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As a 2010 earthquake and cholera response project, in 2013–2014, an international non-governmental organization, working with local organizations, installed water systems in two Haitian communities. In 2016, 2 years after installation, we conducted a mixed-methods evaluation to assess sustained effectiveness, including 20 infrastructure assessments, 199 household surveys, water quality testing, 30 key informant interviews, and financial analysis of two water committee records. One of 14 (7.1%) installed kiosks were functional during the evaluation, with 42–60% of survey respondents near installed sources reporting using system water for drinking. No household water sample had detectable chlorine residual and non-detectable E. coli, except when household water treatment was reported. Informants expressed appreciation for the project, and discussed difficulties with operations, maintenance, and community engagement. Revenue was initially sufficient for operations and maintenance, although not sustainable because lack of trust led to poor quality service and then lack of payment. While the functional kiosks did provide water to some residents, overall project sustained effectiveness was not reached due to operational and maintenance issues, and lack of governance and community engagement. We recommend future implementers of small-scale water systems in complex contexts like Haiti plan for the technical and social components necessary for sustained effectiveness.

Background Diarrhoea is one of the leading causes of disability-adjusted life years (DALYs) among children below five years, though the proportion of the burden occurring amongst those aged over 70 is increasing. The cost of treating and managing diarrhoea can place a burden on individuals, their households, and society in general. The cost can be high but is often undocumented, and many studies focus on children or hospitalised patients only. This study aimed to estimate the economic cost per case of diarrhoea amongst individuals of any age in Uvira, Democratic Republic of the Congo.Methods The study was cross-sectional and retrospective, and based on a household survey approximately representative of the city undertaken in September 2021. Data on quantities and prices of resources were collected in the survey, as well as interviews with staff at the Cholera Treatment Centre in the Uvira general hospital and their records on resource use and patient numbers. Direct and indirect costs were measured from the societal perspective, and multiple linear regression used to identify cost drivers.Results Of 2,820 members of the 528 households surveyed, 175 people (6.2%) were reported to have had diarrhoea in the previous seven days. The majority sought care (86%) of which most (63%) visited a pharmacy. The average economic cost of illness (COI) for an episode of diarrhoea was 33,366 Congolese Francs (CDF) (US$ 16.8). The median was CDF 14,000 (US$ 7.0). The average out of pocket financial COI to patients was CDF 15,111 (US$ 7.6), representing 9% of the estimated average monthly income of households. On average caregivers and patients lost 4 days per episode. A concentration index suggested a lower economic COI among poorer households (p = 0.096). A regression analysis identified that being older than 5 years or being water insecure (p = 0.029) were associated with higher COI.Conclusion Households in Uvira experience many diarrhoeal episodes per year, and the COI is an important burden for them and society. These costs could be avoided if diarrhoea were prevented through public health interventions, and if care-seeking was better managed to ensure appropriate treatment.

Children under-five years of age are particularly vulnerable to severe acute malnutrition (SAM), and the risk factors associated with relapse to SAM are poorly understood. Possible causes are asymptomatic or symptomatic infection with enteric pathogens, with contaminated food as a critical transmission route. This cross-sectional study comprised a household survey with samples of child food (n=382) and structured observations of food preparation (n=197) among children aged 6-59 months that were discharged from treatment in community management of acute malnutrition (CMAM) programmes in Aweil East, South Sudan. We quantifiedEscherichia coliand total faecal coliforms (TFCs), measured in colony forming units per g of food (CFU/g), as indicators of microbial contamination of child food. A modified hazard analysis critical control point (HACCP) approach was utilised to determine critical control points (CCPs) followed by multivariate logistic regression analysis to understand the risk factors associated with contamination. Over 40% of samples were contaminated withE. coli(43% >0E. coliCFU/g, 95%CI 38-48%), and 90% had >10 TFCs (CFU/g) (>10TFC CFU/g, 95%CI 87-93%). Risk factors associated (p

