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1.
Nat Commun ; 15(1): 1556, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378704

RESUMO

Many diarrhea-causing pathogens are climate-sensitive, and populations with the lowest socioeconomic position (SEP) are often most vulnerable to climate-related transmission. Household Water, Sanitation, and Handwashing (WASH) interventions constitute one potential effective strategy to reduce child diarrhea, especially among low-income households. Capitalizing on a cluster randomized trial population (360 clusters, 4941 children with 8440 measurements) in rural Bangladesh, one of the world's most climate-sensitive regions, we show that improved WASH substantially reduces diarrhea risk with largest benefits among children with lowest SEP and during the monsoon season. We extrapolated trial results to rural Bangladesh regions using high-resolution geospatial layers to identify areas most likely to benefit. Scaling up a similar intervention could prevent an estimated 734 (95% CI 385, 1085) cases per 1000 children per month during the seasonal monsoon, with marked regional heterogeneities. Here, we show how to extend large-scale trials to inform WASH strategies among climate-sensitive and low-income populations.


Assuntos
Higiene , Saneamento , Criança , Humanos , Desinfecção das Mãos , Bangladesh/epidemiologia , Água , Diarreia/epidemiologia , Diarreia/prevenção & controle , População Rural , Fatores Socioeconômicos
2.
Nature ; 621(7979): 568-576, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37704722

RESUMO

Growth faltering in children (low length for age or low weight for length) during the first 1,000 days of life (from conception to 2 years of age) influences short-term and long-term health and survival1,2. Interventions such as nutritional supplementation during pregnancy and the postnatal period could help prevent growth faltering, but programmatic action has been insufficient to eliminate the high burden of stunting and wasting in low- and middle-income countries. Identification of age windows and population subgroups on which to focus will benefit future preventive efforts. Here we use a population intervention effects analysis of 33 longitudinal cohorts (83,671 children, 662,763 measurements) and 30 separate exposures to show that improving maternal anthropometry and child condition at birth accounted for population increases in length-for-age z-scores of up to 0.40 and weight-for-length z-scores of up to 0.15 by 24 months of age. Boys had consistently higher risk of all forms of growth faltering than girls. Early postnatal growth faltering predisposed children to subsequent and persistent growth faltering. Children with multiple growth deficits exhibited higher mortality rates from birth to 2 years of age than children without growth deficits (hazard ratios 1.9 to 8.7). The importance of prenatal causes and severe consequences for children who experienced early growth faltering support a focus on pre-conception and pregnancy as a key opportunity for new preventive interventions.


Assuntos
Caquexia , Países em Desenvolvimento , Transtornos do Crescimento , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Caquexia/economia , Caquexia/epidemiologia , Caquexia/etiologia , Caquexia/prevenção & controle , Estudos de Coortes , Países em Desenvolvimento/economia , Países em Desenvolvimento/estatística & dados numéricos , Suplementos Nutricionais , Transtornos do Crescimento/epidemiologia , Transtornos do Crescimento/prevenção & controle , Estudos Longitudinais , Mães , Fatores Sexuais , Desnutrição/economia , Desnutrição/epidemiologia , Desnutrição/etiologia , Desnutrição/prevenção & controle , Antropometria
3.
Lancet ; 401(10393): 2060-2071, 2023 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-37290458

RESUMO

BACKGROUND: Assessments of disease burden are important to inform national, regional, and global strategies and to guide investment. We aimed to estimate the drinking water, sanitation, and hygiene (WASH)-attributable burden of disease for diarrhoea, acute respiratory infections, undernutrition, and soil-transmitted helminthiasis, using the WASH service levels used to monitor the UN Sustainable Development Goals (SDGs) as counterfactual minimum risk-exposure levels. METHODS: We assessed the WASH-attributable disease burden of the four health outcomes overall and disaggregated by region, age, and sex for the year 2019. We calculated WASH-attributable fractions of diarrhoea and acute respiratory infections by country using modelled WASH exposures and exposure-response relationships from two updated meta-analyses. We used the WHO and UNICEF Joint Monitoring Programme for Water Supply, Sanitation and Hygiene public database to estimate population exposure to different WASH service levels. WASH-attributable undernutrition was estimated by combining the population attributable fractions (PAF) of diarrhoea caused by unsafe WASH and the PAF of undernutrition caused by diarrhoea. Soil-transmitted helminthiasis was fully attributed to unsafe WASH. FINDINGS: We estimate that 1·4 (95% CI 1·3-1·5) million deaths and 74 (68-80) million disability-adjusted life-years (DALYs) could have been prevented by safe WASH in 2019 across the four designated outcomes, representing 2·5% of global deaths and 2·9% of global DALYs from all causes. The proportion of diarrhoea that is attributable to unsafe WASH is 0·69 (0·65-0·72), 0·14 (0·13-0·17) for acute respiratory infections, and 0·10 (0·09-0·10) for undernutrition, and we assume that the entire disease burden from soil-transmitted helminthiasis was attributable to unsafe WASH. INTERPRETATION: WASH-attributable burden of disease estimates based on the levels of service established under the SDG framework show that progress towards the internationally agreed goal of safely managed WASH services for all would yield major public-health returns. FUNDING: WHO and Foreign, Commonwealth & Development Office.


