Seroincidence of SARS-CoV-2 infection prior to and during the rollout of vaccines in a community-based prospective cohort of U.S. adults (preprint)

Background Infectious disease surveillance systems, which largely rely on diagnosed cases, underestimate the true incidence of SARS-CoV-2 infection, due to under-ascertainment and underreporting. We used repeat serologic testing to measure N-protein seroconversion in a well-characterized cohort of U.S. adults with no serologic evidence of SARS-CoV-2 infection to estimate the incidence of SARS-CoV-2 infection and characterize risk factors, with comparisons before and after the start of the SARS-CoV-2 vaccine and variant eras. Methods We assessed the incidence rate of infection and risk factors in two sub-groups (cohorts) that were SARS-CoV-2 N-protein seronegative at the start of each follow-up period: 1) the pre-vaccine/wild-type era cohort (n=3,421), followed from April to November 2020; and 2) the vaccine/variant era cohort (n=2,735), followed from November 2020 to June 2022. Both cohorts underwent repeat serologic testing with an assay for antibodies to the SARS-CoV-2 N protein (Bio-Rad Platelia SARS-CoV-2 total Ab). We estimated crude incidence and sociodemographic/epidemiologic risk factors in both cohorts. We used multivariate Poisson models to compare the risk of SARS-CoV-2 infection in the pre-vaccine/wild-type era cohort (referent group) to that in the vaccine/variant era cohort, within strata of vaccination status and epidemiologic risk factors (essential worker status, child in the household, case in the household, social distancing). Findings In the pre-vaccine/wild-type era cohort, only 18 of the 3,421 participants (0.53%) had >1 vaccine dose by the end of follow-up, compared with 2,497/2,735 (91.3%) in the vaccine/variant era cohort. We observed 323 and 815 seroconversions in the pre-vaccine/wild-type era and the vaccine/variant era and cohorts, respectively, with corresponding incidence rates of 9.6 (95% CI: 8.3-11.5) and 25.7 (95% CI: 24.2-27.3) per 100 person-years. Associations of sociodemographic and epidemiologic risk factors with SARS-CoV-2 incidence were largely similar in the pre-vaccine/wild-type and vaccine/variant era cohorts. However, some new epidemiologic risk factors emerged in the vaccine/variant era cohort, including having a child in the household, and never wearing a mask while using public transit. Adjusted incidence rate ratios (aIRR), with the entire pre-vaccine/wild-type era cohort as the referent group, showed markedly higher incidence in the vaccine/variant era cohort, but with more vaccine doses associated with lower incidence: aIRRun/undervaccinated=5.3 (95% CI: 4.2-6.7); aIRRprimary series only=5.1 (95% CI: 4.2-7.3); aIRRboosted once=2.5 (95% CI: 2.1-3.0), and aIRRboosted twice=1.65 (95% CI: 1.3-2.1). These associations were essentially unchanged in risk factor-stratified models. Interpretation In SARS-CoV-2 N protein seronegative individuals, large increases in incidence and newly emerging epidemiologic risk factors in the vaccine/variant era likely resulted from multiple co-occurring factors, including policy changes, behavior changes, surges in transmission, and changes in SARS-CoV-2 variant properties. While SARS-CoV-2 incidence increased markedly in most groups in the vaccine/variant era, being up to date on vaccines and the use of non-pharmaceutical interventions (NPIs), such as masking and social distancing, remained reliable strategies to mitigate the risk of SARS-CoV-2 infection, even through major surges due to immune evasive variants. Repeat serologic testing in cohort studies is a useful and complementary strategy to characterize SARS-CoV-2 incidence and risk factors.

Parental COVID-19 vaccine hesitancy and vaccine uptake among children and adolescents in the US: Findings from a prospective national cohort (preprint)