Improvements in water and sanitation should reduce cholera risk. But it is unclear which water and sanitation access are associated with cholera risk. We estimated the association between eight water and sanitation measures and annual cholera incidence access across sub-Saharan Africa (2010-2016) for data aggregated at the country and district-level. We fit random forest regression and classification models to understand how well these measures combined might be able to predict cholera incidence rates and identify high cholera incidence areas. Across spatial scales, piped or “other improved” water access was inversely associated with cholera incidence. Access to piped water, piped sanitation, and piped or “other improved” sanitation were associated with decreased district-level cholera incidence. The classification model had moderate skill in identifying high cholera incidence areas (cross-validated-AUC 0.81 95%CI 0.78–0.83) with high negative predictive values (92.5–100.0%) indicating the utility of water and sanitation measures for screening out areas that are unlikely to be cholera hotspots. While comprehensive cholera risk assessments must incorporate other data sources (e.g., historical incidence), our results suggest that water and sanitation measures could alone be useful in narrowing the geographic focus for detailed risk assessments.SynopsisWe quantified the relationship between high-resolution estimates of water and sanitation access and cholera incidence and assessed the utility of water and sanitation measures in identifying high risk geographic areas in sub-Saharan Africa.

BackgroundAntibiotic resistance is a leading cause of death, with the highest burden in low-resource settings. There is limited evidence on the potential for water, sanitation, and hygiene (WASH) infrastructure to reduce the burden of antibiotic resistance in humans.MethodsWe used geospatially tagged human gut metagenomes and household survey datasets to determine the association between antibiotic resistance gene (ARG) abundance and community-level coverage of improved drinking water points and improved sanitation facilities. Adjusted general linearized models with robust standard errors were used to estimate the relationship between ARG abundance in the human gut and access to water and sanitation.FindingsWe identified 1589 publicly available metagenomes from 26 countries. The average abundance of ARGs, in units of log10 ARG reads per kilobase per million (RPKM) mapped reads classified as bacteria, was highest in Africa compared to other World Health Organization (WHO) regions (one-way ANOVA pInterpretationWhile additional studies to investigate casual effects are needed, increasing access to water and sanitation could be an effective strategy to curb the proliferation of antibiotic resistance in low- and middle-income countries.FundingBill & Melinda Gates FoundationResearch in ContextEvidence before this studyAntibiotic resistance is a growing global health threat that disproportionately affects low- and middle-income countries (LMICs). In 2019, an estimated 5 million deaths were associated with antibiotic resistance, with the highest death rate in western sub-Saharan Africa. Water, sanitation, and hygiene (WASH) interventions (e.g., household drinking water treatment, flush toilet, hand washing facilities with soap) can reduce diarrheal and respiratory infections, as reported in previous meta-analyses. Estimates, based on probability modeling, suggest improvements in water and sanitation could decrease antibiotic use for diarrheal disease treatment by 47-50% and 69-72%, respectively. Improving WASH infrastructure could theoretically contribute to the control of antibiotic resistance by preventing the release of antibiotics, resistant organisms, or antibiotic resistance genes (ARGs) into the environment, thus decreasing the burden of antibiotic-resistant infections. One global analysis across 73 countries suggested that improved infrastructure, including WASH services, was associated with reduced antibiotic resistance prevalence in isolates, however the independent effect of WASH access was not assessed.We searched PubMed for evidence on the impact of WASH interventions (excluding those related to animals and agriculture) on antibiotic resistance using the following keyword chain: (water OR sanitation OR hygiene OR WASH) AND (antimicrobial OR antibiotic) AND resistance) NOT (“OneHealth” OR “One Health” OR animal OR livestock). We selected reviews and systematic reviews (n=1420) to be screened for relevance to WASH and antibiotic resistance. The reference lists of included reviews were then searched for individual studies. We also consulted international agency guidelines and online resources from the Joint Programming Initiative on Antimicrobial Resistance, the International Scientific Forum on Hygiene, ReAct, Resistomap, and the London School of Hygiene and Tropical Medicine AMR Centre.Studies focusing on centralized water or wastewater treatment technologies in high income countries (HICs) reported variable removal of antibiotics (53 to >90%), antibiotic-resistant bacteria (90-99.9%) and ARGs (90-99.9%) from waste streams. Other studies were conducted on hand hygiene, which has proven effective at reducing human infections and antibiotic use. No studies were identified on the effect of on-site sanitation systems (e.g., pour-flush toilets, pit latrines), which serve an estimated 2.7 billion people globally, or fecal sludge management interventions on antibiotic resistance.Added value of this studyIn this study, we used 1589 publicly available human gut metagenomes from around the world to assess the abundance of ARGs as a function of access to improved drinking water and sanitation infrastructure. This analysis provides new evidence of differences in the abundance of antibiotic resistance in the human gut across the world and finds that decreased gut abundance of ARGs is associated with increased access to improved drinking water and sanitation.Implications of all the available evidenceCurrent approaches to controlling antibiotic resistance in humans predominantly focus on antibiotic stewardship; however, this approach is challenging in LMICs where infectious illnesses are generally more prevalent and unregulated antibiotic usage is common. Along with efforts to provide other known social benefits, such as reducing infectious disease and improving gender equality, improving access to safe drinking water and sanitation could contribute to reducing the burden of antibiotic resistance. This work highlights improving access to adequate water and sanitation as a potentially effective strategy, although additional studies designed to rigorously investigate the casual relationship between WASH and antibiotic resistance are needed.