Assuntos
Água Potável , Helmintíase , Desnutrição , Infecções Respiratórias , Humanos , Saneamento , Higiene , Helmintíase/epidemiologia , Desnutrição/epidemiologia , Efeitos Psicossociais da Doença , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/etiologia , Diarreia/epidemiologia , Diarreia/etiologia , Avaliação de Resultados em Cuidados de Saúde , Saúde Global , Carga Global da Doença
4.
Vaccine ; 41(23): 3493-3496, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37150621

RESUMO

Recombinant zoster vaccine (RZV) is recommended for individuals ≥ 50 years of age for protection against herpes zoster (HZ). This study quantifies RZV coverage and assesses predictors for RZV vaccination using a U.S. claims database. Univariate linear regression provided annual prevalence of RZV vaccination and multivariable logistic regression provided ORs and 95% CIs for associations between predictors and RZV vaccination. A total of 4,124,315 individuals (19,080,914 person-years) were included in this study. Since receiving FDA approval for the prevention of HZ, RZV coverage (of at least one dose) has reached approximately 17% within the eligible U.S. population by January 2021, although significant disparities between demographic groups were noted. Our findings suggest that HZ vaccine coverage may be reduced below goal in the U.S. and highlights the importance of continuing to monitor RZV vaccination. Additionally, as our study found disparities in vaccine coverage, attention towards marginalized and medically underserved populations is needed.


Assuntos
Vacina contra Herpes Zoster , Herpes Zoster , Humanos , Estados Unidos , Análise Custo-Benefício , Herpes Zoster/epidemiologia , Herpes Zoster/prevenção & controle , Vacinas Sintéticas , Herpesvirus Humano 3
5.
JAMA Netw Open ; 5(11): e2242240, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36383382

