS intervention showed no significant effect on nutritional outcomes but demonstrated a significant reduction in diarrheal disease among children aged 6-59 months. These findings provide strong evidence for integrating school-based sanitation and hygiene approaches into broader public health strategies addressing diarrheal diseases.
Bamgboye, E.; Adeleke, M. A.; Surakat, O.; Mhlanga, L.; Fasasi, K.; Rufai, A. M.; Popoola, K. O.; Aminu, U. M.; Ogbulafor, N.; Ozodiegwu, I. D.
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Larval source management (LSM) is a complementary malaria control intervention, yet evidence to guide context-specific implementation remains limited. Nigeria's recent national commitment to LSM scale-up makes the need for operational evidence particularly urgent. Informal settlements embedded within wards of differing dominant settlement archetypes may present distinct Anopheles larval habitat profiles with implications for how LSM strategies should be tailored. We evaluated Anopheles larval habitats within informal settlement areas across wards with contrasting settlement archetypes in Ibadan metropolis, Nigeria, to inform targeted larval source management. Potential breeding habitats were surveyed in dry and wet seasons within informal settlement areas across three wards -- Olopomewa, Challenge, and Agugu -- representing formal, informal, and slum settlement-dominant archetypes respectively. Habitats were characterized and assessed for Anopheles larval presence. Pareto analysis identified habitats accounting for 80% of larval abundance. Breeding habitat density per km{superscript 2} was estimated using a simulated pathway technique. Associations between mosquito dispersal scale and household malaria infections identified through Rapid Diagnostic Testing were evaluated using kernel-based distance-decay weighting. Environmental drivers of habitat suitability were modeled in MaxEnt. Of 420 potential breeding habitats identified, 31 (7.4%) contained Anopheles larvae, predominantly during the wet season (26, 83.9%). Puddles, dug wells, drainages/gutters/ditches and canals accounted for 80% of site-level larval abundance when standardized by sampling effort. Larval and breeding habitat density were highest in Agugu, the slum-dominant ward, across both seasons. Modeled mosquito dispersal scale showed best fit at 30-32m in Challenge (OR 1.41, 95% CI: 1.05-1.89) during the wet season and 16-18m in Agugu (OR 1.29, 95% CI: 1.04-1.60) during the dry season. Habitat suitability in Agugu was higher farther from large water bodies and in areas with higher population density and positive Normalized Difference Water Index values. In Challenge, suitability was higher in areas with lower nighttime light levels, positive Normalized Difference Water Index values, and negative Normalized Difference Moisture Index values. Further studies incorporating multiple wards across diverse urban settings are needed to determine whether differences in larval ecology between settlement archetypes provide a reliable basis for planning larval source management.
Darling, A.; Sastry, S.; Bowie, K.; Luhung, I.; Franklin, A.; Morley, V.; Stephenson, N.; Katz, D.; Gratalo, D.; Simas, A.; Burke, T.; Ruedaflores, M.; Roberts, S.; Turner, P.; Martinello, R.; Peccia, J.; Healy, H. G.
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Wastewater surveillance (WS) has been widely adopted as a cost-effective and population-representative infectious disease monitoring tool and is increasingly being applied to bacterial and antimicrobial resistance gene (ARG) targets. However, some of these targets may persist in pipe biofilms and detach into wastewater, complicating accurate WS interpretation. To investigate biofilm contributions to wastewater pathogen and ARG signals, paired sink-drain biofilm, branch-drain-plumbing biofilm (sewer biofilm), and wastewater were collected from five hospital sites over a four-month period and analyzed using 16S rRNA gene amplicon sequencing and probe-capture metagenomics. Overall, sewer biofilm bacterial communities were as diverse as wastewater. Across sites, a mean of 9% (0.9 to 23.3%) of wastewater bacterial communities could be attributed to sewer biofilm communities. Many clinically relevant pathogens were consistently detected both in sewer biofilm and wastewater, including environmentally persistent and/or biofilm-associated taxa (e.g., Pseudomonas aeruginosa, Klebsiella pneumoniae). While many ARGs overlapped between wastewater and biofilms (e.g., tetA, sul1, blaCTX-M, vanA), others were significantly enriched in sewer biofilms (e.g., qacL, van-operon and OXA genes). Together, these findings confirm that wastewater pathogen and resistome profiles integrate inputs from both human shedding and pipe-resident communities and therefore need to be considered when selecting WS targets and interpreting signal.
Boote, H.; Coyle, N. M.; Forde, A.; Alexa, I.; Burchell, M.; Reynolds, S.; Studholme, D. J.; Wagley, S.