HIGHLIGHTS • 89 surface disinfection efficacy studies were synthesized and data made available • Experimental procedures and disinfection efficacies exhibit dramatic variability • Target chlorine concentration-times were determined for 6 relevant pathogens • Improvements in consistency, reproducibility, and reporting are needed, Background Infectious diseases can be transmitted via fomites (contaminated surfaces/objects); disinfection can interrupt this transmission route. However, disinfection guidelines for low-resource outbreak settings are inconsistent and not evidence-based. Methods A systematic review of surface disinfection efficacy studies was conducted to inform low-resource outbreak guideline development. Due to variation in experimental procedures, outcomes were synthesized in a narrative summary focusing on chlorine-based disinfection against seven pathogens with potential to produce outbreaks in low-resource settings (Mycobacterium tuberculosis, Vibrio cholerae, Salmonella spp., hepatitis A virus, rotavirus, norovirus, Ebola virus). Results Data were extracted from 89 laboratory studies and made available, including 20 studies on relevant pathogens used in combination with surrogate data to determine minimum target concentration × time (“CT”) factors. Stainless steel (68%) and chlorine-based disinfectants (56%) were most commonly tested. No consistent trend was seen in the influence of chlorine concentration and exposure time on disinfection efficacy. Disinfectant application mode; soil load; and surface type were frequently identified as influential factors in included studies. Conclusions This review highlights that surface disinfection efficacy estimates are strongly influenced by each study's experimental conditions. We therefore recommend laboratory testing to be followed by field-based testing/monitoring to ensure effectiveness is achieved in situ.