RESUMO

Importance: Herpes zoster infection after COVID-19 vaccination has been reported in numerous case studies. It is not known whether these cases represent increased reporting or a true increase in risk. Objective: To assess whether COVID-19 vaccination is associated with an increased risk of herpes zoster infection. Design, Setting, and Participants: This cohort study used a self-controlled risk interval (SCRI) design to compare the risk of herpes zoster in a risk interval of 30 days after COVID-19 vaccination or up to the date of the second vaccine dose with a control interval remote from COVID-19 vaccination (defined as 60-90 days after the last recorded vaccination date for each individual, allowing for a 30-day washout period between control and risk intervals). A supplemental cohort analysis was used to compare the risk of herpes zoster after COVID-19 vaccination with the risk of herpes zoster after influenza vaccination among 2 historical cohorts who received an influenza vaccine in the prepandemic period (January 1, 2018, to December 31, 2019) or the early pandemic period (March 1, 2020, to November 30, 2020). Data were obtained from Optum Labs Data Warehouse, a US national deidentified claims-based database. A total of 2 039 854 individuals who received any dose of a COVID-19 vaccine with emergency use authorization (BNT162b2 [Pfizer-BioNTech], mRNA-1273 [Moderna], or Ad26.COV2.S [Johnson & Johnson]) from December 11, 2020, through June 30, 2021, were eligible for inclusion. Individuals included in the SCRI analysis were a subset of the COVID-19-vaccinated cohort who had herpes zoster during either a risk or control interval. Exposures: Any dose of a COVID-19 vaccine. Main Outcomes and Measures: Incident herpes zoster, defined by International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes and a prescription of a new antiviral medication or a dose increase in antiviral medication within 5 days of diagnosis. Results: Among 2 039 854 individuals who received any dose of a COVID-19 vaccine during the study period, the mean (SD) age was 43.2 (16.3) years; 1 031 149 individuals (50.6%) were female, and 1 344 318 (65.9%) were White. Of those, 1451 patients (mean [SD] age, 51.6 [12.6] years; 845 [58.2%] female) with a herpes zoster diagnosis were included in the primary SCRI analysis. In the SCRI analysis, COVID-19 vaccination was not associated with an increased risk of herpes zoster after adjustment (incidence rate ratio, 0.91; 95% CI, 0.82-1.01; P = .08). In the supplementary cohort analysis, COVID-19 vaccination was not associated with a higher risk of herpes zoster compared with influenza vaccination in the prepandemic period (first dose of COVID-19 vaccine: hazard ratio [HR], 0.78 [95% CI, 0.70-0.86; P < .001]; second dose of COVID-19 vaccine: HR, 0.79 [95% CI, 0.71-0.88; P < .001]) or the early pandemic period (first dose of COVID-19 vaccine: HR, 0.89 [95% CI, 0.80-1.00; P = .05]; second dose: HR, 0.91 [95% CI, 0.81-1.02; P = .09]). Conclusions and Relevance: In this study, there was no association found between COVID-19 vaccination and an increased risk of herpes zoster infection, which may help to address concerns about the safety profile of the COVID-19 vaccines among patients and clinicians.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Herpes Zoster , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ad26COVS1 , Antivirais/uso terapêutico , Vacina BNT162 , Estudos de Coortes , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Herpes Zoster/epidemiologia , Herpes Zoster/prevenção & controle , Herpes Zoster/tratamento farmacológico , Vacina contra Herpes Zoster/efeitos adversos , Influenza Humana/tratamento farmacológico
6.
Ophthalmology ; 129(3): 334-343, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34648828

RESUMO

PURPOSE: To identify if noninfectious uveitis (NIU) is associated with a greater risk of Coronavirus Disease 2019 (COVID-19) infection, hospitalization, and death. DESIGN: A retrospective cohort study from January 20, 2020 to December 31, 2020, using a national claims-based database. PARTICIPANTS: Enrollees who had continuous enrollment with both medical and pharmacy coverage for 3 years before January 20, 2020. Patients with an NIU diagnosis within 3 years of the start of the study were included in the NIU cohort. Those with infectious uveitis codes or new NIU diagnoses during the risk period were excluded. METHODS: Cox proportional hazard models were used to identify unadjusted hazard ratios (HRs) and adjusted HRs for all covariates for each outcome measure. Adjusted models accounted for patient demographics, health status, and immunosuppressive medication use during the risk period. MAIN OUTCOME MEASURES: Rates of COVID-19 infection, COVID-19-related hospitalization, and COVID-19-related in-hospital death identified with International Classification of Disease 10th revision codes. RESULTS: This study included 5 806 227 patients, of whom 29 869 (0.5%) had a diagnosis of NIU. On unadjusted analysis, patients with NIU had a higher rate of COVID-19 infection (5.7% vs. 4.5%, P < 0.001), COVID-19-related hospitalization (1.2% vs. 0.6%, P < 0.001), and COVID-19-related death (0.3% vs. 0.1%, P < 0.001). However, in adjusted models, NIU was not associated with a greater risk of COVID-19 infection (HR, 1.05; 95% confidence interval [CI], 1.00-1.10; P = 0.04), hospitalization (HR, 0.98; 95% CI, 0.88-1.09; P = 0.67), or death (HR, 0.90, 95% CI, 0.72-1.13, P = 0.37). Use of systemic corticosteroids was significantly associated with a higher risk of COVID-19 infection, hospitalization, and death. CONCLUSIONS: Patients with NIU were significantly more likely to be infected with COVID-19 and experience severe disease outcomes. However, this association was due to the demographics, comorbidities, and medications of patients with NIU, rather than NIU alone. Patients using systemic corticosteroids were significantly more likely to be infected with COVID-19 and were at greater risk of hospitalization and in-hospital death. Additional investigation is necessary to identify the impact of corticosteroid exposure on COVID-19-related outcomes.