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Climate-driven increases in sea surface temperature have been associated with the expansion of Vibrio species and a corresponding rise in vibriosis cases in both human populations and aquaculture systems. Coastal waters across the south of England are increasingly becoming suitable for the growth and establishment of both human- and aquaculture-associated Vibrio species, potentially increasing vulnerability to the types of infections and disease outbreaks already reported elsewhere in the world. In this study, we report the presence of a diverse and well-established Vibrio community within the Teign Estuary, (Southwest, UK), including the human-pathogenic species V. parahaemolyticus, V. cholerae (non-O1/non-O139), V. alginolyticus, and V. diabolicus, as well as the important aquaculture pathogens V. jasicida, V. aestuarianus, and V. anguillarum. We identified V. diabolicus, a species that was indistinguishable from V. alginolyticus using conventional biochemical identification methods and could only be accurately resolved by whole-genome sequencing and developed novel PCR targets to differentiate these species in the lab. Using the insect infection model Galleria mellonella, we demonstrate that environmental isolates of V. cholerae (non-O1/non-O139), V. parahaemolyticus, and V. alginolyticus possess virulence potential. We also investigated the effects of sewage effluent on the growth of Vibrio isolates from the Teign Estuary and found that sewage can preferentially promote the growth of Vibrio species. Furthermore, several Vibrio isolates were multidrug resistant and carried antimicrobial resistance genes, highlighting the potential role of environmental Vibrio populations in the Teign Estuary as reservoirs of antimicrobial resistance. Together, these findings demonstrate how rising sea surface temperatures and sewage pollution may influence the emergence, persistence, and public health and aquaculture significance of Vibrio species in UK coastal waters.
Joseph, S. A.; Opara, C.; Shanahan, M. R.; Varga, J.; Falcon, J.; Ibanga, U.; Venkatraman, S.; Perlstein, M.; Jang, T. L.; Golombos, D.; Ghodoussipour, S.; Fan, T.; O'Leary, S.; Graber, J. M.; Hart, J. E.; Barrett, E. S.; Bandera, E. V.; Iyer, H. S.
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Background: Men with prostate cancer (PCa) may be especially vulnerable to per- and polyfluoroalkyl substances (PFAS) exposure due to their endocrine-disrupting and cardiometabolic impacts and cardiotoxicity and immune suppression of treatments. Objective: A pilot study was launched to measure serum and tap water PFAS concentrations in PCa survivors. Methods: Men with PCa were recruited from Rutgers Cancer Institute between February 2025 and March 2026, with ongoing enrollment and follow-up. Eligible men were aged [≥]40 years and either on active surveillance or within 3-12 months of initial definitive treatment. Participants provided blood and residential tap water samples, which were analyzed using mass spectrometry (serum) and modified EPA method 537 (water). Geometric means were used to summarize PFAS concentrations by race and assess serum-tap water correlations. Results: Of 235 eligible patients, 124 (60%) enrolled. Median age was 64 years; 63% were non-Hispanic White, 43% had a Gleason score [≤]6. Roughly half of participants provided serum and/or tap water samples. In serum, six PFAS analytes had >80% detection; of these analytes, median concentrations ranged from 0.13 ng/mL (IQR: 0.07-0.20) for PFHpS to 2.55 ng/mL (IQR:1.54-3.82) for nPFOS. Among 74 tap water samples, 9 PFAS analytes had >60% detection; of these, median concentrations of PFNA (0.56 ng/L; IQR: 0.33-0.75), PFOA (3.75 ng/L; IQR: 1.21-5.27), and PFOS (2.29 ng/L; IQR: 0.46-2.89), were below New Jersey Maximum Contaminant Levels. Non-White participants had significantly higher levels of multiple PFAS analytes in both serum and tap water. Serum-tap water correlations were modest (r=0.22-0.41). Significance: The pilot study has demonstrated both the feasibility and importance of studying PFAS exposure pathways as well as potential impacts of PFAS exposure in diverse populations. Keywords: Prostatic Neoplasms, Per- and Polyfluoroalkyl Substances (PFAS), Biomonitoring, Environmental Exposure, Cohort Studies, Pilot study Impact Statement: This study provides some of the first estimates of PFAS exposure among prostate cancer patients in serum and tap water, showing moderate correlations between tap water and serum concentrations of specific PFAS analytes. These findings can support larger studies to identify environmental exposure sources and evaluate the role of PFAS in prostate cancer progression and outcomes.