Objectives: Our aim was to measure COVID-19 vaccine uptake among children aged 5-17 years old via parents participating in the CHASING COVID Cohort and identify sociodemographic factors associated with it. Methods: In this longitudinal study, parents of school-aged children were asked about their own vaccination status and that of their children at three time points between June 2021-January 2022, along with reasons for vaccinating immediately or delaying vaccinations for their children. Multivariable log binomial models were used to identify correlates of vaccine uptake among children. Results: Of the 1,583 children aged 5-17 years, 64.9% were vaccinated. Over 40% of parents of 5-11 year old children who intended to delay vaccinating their child in June 2021 had still not vaccinated them by January 2022, including 30% of the parents who were vaccinated. After adjusting for measured confounders, parental vaccination status was associated with higher likelihood of children's vaccine uptake (age-specific adjusted odds ratios [aORs]: aOR16-17 3.7, 95% CI 2.3, 5.9, aOR12-15 3.7, 95% CI 2.6, 5.3; aOR5-11 10.6, 95% CI 5.4, 20.9). Parental education (aOR16-17 1.4, 95% CI 1.1, 1.8, aOR12-15 1.5, 95% CI 1.2, 1.9; aOR5-11 2.1, 95% CI 1.5, 2.9) and worry about others getting infected (aOR5-11 1.4, 95% CI 1.1, 1.6) were also associated with higher vaccine uptake among children. A higher proportion of parents of 5-11 year olds (vs. 12-17 year olds) had concerns about vaccine safety and effectiveness. Conclusion: To increase vaccination coverage among young children, vaccination campaigns should focus on both vaccinated and unvaccinated parents and messaging should be specific to the child's age.

Food Insecurity During the First Year of COVID-19: An Analysis of Employment and Sociodemographic Factors Among a Longitudinal Cohort (CHASING COVID) (preprint)

Objectives While much has been reported about the impact of COVID-19 on U.S. food insecurity, longitudinal data and the variability experienced by people working in different industries are limited. This study aims to further characterize individuals experiencing food insecurity during the pandemic in terms of employment and sociodemographic characteristics and degree of food insecurity. Methods The study sample consisted of people enrolled in a U.S. prospective cohort study (CHASING COVID) who completed all food insecurity questionnaires from Visit 1 (April-July 2020) through Visit 7 (May-June 2021). Descriptive statistics and logistic regression models were used to determine employment and sociodemographic correlates of food insecurity (using a screening question from the USDA HFSS). Patterns of food insecurity and utilization of food benefit programs were also examined. Results Thirty-one percent (1251/4019) of the sample were food insecure. Black and Hispanic respondents, households with children, and those with lower income and education levels had a higher odds of food insecurity. People employed in construction, leisure/hospitality and trade/transportation industries had the highest burden of both food insecurity and income loss. Among those reporting food insecurity, 40% were persistently food insecure ([≥]4 consecutive visits), and 46% did not utilize any food benefit programs. Conclusions The pandemic resulted in widespread food insecurity in our cohort, much of which was persistent. In addition to addressing sociodemographic disparities, future policies should focus on the needs of those working in vulnerable industries and ensure those experiencing food insecurity can easily participate in food benefit programs for which they are eligible.

The epidemiology of long COVID in US adults two years after the start of the US SARS-CoV-2 pandemic (preprint)

Objectives To characterize prevalence and impact of long COVID. Methods We conducted a population-representative survey, June 30-July 2, 2022, of a random sample of 3,042 United States adults. Using questions developed by the United Kingdom’s Office of National Statistics, we estimated the prevalence by sociodemographics, adjusting for gender and age. Results An estimated 7.3% (95% CI: 6.1-8.5%) of all respondents reported long COVID, approximately 18,533,864 adults. One-quarter (25.3% [18.2-32.4%]) of respondents with long COVID reported their day-to-day activities were impacted ‘a lot’ and 28.9% had SARS-CoV-2 infection >12 months ago. The prevalence of long COVID was higher among respondents who were female (aPR: 1.84 [1.40-2.42]), had comorbidities (aPR: 1.55 [1.19-2.00]) or were not (versus were) boosted (aPR: 1.67 [1.19-2.34]) or not vaccinated (versus boosted) (aPR: 1.41 (1.05-1.91)). Conclusions We observed a high burden of long COVID and substantial variability in prevalence of SARS-CoV-2. Population-based surveys are an important surveillance tool and supplement to ongoing efforts to monitor long COVID.