Assuntos
COVID-19/epidemiologia , Mortalidade Hospitalar , Hospitalização/estatística & dados numéricos , Revisão da Utilização de Seguros/estatística & dados numéricos , SARS-CoV-2 , Uveíte/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Estados Unidos/epidemiologia , Uveíte/diagnóstico , Uveíte/tratamento farmacológico
7.
Am J Clin Nutr ; 114(Suppl 1): 43S-67S, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34590116

RESUMO

BACKGROUND: Small-quantity (SQ) lipid-based nutrient supplements (LNSs) provide many nutrients needed for brain development. OBJECTIVES: We aimed to generate pooled estimates of the effect of SQ-LNSs on developmental outcomes (language, social-emotional, motor, and executive function), and to identify study-level and individual-level modifiers of these effects. METHODS: We conducted a 2-stage meta-analysis of individual participant data from 14 intervention against control group comparisons in 13 randomized trials of SQ-LNSs provided to children age 6-24 mo (total n = 30,024). RESULTS: In 11-13 intervention against control group comparisons (n = 23,588-24,561), SQ-LNSs increased mean language (mean difference: 0.07 SD; 95% CI: 0.04, 0.10 SD), social-emotional (0.08; 0.05, 0.11 SD), and motor scores (0.08; 95% CI: 0.05, 0.11 SD) and reduced the prevalence of children in the lowest decile of these scores by 16% (prevalence ratio: 0.84; 95% CI: 0.76, 0.92), 19% (0.81; 95% CI: 0.74, 0.89), and 16% (0.84; 95% CI: 0.76, 0.92), respectively. SQ-LNSs also increased the prevalence of children walking without support at 12 mo by 9% (1.09; 95% CI: 1.05, 1.14). Effects of SQ-LNSs on language, social-emotional, and motor outcomes were larger among study populations with a higher stunting burden (≥35%) (mean difference: 0.11-0.13 SD; 8-9 comparisons). At the individual level, greater effects of SQ-LNSs were found on language among children who were acutely malnourished (mean difference: 0.31) at baseline; on language (0.12), motor (0.11), and executive function (0.06) among children in households with lower socioeconomic status; and on motor development among later-born children (0.11), children of older mothers (0.10), and children of mothers with lower education (0.11). CONCLUSIONS: Child SQ-LNSs can be expected to result in modest developmental gains, which would be analogous to 1-1.5 IQ points on an IQ test, particularly in populations with a high child stunting burden. Certain groups of children who experience higher-risk environments have greater potential to benefit from SQ-LNSs in developmental outcomes.This trial was registered at www.crd.york.ac.uk/PROSPERO as CRD42020159971.


Assuntos
Desenvolvimento Infantil/efeitos dos fármacos , Suplementos Nutricionais , Fenômenos Fisiológicos da Nutrição do Lactente , Lipídeos/administração & dosagem , África Subsaariana/epidemiologia , Bangladesh/epidemiologia , Pré-Escolar , Modificador do Efeito Epidemiológico , Feminino , Haiti/epidemiologia , Humanos , Lactente , Desenvolvimento da Linguagem , Masculino , Destreza Motora , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores Socioeconômicos
8.
Ophthalmology ; 128(12): 1699-1707, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33892049

RESUMO

PURPOSE: To examine the effectiveness of the recombinant zoster vaccine (RZV) for preventing herpes zoster ophthalmicus (HZO) in the general United States population. DESIGN: Retrospective, observational cohort study. PARTICIPANTS: Individuals enrolled in the OptumLabs Data Warehouse (OLDW; OptumLabs, Cambridge, MA) who were age eligible for herpes zoster (HZ) vaccination (≥50 years of age) from 2018 through 2019. The OLDW is a longitudinal, de-identified administrative claims and electronic health record database of patients in the United States with commercial insurance, Medicare Part D, or Medicare Advantage METHODS: Patients were required to have 365 days or more of continuous enrollment to be eligible. Those with a diagnosis code of HZ or an immunocompromising condition within 1 year before study inclusion were excluded. Vaccination with the RZV was ascertained by Current Procedural Terminology codes, and HZO was ascertained by International Classification of Diseases, Tenth Revision, codes. Cox proportional hazards regression models were used to estimate the hazard ratio of HZO associated with RZV, and inverse-probability weighting was used to control for confounding. Vaccine effectiveness was calculated from hazard ratios. MAIN OUTCOME MEASURES: Incidence of HZO in vaccinated versus unvaccinated person-times and vaccine effectiveness were assessed. RESULTS: From January 1, 2018, through December 31, 2019, a total of 4 842 579 individuals were included in this study. One hundred seventy-seven thousand two hundred eighty-nine (3.7%) received 2 valid doses of RZV. The incidence rate of HZO was 25.5 cases (95% confidence interval [CI], 17.4-35.8 cases) per 100 000 person-years in the vaccinated group compared with 76.7 cases (95% CI, 74.7-78.7 cases) in the unvaccinated group. The overall adjusted effectiveness of RZV against HZO was 89.1% (95% CI, 82.9%-93.0%). CONCLUSIONS: The effectiveness of RZV against HZO in individuals 50 years of age and older is high in a clinical setting. However, the low vaccination rate in this study highlights the public health need to increase HZV use. Ophthalmologists can play an important role in recommending vaccination to eligible patients.