Diarrhoeal disease remains a leading cause of mortality and morbidity worldwide. Cholera alone is estimated to cause 95,000 deaths per year, most of which occur in endemic settings with inadequate water access. Whilst a global strategy to eliminate cholera by 2030 calls for investment in improved drinking water services, there is limited rigorous evidence for the impact of improved water supply on endemic cholera transmission in low-income urban settings. Our protocol is designed to deliver a pragmatic health impact evaluation of a large-scale water supply intervention in Uvira (Democratic Republic of the Congo), a cholera transmission hotspot.A stepped-wedge cluster randomised trial (SW-CRT) was designed to evaluate the impact of a large-scale drinking water supply intervention on cholera incidence among the 280,000 inhabitants of Uvira. The city was divided into 16 clusters, where new community and household taps will be installed following a randomised sequence over a transition period of up to 8 weeks in each cluster. The primary trial outcomes are the monthly incidence of "confirmed" cholera cases (patients testing positive by rapid detection kit) and of "suspected" cholera cases (patients admitted to the cholera treatment centre). Concurrent process and economic evaluations will provide further information on the context, costs, and efficiency of the intervention.In this protocol, we describe a pragmatic approach to conducting rigorous research to assess the impacts of a complex water supply intervention on severe diarrhoeal disease and cholera in an unstable, low-resource setting representative of cholera-affected areas. In particular, we discuss a series of pre-identified risks and linked mitigation strategies as well as the value of combining different data collection methods and preparation of multiple analysis scenarios to account for possible deviations from the protocol. The study described here has the potential to provide robust evidence to support more effective cholera control in challenging, high-burden settings.This trial is registered on clinicaltrials.gov ( NCT02928341 , 10th October 2016) and has received ethics approval from the London School of Hygiene and Tropical Medicine (8913, 10603) and from the Ethics Committee from the School of Public Health, University of Kinshasa, Democratic Republic of the Congo (ESP/CE/088/2015).RESUME (VERSION FRANçAISE): Please note this translation has been generated by the authors and has not been checked against the original, peer-reviewed English version by the Journal. Any discrepancies between the two versions should be raised with the authors. Cette traduction a été préparée par les auteurs et sa conformité avec la version anglaise revue par les pairs n’a pas été vérifiée par le journal. Toute différence entre les deux versions doit être signalée aux auteurs. INTRODUCTION: Les maladies diarrhéiques restent une cause majeure de mortalité et morbidité dans le monde. Le choléra seul cause environ 95’000 morts par an, dont la plupart dans des contextes endémiques où l’accès à l’eau est inadéquat. Tandis qu’une stratégie globale pour l’élimination du choléra d’ici à 2030 appelle des investissements dans l’amélioration des services d’approvisionnement en eau, il y a peu de données probantes et rigoureuses sur l’impact d’un approvisionnement en eau amélioré sur la transmission endémique du choléra dans les contextes urbains à faibles ressources. Notre protocole d’étude est conçu pour livrer une évaluation d’impact épidémiologique pragmatique d’une intervention d’approvisionnement en eau à large échelle à Uvira, République Démocratique du Congo, un point focal de transmission du choléra. MéTHODES/CONCEPTION: Un essai randomisé par grappes par échelons (stepped-wedge cluster randomised trial, SW-CRT) a été conçu pour évaluer l’impact d’une intervention d’approvisionnement en eau potable à large échelle sur l’incidence du choléra parmi les 280'000 habitants d’Uvira. La ville a été divisée en 16 grappes, dans lesquelles de nouvelles bornes fontaines et branchements individuels seront installés suivant une séquence randomisée sur une période allant jusqu’à 8 semaines par grappe. Le principal résultat de l’essai sera l’incidence mensuelle des cas de choléra « confirmés » (patients positifs par tests de détection rapide) et des cas « suspects » (patients admis au centre de traitement du choléra). Des évaluations de processus et économique menées en parallèle fourniront des informations complémentaires sur le contexte, les coûts et l’efficience de l’intervention. DISCUSSION: Dans ce protocole, nous présentons une approche pragmatique pour effectuer une recherche rigoureuse visant à évaluer les impacts d’une intervention complexe d’approvisionnement en eau sur la diarrhée sévère et le choléra dans un contexte instable et à faibles ressources, représentatif des zones affectées par le choléra. En particulier, nous considérons une série de risques pré-identifiés et les stratégies de mitigation associées ainsi que la valeur de combiner différentes méthodes de collecte de données et de préparer de multiples scénarios d’analyse pour tenir compte d’éventuelles déviations du protocole. L’étude présentée ici a le potentiel de fournir des évidences scientifiques robustes pour soutenir des stratégies de contrôle du choléra plus efficientes dans les contextes difficiles qui sont fortement affectés. ENREGISTREMENT DE L’ESSAI: Cet essai est enregistré sur clinicaltrials.gov ( NCT02928341 , 10 octobre 2016) et a reçu les approbations éthiques de la London School of Hygiene and Tropical Medicine (8913, 10603) ainsi que de l’Ecole de Santé Publique de l’Université de Kinshasa, République Démocratique du Congo (ESP/CE/088/2015).

Background Provision of safe water, sanitation, and hygiene (WASH) to affected populations in humanitarian emergencies is necessary for dignity and communicable disease control. Additional evidence on WASH interventions is needed in humanitarian settings. Between 2008 and 2019, we completed six multi-country, mixed-methods effectiveness studies in humanitarian response on six different WASH interventions. In each evaluation, we conducted: key informant interviews; water point observations and water quality testing; household surveys with recipients, including survey and water quality testing; focus group discussions; and/or, secondary data analysis. The research questions were: “What is the effectiveness of [intervention] in reducing the risk of diarrhea/cholera transmission; and, what programmatic factors lead to higher effectiveness?” Discussion In all six multi-country, mixed-methods evaluations, policy-relevant outcomes were obtained. We found, in our individual research results, that: interventions could reduce the risk of disease in humanitarian contexts; this reduction of risk did not always occur, as there were large ranges in effectiveness; and, implementation factors were crucial to intervention effectiveness. When collaboratively reviewing our research process across evaluations, we found strategies for successfully conducting this research included: 1) working with partners to identify and evaluate programs; 2) rapidly obtaining approvals to deploy; and, 3) conducting research methodologies consistently. Personal connections, in-person communication, trust, and experience working together were key factors for success in identifying partners for evaluation. Successes in evaluation deployment occurred with flexibility, patience, commitment of adequate time, and understanding of processes; although we note access and security concerns in insecure contexts precluded deployment. Consistent and robust protocols, flexibility, and a consistent researcher on the ground in each context allowed for methodological consistency and high-quality results. Conclusions In conclusion, we have found multi-country, mixed-methods results to be one crucial piece of the WASH evidence base in humanitarian contexts. This is particularly because evaluations of reductions in risk from real-world programming are policy-relevant, and are directly used to improve programming. In future, we need to flexibly work with donors, agencies, institutions, responders, local governments, local responders, and beneficiaries to design safe and ethical research protocols to answer questions related to WASH interventions effectiveness in humanitarian response, and, improve WASH programming.