The prevalence of SARS-CoV-2 infection and long COVID in US adults during the BA.5 surge, June-July 2022 (preprint)

Due to changes in SARS-CoV-2 testing practices, passive case-based surveillance may be an increasingly unreliable indicator for monitoring the burden of SARS-CoV-2, especially during surges. We conducted a cross-sectional survey of a population-representative sample of 3,042 U.S. adults between June 30 and July 2, 2022, during the Omicron BA.5 surge. Respondents were asked about SARS-CoV-2 testing and outcomes, COVID-like symptoms, contact with cases, and experience with prolonged COVID-19 symptoms following prior infection. We estimated the weighted age and sex-standardized SARS-CoV-2 prevalence, during the 14-day period preceding the interview. We estimated age and gender adjusted prevalence ratios (aPR) for current SARS-CoV-2 infection using a log-binomial regression model. An estimated 17.3% (95% CI 14.9, 19.8) of respondents had SARS-CoV-2 infection during the two-week study period, equating to 44 million cases as compared to 1.8 million per the CDC during the same time period. SARS-CoV-2 prevalence was higher among those 18-24 years old (aPR 2.2, 95% CI 1.8, 2.7) and among non-Hispanic Black (aPR 1.7, 95% CI 1.4 ,2.2) and Hispanic (aPR 2.4, 95% CI 2.0 , 2.9). SARS-CoV-2 prevalence was also higher among those with lower income (aPR 1.9, 95% CI 1.5, 2.3), lower education (aPR 3.7 95% CI 3.0,4.7), and those with comorbidities (aPR 1.6, 95% CI 1.4, 2.0). An estimated 21.5% (95% CI 18.2, 24.7) of respondents with a SARS-CoV-2 infection more than 4 weeks prior reported long COVID symptoms. The inequitable distribution of SARS-CoV-2 prevalence during the BA.5 surge will likely drive inequities in the future burden of long COVID.

The prevalence of SARS-CoV-2 infection and uptake of COVID-19 antiviral treatments during the BA.2/BA.2.12.1 surge, New York City, April-May 2022 (preprint)

Importance: Routine case surveillance data for SARS-CoV-2 are incomplete, biased, missing key variables of interest, and may be unreliable for both timely surge detection and understanding the burden of infection. Objective: To determine the prevalence of SARS-CoV-2 infection during the Omicron BA.2/BA.2.12.1 surge in relation to official case counts, and to assess the epidemiology of infection and uptake of SARS-CoV-2 antivirals. Design: Cross-sectional survey of a representative sample of New York City (NYC) adult residents, conducted May 7-8, 2022. Setting: NYC, April 23-May 8, 2022, during which the official SARS-CoV-2 case count was 49,253 and BA.2.12.2 comprised 20% of reported cases. Participants: A representative sample of 1,030 NYC adult residents >18 years. Exposure(s): Vulnerability to severe COVID-19, including vaccination/booster status, prior COVID, age, and presence of comorbidities. Main Outcome(s) and Measure(s): Prevalence of SARS-CoV-2 infection during a 14-day period, weighted to represent the NYC adult population. Respondents self-reported on SARS-CoV-2 testing (including at-home rapid antigen tests), testing outcomes, COVID-like symptoms, and contact with confirmed/probable cases. Individuals with SARS-CoV-2 were asked about awareness/use of antiviral medications. Results: An estimated 22.1% (95%CI 17.9%-26.2%) of respondents had SARS-CoV-2 infection during the study period, corresponding to ~1.5 million adults (95%CI 1.3-1.8 million). Prevalence was estimated at 34.9% (95%CI 26.9%- 42.8%) among individuals with co-morbidities, 14.9% (95% CI 11.0%-18.8%) among those 65+ years, and 18.9% (95%CI 10.2%-27.5%) among unvaccinated persons. Hybrid protection against severe disease (i.e., from both vaccination and prior infection) was 66.2% (95%CI 55.7%-76.7%) among those with COVID and 46.3% (95%CI 40.2-52.2) among those without. Among individuals with COVID, 55.9% (95%CI 44.9%- 67.0%) were not aware of the antiviral nirmatrelvir/ritonavir (PaxlovidTM), and 15.1% (95%CI 7.1%-23.1%) reported receiving it. Conclusions and Relevance: The true magnitude of NYCs BA.2/BA.2.12.1 surge was vastly underestimated by routine SARS-CoV-2 surveillance. Until there is more certainty that the impact of future pandemic surges on severe population health outcomes will be diminished, representative surveys are needed for timely surge detection, and to estimate the true burden of infection, hybrid protection, and uptake of time-sensitive treatments.