Assuntos
Herpes Zoster Oftálmico/prevenção & controle , Vacina contra Herpes Zoster/administração & dosagem , Eficácia de Vacinas/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Current Procedural Terminology , Bases de Dados Factuais/estatística & dados numéricos , Registros Eletrônicos de Saúde/estatística & dados numéricos , Feminino , Seguimentos , Herpes Zoster Oftálmico/epidemiologia , Humanos , Incidência , Masculino , Medicare Part D/estatística & dados numéricos , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Estados Unidos/epidemiologia , Vacinação , Vacinas Sintéticas
9.
Int J Epidemiol ; 46(4): 1251-1276, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28449030

RESUMO

Background: Many interventions delivered to improve health may benefit not only direct recipients but also people in close physical or social proximity. Our objective was to review all published literature about the spillover effects of interventions on health outcomes in low-middle income countries and to identify methods used in estimating these effects. Methods: We searched 19 electronic databases for articles published before 2014 and hand-searched titles from 2010 to 2013 in five relevant journals. We adapted the Cochrane Collaboration's quality grading tool for spillover estimation and rated the quality of evidence. Results: A total of 54 studies met inclusion criteria. We found a wide range of terminology used to describe spillovers, a lack of standardization among spillover methods and poor reporting of spillovers in many studies. We identified three primary mechanisms of spillovers: reduced disease transmission, social proximity and substitution of resources within households. We found the strongest evidence for spillovers through reduced disease transmission, particularly vaccines and mass drug administration. In general, the proportion of a population receiving an intervention was associated with improved health. Most studies were of moderate or low quality. We found evidence of publication bias for certain spillover estimates but not for total or direct effects. To facilitate improved reporting and standardization in future studies, we developed a reporting checklist adapted from the CONSORT framework specific to reporting spillover effects. Conclusions: We found the strongest evidence for spillovers from vaccines and mass drug administration to control infectious disease. There was little high quality evidence of spillovers for other interventions.


Assuntos
Promoção da Saúde/métodos , Apoio Social , Países em Desenvolvimento , Transmissão de Doença Infecciosa/prevenção & controle , Humanos , Fatores Socioeconômicos , Vacinação
10.
Environ Health Perspect ; 125(3): 278-283, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27634098

RESUMO

BACKGROUND: The recent global climate agreement in Paris aims to mitigate greenhouse gas emissions while fostering sustainable development and establishes an international trading mechanism to meet this goal. Currently, carbon offset program implementers are allowed to collect their own monitoring data to determine the number of carbon credits to be awarded. OBJECTIVES: We summarize reasons for mandating independent monitoring of greenhouse gas emission reduction projects. In support of our policy recommendations, we describe a case study of a program designed to earn carbon credits by distributing almost one million drinking water filters in rural Kenya to avert the use of fuel for boiling water. We compare results from an assessment conducted by our research team in the program area among households with pregnant women or caregivers in rural villages with low piped water access with the reported program monitoring data and discuss the implications. DISCUSSION: Our assessment in Kenya found lower levels of household water filter usage than the internal program monitoring reported estimates used to determine carbon credits; we found 19% (n = 4,041) of households reported filter usage 2-3 years after filter distribution compared to the program stated usage rate of 81% (n = 14,988) 2.7 years after filter distribution. Although carbon financing could be a financially sustainable approach to scale up water treatment and improve health in low-income settings, these results suggest program effectiveness will remain uncertain in the absence of requiring monitoring data be collected by third-party organizations. CONCLUSION: Independent monitoring should be a key requirement for carbon credit verification in future international carbon trading mechanisms to ensure programs achieve benefits in line with sustainable development goals. Citation: Pickering AJ, Arnold BF, Dentz HN, Colford JM Jr., Null C. 2017. Climate and health co-benefits in low-income countries: a case study of carbon financed water filters in Kenya and a call for independent monitoring. Environ Health Perspect 125:278-283; http://dx.doi.org/10.1289/EHP342.


