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OBJECTIVE: The effects of sanitation and hygiene interventions on the gut microbiome and enteric pathogen burden are not well understood. We measured the association between free chlorine residue (FCR) levels in drinking water, microbiome composition, and stool enteric pathogens in infants and young children in Haiti. METHODS: FCR levels were measured in household drinking water and enteric pathogen burden was evaluated using multiplex RT-PCR of stool among 131 children from one month to five years of age living in Mirebalais, Haiti. Microbiome profiling was performed using metagenomic sequencing. RESULTS: Most individuals lived in households with undetectable FCR measured in the drinking water (112/131, 86%). Detection of enteric pathogen DNA in stool was common and did not correlate with household water FCR. The infant microbiome in households with detectable FCR demonstrated reduced richness (fewer total number of species, P = 0.04 Kruskall-Wallis test) and less diversity by Inverse Simpson measures (P = 0.05) than households with undetectable FCR. Infants in households with a detectable FCR were more likely to have abundant Bifidobacterium. Using in vitro susceptibility testing, we found that some Bifidobacterium species were resistant to chlorine. CONCLUSIONS: FCR in household drinking water did not correlate with enteric pathogen burden in our study.
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Cloro , Agua Potable , Heces , Microbioma Gastrointestinal , Humanos , Haití/epidemiología , Cloro/farmacología , Agua Potable/microbiología , Lactante , Preescolar , Microbioma Gastrointestinal/efectos de los fármacos , Heces/microbiología , Masculino , Femenino , Purificación del AguaRESUMEN
BACKGROUND: Tuberculosis is a leading cause of death worldwide, and food insecurity is known to negatively influence health outcomes through multiple pathways. Few studies have interrogated the relationship between food insecurity and tuberculosis outcomes, particularly independent of nutrition. METHODS: We conducted a prospective cohort study of adults initiating first-line treatment for clinically suspected or microbiologically confirmed drug-sensitive tuberculosis at a rural referral center in Haiti. We administered a baseline questionnaire, collected clinical data, and analyzed laboratory samples. We used logistic regression models to estimate the relationship between household food insecurity (Household Hunger Scale) and treatment failure or death. We accounted for exclusion of patients lost to follow-up using inverse probability of censoring weighting and adjusted for measured confounders and nutritional status using inverse probability of treatment weighting. RESULTS: We enrolled 257 participants (37% female) between May 2020 and March 2023 with a median age (interquartile range) of 35 (25-45) years. Of these, 105 (41%) had no hunger in the household, 104 (40%) had moderate hunger in the household, and 48 (19%) had severe hunger in the household. Eleven participants (4%) died, and 6 (3%) had treatment failure. After adjustment, food insecurity was significantly associated with subsequent treatment failure or death (odds ratio 5.78 [95% confidence interval, 1.20-27.8]; P = .03). CONCLUSIONS: Household food insecurity at tuberculosis treatment initiation was significantly associated with death or treatment failure after accounting for loss to follow-up, measured confounders, and nutritional status. In addition to the known importance of undernutrition, our findings indicate that food insecurity independently affects tuberculosis treatment outcomes in Haiti.