Kyereh, F. K.; Ohemeng, A. N.; Engle-Stone, R.; Wessells, K. R.; Kumordzie, S. M.; Arnold, C. D.; Davis, J. N.; Becher, E. R.; Fuseini, A. D.; Nyaaba, K. W.; Tan, X.; Vosti, S. A.; Adu-Afarwuah, S.
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Background: Monitoring urinary iodine concentration (UIC) after sustained exposure informs iodine delivery strategies. We aimed to compare endline UIC among women of reproductive age (WRA) and preschool children (PSC) receiving multiple micronutrient-fortified (MMF) vs. iodine-only bouillon, and to describe population iodine status at baseline and endline. Methods: This pre-specified secondary outcome analysis used Condiment Micronutrient Innovation Trial (CoMIT) data. Non-pregnant, non-lactating WRA (15-49 years) and PSC (2-5 years) were enrolled at the household level. Households received MMF or iodine-only bouillon for 9 months (38 weeks); both contained iodine (KIO3) at 30 ug/g. Baseline and endline UIC (ug/L) were measured by modified Sandell-Kolthoff reaction in spot urine samples. ANCOVA models, adjusted for baseline log-UIC and recruitment site, compared endline geometric mean UIC between trial arms. Median UIC at both timepoints was compared to WHO cut-offs (ug/L): <100 (insufficient), 100-199 (adequate), 200-299 (above requirements), and >=300 (excessive); the prevalence of UIC <50 ug/L was calculated. Results: Endline UIC data were available for 611 WRA and 630 PSC. Adjusted endline UIC did not differ by arm (geometric mean ratio [95% CI]: WRA 0.97 [0.86-1.10]; PSC 0.96 [0.84-1.10]). With arms combined, median UIC increased among WRA (100.5 to 124.6 ug/L) and PSC (109.6 to 136.9 ug/L), with fewer samples <50 ug/L at endline. Conclusions: Adjusted endline UIC did not differ between trial arms. After 9 months' use of iodine-fortified bouillon, median UIC remained adequate among WRA and PSC, with fewer samples <50 ug/L at endline.
Müller-Hauser, A. A.; Lambrecht, N. J.; Sobhan, S.; Waid, J. L.; Huda, T. M. N.; Nurjadi, D.; Wendt, A. S.; Rahman, M.; Gabrysch, S.
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Background: Repeated enteric infections and chronic enteric dysfunction have been associated with undernutrition in children. Interventions that reduce enteric pathogen exposure in young children could thereby improve growth and developmental outcomes. We assessed enteric pathogen prevalence in Bangladeshi infants, the impact of a combined homestead food production and food hygiene intervention on pathogen infections, and associations between pathogen infections, enteric dysfunction markers, and child growth outcomes. Methods: We analyzed panel data from 231 children born between April and December 2018 within the Food and Agricultural Approaches to Reducing Malnutrition (FAARM) cluster-randomized trial in Sylhet, Bangladesh. Stool samples were collected at 0-3, 6-8, and 10-13 months of age and assessed for enteric dysfunction biomarkers (myeloperoxidase, alpha-1 antitrypsin, and neopterin) by ELISA and 14 enteric pathogens by multiplex RT-PCR. Diarrhea prevalence was recorded using 7-day recall. Child length and weight were measured at birth and trial endline. Multilevel regression assessed the intervention effect and quantified associations between pathogen exposure, enteric dysfunction, and growth outcomes. Findings: Enteric pathogen prevalence was high (84%) despite low 7-day diarrhea prevalence (5%), and co-infections were common. There was no intervention effect on the prevalence of enteric pathogens. Shigella spp. and Giardia lamblia were associated with higher myeloperoxidase concentrations, while sapovirus was associated with higher alpha-1 antitrypsin concentrations. Repeated protozoan infections (mainly Giardia lamblia) were associated with lower length-for-age, while repeated viral infections (mainly rotavirus and sapovirus) and Cryptosporidium infections were associated with lower weight-for-height and weight-for-age. There was marginal evidence that bacterial infections were associated with lower length-for-age. Conclusion: The intervention was insufficient to reduce the high burden of enteric pathogens in infants, and subclinical infections were associated with enteric dysfunction and poorer growth outcomes. Comprehensive strategies addressing all key exposure pathways are needed to limit pathogen infections and their consequences for child development.
MBUGUA, S. M.; Kongere, J.; Kagaya, W.; Mwaura, P.; Ko, Y.; Omondi, P.; Mujuni, M.; Kasililika, A.; Kisiangani, I.; Kanoi, B. N.; Kaneko, A.; Gitaka, J.