Design and implementation of a global site assessment survey among HIV clinics participating in the International epidemiology Databases to Evaluate AIDS (IeDEA) research consortium (preprint)

Introduction Timely descriptions of HIV service characteristics and their evolution over time across diverse settings are important for monitoring the scale-up of evidence-based program strategies, understanding the implementation landscape, and examining service delivery factors that influence HIV care outcomes. Methods The International epidemiology Databases to Evaluate AIDS (IeDEA) consortium undertakes periodic cross-sectional surveys on service availability and care at participating HIV treatment sites to characterize trends and inform the scientific agenda for HIV care and implementation science communities. IeDEA’s 2020 general site assessment survey was developed through a consultative, 18-month process that engaged diverse researchers in identifying content from previous surveys that should be retained for longitudinal analyses and in developing expanded and new content to address gaps in the literature. An iterative review process was undertaken to standardize the format of new survey questions and align them with best practices in survey design and measurement and lessons learned through prior IeDEA site assessment surveys. Results The survey questionnaire developed through this process included eight content domains covered in prior surveys (patient population, staffing and community linkages, HIV testing and diagnosis, new patient care, treatment monitoring and retention, routine HIV care and screening, pharmacy, record-keeping and patient tracing), along with expanded content related to antiretroviral therapy (differentiated service delivery and roll-out of dolutegravir-based regimens); mental health and substance use disorders; care for pregnant/postpartum women and HIV-exposed infants; tuberculosis preventive therapy; and pediatric/adolescent tuberculosis care; and new content related to Kaposi’s sarcoma diagnostics, the impact of COVID-19 on service delivery, and structural barriers to HIV care. The survey was distributed to 238 HIV treatment sites in late 2020, with a 95% response rate. Conclusion IeDEA’s approach for site survey development approach has broad relevance for HIV research networks and other priority health conditions.

Estimating the period prevalence of SARS-CoV-2 infection during the Omicron (BA.1) surge in New York City (NYC), January 1-March 16, 2022 (preprint)

In a population-based survey of NYC adults, we assessed positive SARS-CoV-2 tests (including via exclusive at-home testing) and possible cases among untested respondents. An estimated 27.4% (95%CI: 22.8%-32.0%) or 1.8 million adults (95%CI: 1.6-2.1 million) had SARS-CoV-2 infection. SARS-CoV-2 prevalence was high among groups that are more vulnerable to severe SARS-CoV-2 and death, including unvaccinated persons (21.7%, 95%CI 9.6%-33.8%) and those aged 65+ (17.8%, 95%CI 10.2-25.4%). Population-based representative surveys are an important adjunct surveillance tool to standard testing-based SARS-CoV-2 surveillance.

Effectiveness of Covid-19 vaccines against symptomatic and asymptomatic SARS-CoV-2 infections in an urgent care setting (preprint)

Background It is critical to monitor changes in vaccine effectiveness against COVID-19 outcomes for various vaccine products in different population subgroups. Methods We conducted a retrospective study in patients ≥12 years who underwent testing for the SARS-CoV-2 virus from April 1 - October 25, 2021 at urgent care centers in the New York City metropolitan area. Patients self-reported vaccination status at the time of testing. We used a test-negative design to estimate vaccine effectiveness (VE) by comparing odds of a positive test for SARS-CoV-2 infection among vaccinated (n=484,468), partially vaccinated (n=107,573 ) , and unvaccinated (n=466,452) patients, adjusted for demographic factors and calendar time. Results VE against symptomatic infection after 2 doses of mRNA vaccines was 96% (95% Confidence Interval [CI]: 95%, 97%) in the pre-delta period and reduced to 79% (95% CI: 77%, 81%) in the delta period. In the delta period, VE for 12–15-year-olds (85%; [95% CI: 81%, 89%]) was higher compared to older age groups (<65% for all other age groups). VE estimates did not differ by sex, race/ethnicity, and comorbidity. VE against symptomatic infection was the highest for individuals with a prior infection followed by full vaccination. VE against symptomatic infection after the mRNA-1273 vaccine (83% [95% CI: 81%, 84%]) was higher compared to the BNT162b2 vaccine (76% [95% CI: 74%, 78%]) in the delta period. VE after the single-dose Ad26.COV2.S vaccine was the lowest compared to other vaccines (29% [95% CI: 26%, 32%]) in the delta period. Conclusions VE against infection after two doses of the mRNA vaccine was high initially, but significantly reduced against the delta variant for all three FDA-approved vaccines.