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Antituberculosos , Inseguridad Alimentaria , Población Rural , Tuberculosis , Humanos , Haití/epidemiología , Femenino , Masculino , Estudios Prospectivos , Adulto , Población Rural/estadística & datos numéricos , Persona de Mediana Edad , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología , Antituberculosos/uso terapéutico , Resultado del Tratamiento , Estado Nutricional , Insuficiencia del TratamientoRESUMEN
BACKGROUND: Food insecurity and undernutrition are related but distinct concepts contributing to poor HIV and tuberculosis outcomes. Pathways linking them with immunologic profile, which may relate to clinical outcomes, remain understudied. METHODS: We analyzed data from a cohort study of 165 antiretroviral therapy (ART)-naïve adults with advanced HIV and newly diagnosed tuberculosis in Botswana from 2009 to 2013. Twenty-nine plasma biomarkers were measured pre-ART and 4 weeks post-ART initiation. We used principal components analysis (PCA) and multivariable linear regression models to assess relationships between immunological profiles and food insecurity (based on the Household Food Insecurity Access Scale), undernutrition (body mass index <18.5 kg/m 2 ), and clinical outcomes. RESULTS: PCA identified 5 principal components with eigenvalues >1. After adjustment, food insecurity was associated with PC3 pre-ART (0.19 per increased category of severity, 95% CI: 0.02 to 0.36) and post-ART (0.24, 95% CI: 0.07 to 0.41). PC3 was driven by higher levels of IFN-α, IFN-γ, interleukin (IL)-12p40, vascular endothelial growth factor, IL-1α, and IL-8 and decreased concentrations of IL-3. Undernutrition was associated with PC5 post-ART (0.49, 95% CI: 0.16 to 0.82). PC5 was driven by higher levels of IL-8, MIP-1α, IL-6, and IL-10 and decreased concentrations in IP-10 and IFN-α. Post-ART PC3 (4.3 percentage point increased risk per increased score of 1, 95% CI: 0.3 to 8.9) and post-ART PC5 (4.8, 95% CI: 0.6 to 8.9) were associated with death in adjusted models. DISCUSSION: We identified 2 distinct immunologic profiles associated with food insecurity, undernutrition, and clinical outcomes in patients with advanced HIV and tuberculosis. Different pathophysiologic processes may link food insecurity and undernutrition with poor outcomes in this vulnerable patient population. Future studies should assess the impact of improving food access and intake on immune function and clinical outcomes.
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Infecciones por VIH , Desnutrición , Tuberculosis , Adulto , Humanos , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Estudios de Cohortes , Interleucina-8/uso terapéutico , Factor A de Crecimiento Endotelial Vascular/uso terapéutico , Desnutrición/complicaciones , Desnutrición/epidemiología , Tuberculosis/complicaciones , Inseguridad Alimentaria , Abastecimiento de AlimentosRESUMEN
Routinely collected testing data have been a vital resource for public health response during the COVID-19 pandemic and have revealed the extent to which Black and Hispanic persons have borne a disproportionate burden of SARS-CoV-2 infections and hospitalizations in the United States. However, missing race and ethnicity data and missed infections due to testing disparities limit the interpretation of testing data and obscure the true toll of the pandemic. We investigated potential bias arising from these 2 types of missing data through a case study carried out in Holyoke, Massachusetts, during the prevaccination phase of the pandemic. First, we estimated SARS-CoV-2 testing and case rates by race and ethnicity, imputing missing data using a joint modeling approach. We then investigated disparities in SARS-CoV-2 reported case rates and missed infections by comparing case rate estimates with estimates derived from a COVID-19 seroprevalence survey. Compared with the non-Hispanic White population, we found that the Hispanic population had similar testing rates (476 tested per 1000 vs 480 per 1000) but twice the case rate (8.1% vs 3.7%). We found evidence of inequitable testing, with a higher rate of missed infections in the Hispanic population than in the non-Hispanic White population (79 infections missed per 1000 vs 60 missed per 1000).
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Prueba de COVID-19 , COVID-19 , Hispánicos o Latinos , SARS-CoV-2 , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Negro o Afroamericano/estadística & datos numéricos , COVID-19/etnología , COVID-19/epidemiología , COVID-19/diagnóstico , Prueba de COVID-19/estadística & datos numéricos , Etnicidad/estadística & datos numéricos , Disparidades en el Estado de Salud , Disparidades en Atención de Salud/etnología , Disparidades en Atención de Salud/estadística & datos numéricos , Hispánicos o Latinos/estadística & datos numéricos , Massachusetts/epidemiología , Diagnóstico Erróneo/estadística & datos numéricos , BlancoRESUMEN
OBJECTIVES: The World Health Organization recommends the use of oral cholera vaccine (OCV) in cholera control efforts. Euvichol®, pre-qualified in 2015, is the leading component of the Global OCV stockpile, but data on its field effectiveness are limited. To evaluate Euvichol® vaccine effectiveness (VE), we conducted a case-control study between September 2018 to March 2020 following an OCV campaign in November 2017 in Haiti. METHODS: Cases were individuals with acute watery diarrhea. Stool samples were tested by culture and real-time polymerase chain reaction of the Vibrio cholerae ctxA gene. Cases were matched to four community controls without diarrhea by residence, enrollment time, age, and gender, and interviewed for sociodemographics, risk factors, and self-reported vaccination. Cholera cases were analyzed by conditional logistic regression in the VE study. Non-cholera diarrhea cases were analyzed in a bias-indicator study. RESULTS: We enrolled 15 cholera cases matched to 60 controls, and 63 non-cholera diarrhea cases matched to 249 controls. In the VE analysis, eight (53%) cases reported vaccination with any number of doses compared to 43 (72%) controls. Adjusted two-dose OCV VE was 69% (95% CI -71 to 94%). CONCLUSIONS: Between 10-27 months after vaccination, Euvichol® was effective and similar to Shanchol™, suggesting that it can serve as one component of multi-sectoral comprehensive cholera control.