Before the coronavirus 2019 (COVID-19) pandemic began, antimicrobial resistance (AMR) was among the top priorities for global public health. Already a complex challenge, AMR now needs to be addressed in a changing healthcare landscape. Here, we analyse how changes due to COVID-19 in terms of antimicrobial usage, infection prevention, and health systems affect the emergence, transmission, and burden of AMR. Increased hand hygiene, decreased international travel, and decreased elective hospital procedures may reduce AMR pathogen selection and spread in the short term. However, the opposite effects may be seen if antibiotics are more widely used as standard healthcare pathways break down. Over 6 months into the COVID-19 pandemic, the dynamics of AMR remain uncertain. We call for the AMR community to keep a global perspective while designing finely tuned surveillance and research to continue to improve our preparedness and response to these intersecting public health challenges.

IntroductionCholera remains a frequent cause of outbreaks globally, particularly in areas with inadequate water, sanitation and hygiene (WASH) services. Cholera is spread through faecal-oral routes, and studies demonstrate that ingestion of Vibrio cholerae occurs from consuming contaminated food and water, contact with cholera cases and transmission from contaminated environmental point sources. WASH guidelines recommending interventions for the prevention and control of cholera are numerous and vary considerably in their recommendations. To date, there has been no review of practice guidelines used in cholera prevention and control programmes.MethodsWe systematically searched international agency websites to identify WASH intervention guidelines used in cholera programmes in endemic and epidemic settings. Recommendations listed in the guidelines were extracted, categorised and analysed. Analysis was based on consistency, concordance and recommendations were classified on the basis of whether the interventions targeted within-household or community-level transmission.ResultsEight international guidelines were included in this review: three by non-governmental organisations (NGOs), one from a non-profit organisation (NPO), three from multilateral organisations and one from a research institution. There were 95 distinct recommendations identified, and concordance among guidelines was poor to fair. All categories of WASH interventions were featured in the guidelines. The majority of recommendations targeted community-level transmission (45%), 35% targeted within-household transmission and 20% both.ConclusionsRecent evidence suggests that interventions for effective cholera control and response to epidemics should focus on case-centred approaches and within-household transmission. Guidelines did consistently propose interventions targeting transmission within households. However, the majority of recommendations listed in guidelines targeted community-level transmission and tended to be more focused on preventing contamination of the environment by cases or recurrent outbreaks, and the level of service required to interrupt community-level transmission was often not specified. The guidelines in current use were varied and interpretation may be difficult when conflicting recommendations are provided. Future editions of guidelines should reflect on the inclusion of evidence-based approaches, cholera transmission models and resource-efficient strategies.

There are increasing numbers of people affected by natural disasters, disease outbreaks, and conflict. Water, sanitation, and hygiene (WASH) interventions are used in nearly all emergency responses to help reduce disease risk. However, there is a lack of summarized evidence on the efficacy and effectiveness of these interventions. We conducted a systematic review of the published and grey literature on the efficacy and effectiveness of short-term WASH interventions in emergency response in low- and middle-income countries, including: developing theory of change models; setting inclusion criteria; conducting the search; selecting evaluations for inclusion; assessing the quality of the evidence; and analysing the included evaluations. Overall, 15,026 documents were identified and 106 studies describing 114 evaluations met inclusion criteria. Interventions from 39 countries were included. Most included evaluations (77 per cent) had high risk of bias and half were from grey literature (50 per cent). For the m...