Racial/ethnic disparities in exposure to COVID-19, susceptibility to COVID-19 and access to health care - findings from a U.S. national cohort (preprint)

We examined the influence of racial/ethnic differences in socioeconomic position on COVID-19 seroconversion and hospitalization within a community-based prospective cohort enrolled in March 2020 and followed through October 2021 (N=6740). The ability to social distance as a measure of exposure to COVID-19, susceptibility to COVID-19 complications, and access to healthcare varied by race/ethnicity with non-white participants having more exposure risk and more difficulty with healthcare access than white participants. Participants with more (versus less) exposure had greater odds of seroconversion (aOR:1.64, 95% Confidence Interval [CI] 1.18-2.29). Participants with more susceptibility and more barriers to healthcare had greater odds of hospitalization (respective aOR:2.36; 1.90-2.96 and 2.31; 1.69-2.68). Race/ethnicity positively modified the association between susceptibility and hospitalization (aORnon-White:2.79, 2.06-3.78). Findings may explain the disproportionate burden of COVID-19 infections and complications among Hispanic and non-Hispanic Black persons. Primary and secondary prevention efforts should address disparities in exposure, COVID-19 vaccination, and treatment.

SARS-CoV-2 Pandemic in New York Metropolitan Area: The View from a Major Urgent Care Provider (preprint)

Purpose: Tracking SARS-CoV-2 testing and positivity trends is crucial for understanding the trajectory of the pandemic. We describe demographic and clinical characteristics, testing, and positivity rates for SARS-CoV-2 among 2.8 million patients evaluated at an urgent care provider.Methods: We conducted a retrospective study of patients receiving a diagnostic or serologic test for SARS-CoV-2 between March 1, 2020 and July 20, 2021 at 115 CityMD locations in the New York metropolitan area. Temporal trends in SARS-CoV-2 positivity by diagnostic and serologic tests stratified by age, sex, race/ethnicity, and borough of residence were assessed.Results: During the study period, 6.1 million COVID diagnostic and serological tests were performed on 2.8 million individuals. Testing levels were higher among 20-29 year old, non-Hispanic White, and female patients compared with other groups. About 35% were repeat testers. RT-PCR positivity was higher in non-Hispanic Black (7.9%), Hispanic (8.2%), and Native American (8.2%) compared to non-Hispanic White (5.7%) patients. Overall seropositivity was estimated to be 22.1% (95% Confidence Interval [CI]: 22.0, 22.2) and was highest among 10–14-year-olds (27.9%), and non-Hispanic Black (26.0%) and Hispanic (31.0%) testers.Conclusion: Urgent care centers can provide broad access to diagnostic testing and critical evaluation for ambulatory patients during pandemics, especially in population-dense, urban epicenters. Urgent care center EMR data can provide in-depth surveillance during pandemics complementary to citywide health department data sources.

Parental plans to vaccinate children for COVID-19 in New York City (preprint)

Once COVID-19 vaccines are approved for children <12 years of age, high pediatric vaccination coverage will be needed to help minimize the public health threat from the SARS-CoV-2 epidemic. We conducted an online survey of 1,119 parents and caregivers of children ≤12 years in New York City from March 9 to April 11, 2021. Among parents surveyed, 61.9% reported plans to vaccinate their youngest child for COVID-19, 14.8% said they do not plan to vaccinate their child and 23.3% were unsure. Female and non-Hispanic Black parents were least likely to report plans to vaccinate their children. Safety, effectiveness and perceptions that children do not need vaccination were the primary reasons for vaccine hesitancy/resistance. Parents who have or will vaccinate themselves were significantly more likely to report they would vaccinate their children. Efforts to increase awareness about vaccine safety and education about the importance of vaccinating children are needed.

COVID-19 testing among children, parental preferences for testing venues and acceptability of school-based testing: a survey of US parents (preprint)

In a national survey of 2,074 US parents conducted in March 2021, 35.9% reported their youngest child had been tested at least once for COVID-19. Parents preferred testing venue choice was the pediatricians office. Only half of parent surveyed (50.6%) reported that they would allow their child to be tested for COVID-19 at school/daycare if it was required.