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Vacunas contra el Cólera , Cólera , Humanos , Cólera/epidemiología , Cólera/prevención & control , Estudios de Casos y Controles , Haití/epidemiología , Administración Oral , Vacunación , DiarreaRESUMEN
OBJECTIVES: Uncovering and addressing disparities in infectious disease outbreaks require a rapid, methodical understanding of local epidemiology. We conducted a seroprevalence study of SARS-CoV-2 infection in Holyoke, Massachusetts, a majority Hispanic city with high levels of socio-economic disadvantage to estimate seroprevalence and identify disparities in SARS-CoV-2 infection. METHODS: We invited 2000 randomly sampled households between 11/5/2020 and 12/31/2020 to complete questionnaires and provide dried blood spots for SARS-CoV-2 antibody testing. We calculated seroprevalence based on the presence of IgG antibodies using a weighted Bayesian procedure that incorporated uncertainty in antibody test sensitivity and specificity and accounted for household clustering. RESULTS: Two hundred eighty households including 472 individuals were enrolled. Three hundred twenty-eight individuals underwent antibody testing. Citywide seroprevalence of SARS-CoV-2 IgG was 13.1% (95% CI 6.9-22.3) compared to 9.8% of the population infected based on publicly reported cases. Seroprevalence was 16.1% (95% CI 6.2-31.8) among Hispanic individuals compared to 9.4% (95% CI 4.6-16.4) among non-Hispanic white individuals. Seroprevalence was higher among Spanish-speaking households (21.9%; 95% CI 8.3-43.9) compared to English-speaking households (10.2%; 95% CI 5.2-18.0) and among individuals in high social vulnerability index (SVI) areas based on the CDC SVI (14.4%; 95% CI 7.1-25.5) compared to low SVI areas (8.2%; 95% CI 3.1-16.9). CONCLUSIONS: The SARS-CoV-2 IgG seroprevalence in a city with high levels of social vulnerability was 13.1% during the pre-vaccination period of the COVID-19 pandemic. Hispanic individuals and individuals in communities characterized by high SVI were at the highest risk of infection. Public health interventions should be designed to ensure that individuals in high social vulnerability communities have access to the tools to combat COVID-19.
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COVID-19 , Etnicidad , Humanos , Teorema de Bayes , Pandemias , Estudios Seroepidemiológicos , Vulnerabilidad Social , SARS-CoV-2 , Lenguaje , Massachusetts/epidemiología , Anticuerpos Antivirales , Inmunoglobulina GRESUMEN
In Haiti in 2017, the prevalence of serum vibriocidal antibody titers against Vibrio cholerae serogroup O1 among adults was 12.4% in Cerca-la-Source and 9.54% in Mirebalais, suggesting a high recent prevalence of infection. Improved surveillance programs to monitor cholera and guide public health interventions in Haiti are necessary.
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Cólera , Vibrio cholerae O1 , Adulto , Humanos , Haití/epidemiología , Estudios Seroepidemiológicos , Cólera/epidemiología , Salud PúblicaRESUMEN
We report on the sensitivity and specificity of stool culture compared to polymerase chain reaction for detecting Vibrio cholerae in Haiti during the waning period of the initial outbreak in 2018-2019. We found that stool culture (with a sensitivity of 33.3% and specificity of 97.4%) may not be sufficiently robust in this context.