Assuntos
Países em Desenvolvimento/estatística & dados numéricos , Monitoramento Ambiental , Purificação da Água/métodos , Carbono , Clima , Conservação dos Recursos Naturais , Água Potável , Filtração/economia , Filtração/instrumentação , Humanos , Quênia , Pobreza
11.
Water Res ; 94: 371-381, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27040577

RESUMO

INTRODUCTION: Advances in molecular methods provide new opportunities for directly measuring pathogens or host-associated markers of fecal pollution instead of relying on fecal indicator bacteria (FIB) alone for beach water quality monitoring. Adoption of new indicators depends on identifying relationships between either the presence or concentration of the indicators and illness among swimmers. Here we present results from three epidemiologic studies in which a broad range of bacterial and viral indicators of fecal contamination were measured simultaneously by either culture or molecular methods along with Enterococcus to assess whether they provide better health risk prediction than current microbial indicators of recreational water quality. METHODS: We conducted prospective cohort studies at three California beaches -- Avalon Bay (Avalon), Doheny State Beach (Doheny), Surfrider State Beach (Malibu) -- during the summers of 2007, 2008 and 2009. The studies enrolled 10,785 swimmers across the beaches and recorded each swimmer's water exposure. Water and sand samples were collected several times per day at multiple locations at each beach and analyzed for up to 41 target indicators using 67 different methodologies. Interviewers contacted participants by phone 10-14 days later and recorded symptoms of gastrointestinal illness occurring after their beach visit. Regression models were used to evaluate the association between water quality indicators and gastrointestinal illness among swimmers at each beach. RESULTS: F+ coliphage (measured using EPA Method 1602) exhibited a stronger association with GI illness than did EPA Method 1600 at the two beaches where it was measured, while a molecular method, F+ RNA Coliphage Genotype II, was the only indicator significantly associated with GI illness at Malibu. MRSA, a known pathogen, had the strongest association with GI illness of any microbe measured at Avalon. There were two methods targeting human-associated fecal anaerobic bacteria that were more strongly associated with GI illness than EPA Method 1600, but only at Avalon. No indicator combinations consistently had a higher odds ratio than EPA Method 1600, but one composite indicator, based on the number of pathogens detected at a beach, was significantly associated with gastrointestinal illness at both Avalon and Doheny when freshwater flow was high. DISCUSSION: While EPA Method1600 performed adequately at two beaches based on its consistency of association with gastrointestinal illness and the precision of its estimated associations, F+ coliphage measured by EPA Method 1602 had a stronger association with GI illness under high risk conditions at the two beaches where it was measured. One indicator, F+ Coliphage Genotype II was the only indicator significantly associated with GI illness at Malibu. Several indicators, particularly those targeting human associated bacteria, exhibited relationships with GI illness that were equal to or greater than that of EPA Method 1600 at Avalon, which has a focused human fecal source. Our results suggest that site-specific conditions at each beach determine which indicator or indicators best predict GI illness.


Assuntos
Praias/normas , Monitoramento Ambiental/métodos , Microbiologia da Água , Poluição da Água/análise , Qualidade da Água/normas , California/epidemiologia , Colífagos/classificação , Colífagos/isolamento & purificação , Enterococcus/isolamento & purificação , Estudos Epidemiológicos , Fezes/microbiologia , Água Doce/microbiologia , Gastroenteropatias/epidemiologia , Gastroenteropatias/microbiologia , Gastroenteropatias/virologia , Humanos , Razão de Chances , Estudos Prospectivos , Água do Mar/microbiologia
12.
PLoS One ; 10(10): e0140997, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26495983