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Malaria transmission has been reduced considerably in some Kenyan regions; however, it remains high in the Lake Victoria basin. Ceiling nets fall under house screening as interventions in vector control under the World Health Organizations Guidelines on Malaria and has a conditional recommendation with low-to moderate-certainty evidence of impact against malaria. This study aimed at assessing the perceptions of health system managers on the health system readiness in integrating ceiling nets into malaria vector control in and implementation pathways.A cross-sectional, qualitative, action research design was used aimed at providing actionable solutions to health systems challenges in the inclusion of ceiling nets as a complementary vector control strategy in the comprehensive approach on malaria prevention in Suba West sub-county, Homa Bay county. Key-informant interviews on perspectives on health system readiness for ceiling net integration into routine programmatic vector control strategies were conducted among health system managers. Qualitative data was captured using audio tapes and field notes, transcribed and analyzed using case-based in-depth inductive and deductive analysis using a thematic framework to classify and organize data into themes.Key emergent themes included perception and experiences in malaria vector control strategies, role of community health in malaria vector control strategies, systemic barriers and facilitators in malaria vector control, perspectives on integration of the ceiling nets in malaria vector control. This study demonstrates that health system managers perceive ceiling nets as a feasible, acceptable, and operationally integrablecomplement to existing malaria vector control strategies, while also identifying concrete system bottlenecks that must be addressed for scale-up. The ceiling nets showed high acceptability, appropriateness of fit in structurally heterogenous housing structures and high feasibility as an addition to a comprehensive complementary vector control strategy.The findings inform decision-ready implementation pathways of complementary ceiling nets in existing vector control strategies. Ceiling nets are perceived by frontline health system managers as a system-ready, acceptable house-modification intervention that can close critical protection gaps left by bed-net-centric malaria control, provided community health platforms and supply chains are deliberately leveraged. Successful scale up implementation hinges on a structured approach of integration that includes community buy-in, task-shifting of community health promoters in ceiling net installation, effective supply chains, and robust monitoring and evaluation systems to track, maintain and assess system level indicators and community level indicators.
Fernandez, S. P.; Rojas, L. M.; Gomez, J.; Sandoval-Bances, J.; Condori-Catachura, S.; Garcia, P. D.; Abrams, S.; Anthierens, S.; Bastiaens, H.; Chenet, S. M.; Delgado-Ratto, C.
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Background The COVID-19 pandemic was associated with reported disruptions to healthcare delivery and malaria control activities in remote, malaria-endemic indigenous communities with limited access to healthcare. Remote indigenous communities in the Peruvian Amazon may have been especially vulnerable due to interruptions in malaria surveillance, diagnosis, and treatment. We investigated the impact of the COVID-19 pandemic on malaria burden, healthcare access, and community perceptions in hard-to-reach indigenous communities in the Amazonas region of Peru. In malaria-endemic regions, these lessons are particularly important because future health emergencies may similarly affect surveillance, diagnosis, prevention, and treatment activities, potentially reversing gains achieved through malaria control programs. Methods A convergent parallel mixed-methods study was conducted in 2021 and 2022 across four indigenous communities in the Rio Santiago district, Amazonas region, Peru. Quantitative data were collected through cross-sectional malaria surveys, and qualitative data were obtained through semi-structured interviews with inhabitants, community health workers, and local health personnel. Malaria infections were detected by microscopy and confirmed by PCR. Factors associated with the occurrence of malaria infection were studied based on a generalized estimating equation (GEE) approach applied to clustered binary outcome data and accounting for repeated observations within participants across study years. Qualitative data were analyzed thematically, and both components were integrated using the Pillar Integration Process framework. Results A total of 514 participants were included. PCR-based malaria prevalence was 17.6% in 2021 and 26.09% in 2022. P. falciparum prevalence was particularly high in the Alianza Progreso community (2021: 24.19%, 2022: 16.16%) compared to the other studied communities. Previous malaria infection and chills were associated with PCR-confirmed malaria infection. Qualitative findings indicated that COVID-19-related disruptions affected malaria control activities by interrupting diagnosis and treatment availability, reducing community follow-up, and prioritizing COVID-19 response activities over malaria control. Participants also described fear of COVID-19, temporary migration to farm areas, and reliance on herbal medicine during the pandemic. Conclusions The COVID-19 pandemic may have contributed to exacerbated pre-existing challenges to malaria control in remote indigenous communities in the Peruvian Amazon. Strengthening malaria surveillance, ensuring continuity of diagnosis and treatment, and improving healthcare access in geographically isolated communities will be critical to supporting malaria elimination efforts in Peru.