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BACKGROUND: Food insecurity has been independently associated with developing cholera and there is an inverse relationship between national food security and annual cholera incidence. However, the factors that mediate the risk of cholera among food insecure households remain largely unexplored. METHODOLOGY AND PRINCIPAL FINDINGS: In a cross-sectional survey of rural households in Haiti, we explored the role of food behaviors (i.e., dietary choices and food-handling practices) as mediators of cholera risk among food-insecure families. We generated a series of multivariable regression models to test hypothesized associations between the severity of food insecurity (measured by the Household Hunger Scale), hygiene and food behaviors, and history of severe, medically-attended cholera. Moderate household hunger (Adjusted Odds Ratio [AOR] 1.47, 95% Confidence Interval (CI) 1.05-2.04; p = 0.021) and severe hunger (AOR 2.45, 95% CI 1.45-4.15; p = 0.001) were positively associated with a history of severe, medically-attended cholera compared with little to no household hunger. Household hunger was positively associated with three behaviors: antacid use, consumption of leftover non-reheated food, and eating food and beverages prepared outside of the home (i.e., at a restaurant or from a vendor). Consumption of outside food items and antacid use were positively associated with a history of cholera. CONCLUSION: Our findings suggest that food behaviors may mediate the association between food insecurity and cholera and contribute to an understanding of how interventions could be designed to target food insecurity as part of cholera prevention and control.
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Cólera , Humanos , Estudios Transversales , Cólera/epidemiología , Antiácidos , Abastecimiento de Alimentos , Inseguridad AlimentariaRESUMEN
Point-of-care antigen-detecting rapid diagnostic tests (RDTs) to detect Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) represent a scalable tool for surveillance of active SARS-CoV-2 infections in the population. Data on the performance of these tests in real-world community settings are paramount to guide their implementation to combat the COVID-19 pandemic. We evaluated the performance characteristics of the CareStart COVID-19 Antigen test (CareStart) in a community testing site in Holyoke, Massachusetts. We compared CareStart to a SARS-CoV-2 reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) reference, both using anterior nasal swab samples. We calculated the sensitivity, specificity, and the expected positive and negative predictive values at different SARS-CoV-2 prevalence estimates. We performed 666 total tests on 591 unique individuals. 573 (86%) were asymptomatic. There were 52 positive tests by RT-qPCR. The sensitivity of CareStart was 49.0% (95% Confidence Interval (CI) 34.8-63.4) and specificity was 99.5% (95% CI 98.5-99.9). Among positive RT-qPCR tests, the median cycle threshold (Ct) was significantly lower in samples that tested positive on CareStart. Using a Ct ≤ 30 as a benchmark for positivity increased the sensitivity of the test to 64.9% (95% CI 47.5-79.8). Our study shows that CareStart has a high specificity and moderate sensitivity. The utility of RDTs, such as CareStart, in mass implementation should prioritize use cases in which a higher specificity is more important, such as triage tests to rule-in active infections in community surveillance programs.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Pandemias , COVID-19/diagnóstico , COVID-19/epidemiología , Sensibilidad y Especificidad , Prueba de COVID-19RESUMEN
Early detection of SARS-CoV-2 infection is crucial to prevent its spread. This study aimed to document test sensitivity/specificity, correlation with cycle threshold value from polymerase chain reaction (PCR), fitness-for-use in different populations and settings, and user perspectives that could inform large-scale implementation. In this study, we evaluated the performance of a rapid antigen detection test, BD Veritor, and compared this (and another rapid test, Standard Q) against reverse transcription PCR (RT-PCR) in terms of sensitivity and specificity in 130 symptomatic and 130 asymptomatic adults. In addition, we evaluated the suitability and ease of use of the BD Veritor test in a subsample of study participants (n = 42) and implementers (n = 5). At 95% confidence interval, the sensitivity of the BD Veritor and Standard Q test were 70% and 63% in symptomatic and 87% and 73% in asymptomatic individuals, respectively, regarding positive SARS-CoV-2 RT-PCR results. Overall, the BD Veritor test was 78% sensitive and 99.5% specific compared with RT-PCR irrespective of the cycle threshold. This warrants large field evaluation as well as use of the rapid antigen test for quick assessment of SARS-CoV-2 for containment of epidemics in the country.