Chlorine tablets are commonly distributed for household water treatment in emergencies. However, confirmed use after distribution ranges widely (from 7&ndash, 87%), which raises concerns about chlorine tablet effectiveness, as measured by acceptance and appropriate use. To investigate chlorine tablet effectiveness, we conducted nine key informant interviews (KIIs) on tablet distribution in emergencies in general, five KIIs on chlorine taste and odor acceptance and rejection specifically, and a literature review on chlorine taste and odor concerns. We found: (1) chlorine tablets are regarded as one of the most effective water treatment methods and are often considered appropriate in emergency response, (2) dosing confusion and taste and odor rejection are perceived as the main problems limiting effectiveness, and (3) the primary solutions suggested for these problems were social and behavioral. We recommend that social and behavioral scientists are routinely integrated into chlorine tablet programming to improve user feedback and behavioral interventions for chlorine tablet promotion in emergencies. We also suggest that more research is conducted on chlorine taste and odor rejection in vulnerable populations, and that improved guidance is developed to facilitate intra-agency coordination and select, promote, and monitor tablets appropriate for each context.

In the 2014 West African Ebola outbreak, international organizations provided conflicting recommendations for disinfecting surfaces contaminated by uncontrolled patient spills. We compared the efficacy of four chlorine solutions (sodium hypochlorite, sodium dichloroisocyanurate, high-test hypochlorite, and generated hypochlorite) for disinfection of three surface types (stainless steel, heavy-duty tarp, and nitrile) with and without pre-cleaning practices (prewiping, covering, or both) and soil load. The test organisms were Escherichia coli and the Ebola surrogate Phi6. All tests achieved a minimum of 5.9 and 3.1 log removal in E. coli and Phi6, respectively. A 15 min exposure to 0.5% chlorine was sufficient to ensure

The 2014 West African Ebola virus disease outbreak was the largest to date, and conflicting, chlorine-based surface disinfection protocols to interrupt disease transmission were recommended. We identified only one study documenting surface disinfection efficacy against the Ebola virus, showing a >6.6 log reduction after 5-minute exposure to 0.5% sodium hypochlorite (NaOCl) based on small-scale tests (Cook et al. (2015)). In preparation for future extensive, large-scale disinfection efficacy experiments, we replicated the Cook et al. experiment using four potential BSL-1 surrogates selected based on similarities to the Ebola virus: bacteriophages MS2, M13, Phi6, and PR772. Each bacteriophage was exposed to 0.1% and 0.5% NaOCl for 1, 5, and 10 minutes on stainless steel. MS2 and M13 were only reduced by 3.4 log and 3.5 log after a 10-minute exposure to 0.5% NaOCl, and would be overly conservative surrogates. Conversely, PR772 was too easily inactivated for surrogate use, as it was reduced by >4.8 log after only 1-minute exposure to 0.5% NaOCl. Phi6 was slightly more resistant than the Ebola virus, with 4.1 log reduction after a 5-minute exposure and not detected after a 10-minute exposure to 0.5% NaOCl. We therefore recommend Phi6 as a surrogate for evaluating the efficacy of chlorine-based surface disinfectants against the Ebola virus.

Sodium hypochlorite (NaOCl) and sodium dichloroisocyanurate (NaDCC) are commonly used for household water treatment (HWT), chlorine dioxide (ClO2) is a potential new HWT option. We compared the residual maintenance of NaOCl, NaDCC, and ClO2 over 24 hours using recommended dosages (2 and 4 mg/L) in waters of varying turbidity (0&ndash, 300 NTU, from kaolin clay or creek-bottom sediments) and total organic carbon (TOC) concentrations (0&ndash, 100 mg/L), for a total of 324 reactors. NaOCl and NaDCC had similar free chlorine decay rates, and ClO2 decayed more rapidly across all of the tested conditions. Little variability was observed across clay-based turbidity levels and TOC concentrations. With a dosage of 2 mg/L, a residual &ge, 0.2 mg/L was maintained at 30 NTU for NaOCl and 100 NTU for NaDCC, for ClO2, 4 mg/L were required to maintain &ge, 0.2 mg/L under all conditions except at zero turbidity. Comparisons with data from the literature suggest that the three compounds would inactivate E. coli, rotavirus, and Giardia cysts within 1 hour under all conditions, except 300 NTU for NaOCl and NaDCC. All three disinfectants are similarly efficacious for this usage, however, differences are seen in decay rates that may influence disinfectant selection depending on water storage time.