RESUMO

The cost and complexity of traditional methods for the detection of faecal indicator bacteria, including E. coli, hinder widespread monitoring of drinking water quality, especially in low-income countries and outside controlled laboratory settings. In these settings the problem is exacerbated by the lack of inexpensive media for the detection of E. coli in drinking water. We developed a new low-cost growth medium, aquatest (AT), and validated its use for the direct detection of E. coli in temperate and sub-tropical drinking waters using IDEXX Quanti-Tray®. AT was compared with IDEXX Colilert-18® and either EC-MUG or MLSB for detecting low levels of E. coli from water samples from temperate (n = 140; Bristol, UK) and subtropical regions (n = 50, Pretoria/Tshwane, South Africa). Confirmatory testing (n = 418 and 588, respectively) and the comparison of quantitative results were used to assess performance. Sensitivity of AT was higher than Colilert-18® for water samples in the UK [98.0% vs. 86.9%; p<0.0001] and South Africa [99.5% vs. 93.2%; p = 0.0030]. There was no significant difference in specificity, which was high for both media (>95% in both settings). Quantitative results were comparable and within expected limits. AT is reliable and accurate for the detection of E. coli in temperate and subtropical drinking water. The composition of the new medium is reported herein and can be used freely.


Assuntos
Água Potável/microbiologia , Monitoramento Ambiental/métodos , Escherichia coli/isolamento & purificação , Microbiologia da Água , Meios de Cultura/química , Meios de Cultura/economia , Monitoramento Ambiental/economia , Monitoramento Ambiental/instrumentação , Escherichia coli/crescimento & desenvolvimento , Humanos , Sensibilidade e Especificidade , África do Sul , Reino Unido , Qualidade da Água
13.
Am J Epidemiol ; 179(9): 1134-42, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24705812

RESUMO

Complier average causal effects (CACE) estimate the impact of an intervention among treatment compliers in randomized trials. Methods used to estimate CACE have been outlined for parallel-arm trials (e.g., using an instrumental variables (IV) estimator) but not for other randomized study designs. Here, we propose a method for estimating CACE in randomized stepped wedge trials, where experimental units cross over from control conditions to intervention conditions in a randomized sequence. We illustrate the approach with a cluster-randomized drinking water trial conducted in rural Mexico from 2009 to 2011. Additionally, we evaluated the plausibility of assumptions required to estimate CACE using the IV approach, which are testable in stepped wedge trials but not in parallel-arm trials. We observed small increases in the magnitude of CACE risk differences compared with intention-to-treat estimates for drinking water contamination (risk difference (RD) = -22% (95% confidence interval (CI): -33, -11) vs. RD = -19% (95% CI: -26, -12)) and diarrhea (RD = -0.8% (95% CI: -2.1, 0.4) vs. RD = -0.1% (95% CI: -1.1, 0.9)). Assumptions required for IV analysis were probably violated. Stepped wedge trials allow investigators to estimate CACE with an approach that avoids the stronger assumptions required for CACE estimation in parallel-arm trials. Inclusion of CACE estimates in stepped wedge trials with imperfect compliance could enhance reporting and interpretation of the results of such trials.


Assuntos
Causalidade , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Resultado do Tratamento , Adolescente , Adulto , Estudos Cross-Over , Diarreia/etiologia , Água Potável/efeitos adversos , Água Potável/microbiologia , Feminino , Humanos , Masculino , Saneamento , Fatores Socioeconômicos , Purificação da Água/métodos , Purificação da Água/normas , Qualidade da Água
14.
Am J Trop Med Hyg ; 89(2): 251-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23716404

RESUMO

In this large-scale longitudinal study conducted in rural Southern India, we compared a presence/absence hydrogen sulfide (H2S) test with quantitative assays for total coliforms and Escherichia coli as measures of water quality, health risk, and water supply vulnerability to microbial contamination. None of the three indicators showed a significant association with child diarrhea. The presence of H2S in a water sample was associated with higher levels of total coliform species that may have included E. coli but that were not restricted to E. coli. In addition, we observed a strong relationship between the percent positive H2S test results and total coliform levels among water source samples (R(2) = 0.87). The consistent relationships between H2S and total coliform levels indicate that presence/absence of H2S tests provide a cost-effective option for assessing both the vulnerability of water supplies to microbial contamination and the results of water quality management and risk mitigation efforts.


Assuntos
Diarreia/epidemiologia , Enterobacteriaceae/fisiologia , Sulfeto de Hidrogênio/química , Microbiologia da Água/normas , Abastecimento de Água/normas , Água/química , Pré-Escolar , Estudos de Coortes , Diarreia/etiologia , Feminino , Humanos , Índia/epidemiologia , Lactente , Masculino , Prevalência , Fatores de Risco , População Rural , Fatores Socioeconômicos
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