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COVID-19 , SARS-CoV-2 , Adulto , Antígenos Virales , Bangladesh/epidemiología , COVID-19/diagnóstico , Prueba de COVID-19 , Humanos , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Contact tracing is used for multiple infectious diseases, most recently for COVID-19, but data regarding its effectiveness in disease control are scarce. To address this knowledge gap and inform public health decision making for COVID-19, we systematically reviewed the existing literature to determine the effectiveness of contact tracing in the control of communicable illness. METHODS: We searched PubMed, Embase, and the Cochrane Library from database inception up to Nov 22, 2021, for published studies evaluating associations between provider-initiated contact tracing for transmissible infectious diseases and one of three outcomes of interest: case detection rates among contacts or at the community level, overall forward transmission, or overall disease incidence. Clinical trials and observational studies were eligible, with no language or date restrictions. Reference lists of reviews were searched for additional studies. We excluded studies without a control group, using only mathematical modelling, not reporting a primary outcome of interest, or solely examining patient-initiated contact tracing. One reviewer applied eligibility criteria to each screened abstract and full-text article, and two reviewers independently extracted summary effect estimates and additional data from eligible studies. Only data reported in published manuscripts or supplemental material was extracted. Risk of bias for each included study was assessed with the Cochrane Risk of Bias 2 tool (randomised studies) or the Newcastle-Ottawa Scale (non-randomised studies). FINDINGS: We identified 9050 unique citations, of which 47 studies met the inclusion criteria: six were focused on COVID-19, 20 on tuberculosis, eight on HIV, 12 on curable sexually transmitted infections (STIs), and one on measles. More than 2 million index patients were included across a variety of settings (both urban and rural areas and low-resource and high-resource settings). Of the 47 studies, 29 (61·7%) used observational designs, including all studies on COVID-19, and 18 (38·3%) were randomised controlled trials. 40 studies compared provider-initiated contact tracing with other interventions or evaluated expansions of provider-initiated contact tracing, and seven compared programmatic adaptations within provider-initiated contact tracing. 29 (72·5%) of the 40 studies evaluating the effect of provider-initiated contact tracing, including four (66·7%) of six COVID-19 studies, found contact tracing interventions were associated with improvements in at least one outcome of interest. 23 (48·9%) studies had low risk of bias, 22 (46·8%) studies had some risk of bias, and two (4·3%) studies (both randomised controlled trials on curable STIs) had high risk of bias. INTERPRETATION: Provider-initiated contact tracing can be an effective public health tool. However, the ability of authorities to make informed choices about its deployment might be limited by heterogenous approaches to contact tracing in studies, a scarcity of quantitative evidence on its effectiveness, and absence of specificity of tracing parameters most important for disease control. FUNDING: The Sullivan Family Foundation, Massachusetts General Hospital Executive Committee on Research, and US National Institutes of Health.
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COVID-19/epidemiología , Enfermedades Transmisibles/epidemiología , Trazado de Contacto/estadística & datos numéricos , Salud Pública , Humanos , Enfermedades de Transmisión Sexual/epidemiología , Tuberculosis/epidemiologíaRESUMEN
Diarrheal illness is a major cause of morbidity and mortality among children in Haiti, and the impact of diarrheal illness was compounded by a cholera outbreak between 2010 and 2019. Our understanding of risk factors for diarrhea among children during this outbreak is limited. We conducted a secondary analysis of data collected as part of a cholera vaccine effectiveness study to identify factors associated with medically attended diarrhea among children in central Haiti from October of 2012 through November of 2016. We identified 47 children aged one to five years old who presented to medical clinics with acute, watery diarrhea, and 166 matched controls who did not have diarrhea, and we performed conditional logistic regression to identify factors associated with diarrhea. Discontinuing exclusive breastfeeding within one month of birth was associated with increased risk of diarrhea (RR 6.9, 95% CI 1.46-32.64), and diarrhea was inversely associated with reported history of supplementation with vitamin A (RR 0.05, 95% CI 0.004-0.56) and zinc (reported among 0% of cases vs. 17% of controls). Because of the concordance in supplementation patterns, it was not possible to attribute the association to vitamin A or zinc independently. While having a respondent who correctly identified ≥3 means of avoiding cholera was associated with reduced risk of diarrhea (RR 0.43, 95% CI 0.19-1.01), reported household sanitation practices and knowledge of cholera were not consistently associated with risk of diarrhea. These findings support ongoing efforts to reduce barriers to breastfeeding and promote pediatric supplementation with vitamin A and zinc in Haiti. Given the reduced efficacy of current oral cholera vaccines (OCV) among children, the results reinforce the importance of breastfeeding and micronutrient supplementation in preventing all-cause pediatric diarrheal illness generally and during cholera outbreaks.
