Missing data and missed infections: investigating racial and ethnic disparities in SARS-CoV-2 testing and infection rates in Holyoke, Massachusetts.

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).

Disparities in SARS-CoV-2 Infection by Race, Ethnicity, Language, and Social Vulnerability: Evidence from a Citywide Seroprevalence Study in Massachusetts, USA.

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.

Effectiveness of the Euvichol® oral cholera vaccine at 2 years: A case-control and bias-indicator study in Haiti.

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.

Seroprevalence of Vibrio cholerae in Adults, Haiti, 2017.

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.

Poor Sensitivity of Stool Culture Compared to Polymerase Chain Reaction in Surveillance for Vibrio cholerae in Haiti, 2018-2019.

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.

Food insecurity and risk of cholera: A cross-sectional study and exploratory analysis of potential mediators.

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.

Anti-Racism and Anti-Colonialism Praxis in Global Health-Reflection and Action for Practitioners in US Academic Medical Centers.

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.

'It was a ravage!': lived experiences of epidemic cholera in rural Haiti.

Introduction: A cholera epidemic began in Haiti over 8 years ago, prompting numerous, largely quantitative research studies. Assessments of local 'knowledge, attitudes and practices' relevant for cholera control have relied primarily on cross-sectional surveys. The voices of affected Haitians have rarely been elevated in the scientific literature on the topic. Methods: We undertook focus groups with stakeholders in the Artibonite region of Haiti in 2011, as part of planning for a public health intervention to control cholera at the height of the epidemic. In this study, we coded and analysed themes from 55 community members in five focus groups, focusing on local experiences of cholera and responses to the prevention messages. Results: The majority of participants had a personal experience with cholera and described its spread in militaristic terms, as a disease that 'attacked' individuals, 'ravaged' communities and induced fear. Pre-existing structural deficiencies were identified as increasing the risk of illness and death. Knowledge of public health messages coincided with some improvements in water treatment and handwashing, but not changes in open defecation in their community, and was sometimes associated with self-blame or shame. Most participants cited constrained resources, and a minority listed individual neglect, for inconsistent or unimproved practices. Conclusion: The experience of epidemic cholera in a rural Haitian community at the beginning of a major outbreak included a high burden and was exacerbated by poverty, which increased risk while hindering practice of known prevention messages. To interrupt cholera transmission, public health education must be paired with investments in structural improvements that expand access to prevention and healthcare services.