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Vacunas contra el Cólera/administración & dosificación , Cólera/prevención & control , Diarrea/prevención & control , Estudios de Casos y Controles , Preescolar , Cólera/epidemiología , Cólera/microbiología , Diarrea/epidemiología , Diarrea/microbiología , Epidemias , Femenino , Haití/epidemiología , Humanos , Lactante , Masculino , Población Rural/estadística & datos numéricos , Eficacia de las Vacunas , Vibrio cholerae/genética , Vibrio cholerae/inmunologíaRESUMEN
BACKGROUND: The connection between food insecurity and HIV outcomes is well established. The Supplemental Nutrition Assistance Program (SNAP), the primary food safety net program in the United States, may have collateral impacts on HIV incidence. "Broad-based categorical eligibility" for SNAP is a policy that provides a mechanism for states to increase the income or asset limits for SNAP eligibility. METHODS: We estimated the association between the number of new HIV diagnoses in 2010-2014 for each state and (1) state income limits and (2) state asset limits for SNAP eligibility. We fitted multivariable negative binomial regression models with number of HIV diagnoses specified as the outcome; SNAP policies as the primary explanatory variable of interest; state and year fixed effects; and time-varying covariates related to the costs of food, health care, housing, employment, other SNAP policies, and Temporary Assistance for Needy Families spending. RESULTS: HIV diagnoses within states had a statistically significant association with state income limits for SNAP eligibility (incidence rate ratio [IRR], 0.94 per increase in the income limit by 35% of federal poverty level; 95% CI, 0.91-0.98), but no association with state asset limits (increased asset limit vs no change: IRR, 1.02; 95% CI, 0.94-1.10; eliminated asset limit vs no change: IRR, 1.04; 95% CI, 0.99-1.10). CONCLUSIONS: State income limits for SNAP eligibility were inversely associated with the number of new HIV diagnoses for states between 2010 and 2014. Proposals to eliminate the use of broad-based categorical eligibility to increase the income limit for SNAP may undercut efforts to end the HIV epidemic in the United States.
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The movement to decolonize global health and address power inequities among its actors is not new. Founded on the work of colonized and marginalized people themselves, initiatives at universities, schools of public health, and international development organizations have emerged to call for anti-racism and anti-colonialism within the field. US Academic Medical Centers (AMCs) have been less vocal in this wider discussion, despite their large engagement in the field through clinical, research, and medical education activities. As global health practitioners currently based at an AMC, we believe that it is important to critically evaluate our practices. We therefore propose three starting questions for our colleagues and students to consider and act upon as they adopt and navigate a praxis in anti-racism and anti-colonialism as foundational principles in global health. These questions call on us to closely examine the legacies of racism and colonialism in global health, the value placed on different ways of knowing in this field, and our motivations for engaging in this work. They are presented as a tool to reexamine global health, challenging the constructed binary of the "global South" and "global North," and the perceived ideas of poverty and resource scarcity as the natural immutable reality of the global South.
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Colonialismo , Salud Global , Racismo , Centros Médicos Académicos , Humanos , Conocimiento , Motivación , Estados UnidosRESUMEN
Cholera caused by Vibrio cholerae O139 could reemerge, and proactive development of an effective O139 vaccine would be prudent. To define immunoreactive and potentially immunogenic carbohydrate targets of Vibrio cholerae O139, we assessed immunoreactivities of various O-specific polysaccharide (OSP)-related saccharides with plasma from humans hospitalized with cholera caused by O139, comparing responses to those induced in recipients of a commercial oral whole-cell killed bivalent (O1 and O139) cholera vaccine (WC-O1/O139). We also assessed conjugate vaccines containing selected subsets of these saccharides for their ability to induce protective immunity using a mouse model of cholera. We found that patients with wild-type O139 cholera develop IgM, IgA, and IgG immune responses against O139 OSP and many of its fragments, but we were able to detect only a moderate IgM response to purified O139 OSP-core, and none to its fragments, in immunologically naive recipients of WC-O1/O139. We found that immunoreactivity of O139-specific polysaccharides with antibodies elicited by wild-type infection markedly increase when saccharides contain colitose and phosphate residues, that a synthetic terminal tetrasaccharide fragment of OSP is more immunoreactive and protectively immunogenic than complete OSP, that native OSP-core is a better protective immunogen than the synthetic OSP lacking core, and that functional vibriocidal activity of antibodies predicts in vivo protection in our model but depends on capsule thickness. Our results suggest that O139 OSP-specific responses are not prominent following vaccination with a currently available oral cholera vaccine in immunologically naive humans and that vaccines targeting V. cholerae O139 should be based on native OSP-core or terminal tetrasaccharide. IMPORTANCE Cholera is a severe dehydrating illness of humans caused by Vibrio cholerae serogroup O1 or O139. Protection against cholera is serogroup specific, and serogroup specificity is defined by O-specific polysaccharide (OSP). Little is known about immunity to O139 OSP. In this study, we used synthetic fragments of the O139 OSP to define immune responses to OSP in humans recovering from cholera caused by V. cholerae O139, compared these responses to those induced by the available O139 vaccine, and evaluated O139 fragments in next-generation conjugate vaccines. We found that the terminal tetrasaccharide of O139 is a primary immune target but that the currently available bivalent cholera vaccine poorly induces an anti-O139 OSP response in immunologically naive individuals.
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Anticuerpos Antibacterianos/sangre , Vacunas contra el Cólera/inmunología , Cólera/prevención & control , Antígenos O/inmunología , Vibrio cholerae O139/inmunología , Adolescente , Adulto , Anciano , Animales , Niño , Cólera/inmunología , Vacunas contra el Cólera/administración & dosificación , Convalecencia , Modelos Animales de Enfermedad , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Ratones , Persona de Mediana Edad , Vacunación , Vacunas Combinadas/administración & dosificación , Vacunas Combinadas/inmunología , Vacunas Conjugadas/administración & dosificación , Vacunas Conjugadas/inmunología , Vacunas Conjugadas/normas , Adulto JovenRESUMEN
BACKGROUND: Isolation of hospitalized persons under investigation (PUIs) for coronavirus disease 2019 (COVID-19) reduces nosocomial transmission risk. Efficient evaluation of PUIs is needed to preserve scarce healthcare resources. We describe the development, implementation, and outcomes of an inpatient diagnostic algorithm and clinical decision support system (CDSS) to evaluate PUIs. METHODS: We conducted a pre-post study of CORAL (COvid Risk cALculator), a CDSS that guides frontline clinicians through a risk-stratified COVID-19 diagnostic workup, removes transmission-based precautions when workup is complete and negative, and triages complex cases to infectious diseases (ID) physician review. Before CORAL, ID physicians reviewed all PUI records to guide workup and precautions. After CORAL, frontline clinicians evaluated PUIs directly using CORAL. We compared pre- and post-CORAL frequency of repeated severe acute respiratory syndrome coronavirus 2 nucleic acid amplification tests (NAATs), time from NAAT result to PUI status discontinuation, total duration of PUI status, and ID physician work hours, using linear and logistic regression, adjusted for COVID-19 incidence. RESULTS: Fewer PUIs underwent repeated testing after an initial negative NAAT after CORAL than before CORAL (54% vs 67%, respectively; adjusted odd ratio, 0.53 [95% confidence interval, .44-.63]; Pâ <â .01). CORAL significantly reduced average time to PUI status discontinuation (adjusted difference [standard error], -7.4 [0.8] hours per patient), total duration of PUI status (-19.5 [1.9] hours per patient), and average ID physician work-hours (-57.4 [2.0] hours per day) (all Pâ <â .01). No patients had a positive NAAT result within 7 days after discontinuation of precautions via CORAL. CONCLUSIONS: CORAL is an efficient and effective CDSS to guide frontline clinicians through the diagnostic evaluation of PUIs and safe discontinuation of precautions.