Determinants of COVID-19 vaccine hesitancy and vaccine uptake in a national cohort of U.S. adults (preprint)

We estimated the trends and correlates of vaccine hesitancy, and its association with subsequent vaccine uptake among 5,458 adults in the United States. Participants belonged to the CHASING COVID Cohort, a national longitudinal study. Trends and correlates of vaccine hesitancy were examined longitudinally in eight interview rounds from October 2020 to July 2021. We also estimated the association between willingness to vaccinate and subsequent vaccine uptake through July 2021. Vaccine delay and refusal decreased from 51% and 8% in October 2020 to 8% and 6% in July 2021, respectively. Compared to Non-Hispanic (NH) White participants, NH Black and Hispanic participants had higher adjusted odds ratios (aOR) for both vaccine delay (aOR: 2.0 [95% CI: 1.5, 2.7] for NH Black and 1.3 [95% CI: 1.0, 1.7] for Hispanic) and vaccine refusal (aOR: 2.5 [95% CI: 1.8, 3.6] for NH Black and 1.4 [95% CI: 1.0, 2.0] for Hispanic) in June 2021. COVID-19 vaccine hesitancy was associated with lower odds of subsequent vaccine uptake (aOR: 0.15, 95% CI: 0.13, 0.18 for vaccine-delayers and aOR: 0.02; 95% CI: 0.01, 0.03 for vaccine-refusers compared to vaccine-willing participants), adjusted for sociodemographic factors and COVID-19 history. Vaccination awareness and distribution efforts should focus on vaccine delayers.

Plans to vaccinate children for COVID-19: a survey of US parents (preprint)

In a national online survey of 2,074 US parents conducted in March 2021, 49.4% reported plans to vaccinate their child for COVID-19 when available. Lower income and less education were associated with greater parental vaccine hesitancy/resistance, while safety, effectiveness and lack of need were the primary reasons for vaccine hesitancy/resistance.

Risk Profile of Thanksgiving Gatherers and Subsequent SARS-CoV2 Testing and Diagnosis (preprint)

ABSTRACT Background During Fall 2020 in the United States (U.S.), despite high COVID-19 case numbers and recommendations from public health officials not to travel and gather with individuals outside one’s household, millions of people gathered for Thanksgiving. The objective of this study was to understand if individuals’ behaviors and risk perceptions influenced their decision to gather, and if they did gather, their subsequent test seeking and diagnoses. Methods Participants were part of the CHASING COVID Cohort study - a U.S. national prospective cohort. The study sample consisted of participants who completed routine questionnaires before and after Thanksgiving. Non-pharmaceutical interventions (NPIs) use informed behavioral risk scores and a score of perceived risk of COVID-19 were assigned to each participant. Multinomial logistic regression models were used to assess the association between higher risk behaviors and gathering with other households, and the association of gathering with subsequent testing and test positivity. Results A total of 1,932 (40.5%) cohort participants spent Thanksgiving with individuals from at least one other household. Participants with higher behavioral risk scores had greater odds of gathering with one other household (aOR: 2.35, 95% CI: 2.0, 2.7), two other households (aOR: 4.54, 95% CI: 3.7, 5.6), and three or more other households (aOR: 5.44, 95% CI: 4.1, 7.2). Participants perceiving COVID-19 as a low-risk to themselves and others had greater odds of gathering with one other household (aOR: 1.12, 95% CI: 0.97, 1.3), two other households (aOR: 1.39, 95% CI: 1.1, 1.7), and three or more other households (aOR: 1.86, 95% CI: 1.4, 2.4). Those who spent Thanksgiving with one or more other households had 1.23 times greater odds (95% CI: 1.1, 1.4) of having a COVID-19 test afterward. There was no association between gathering for Thanksgiving and subsequent COVID-19 test positivity or developing COVID-19 symptoms. Conclusions Those who gathered with other households for Thanksgiving tended to engage in higher-risk activities. Thanksgiving gathering with other households was not associated with subsequently testing positive for COVID-19, but only a small proportion obtained post-travel testing. Public health messaging should emphasize behavior change strategies that promote safer gathering.

The emergence, surge and subsequent wave of the SARS-CoV-2 pandemic in New York metropolitan area: The view from a major region-wide urgent care provider. (preprint)

Background: Describing SARS-CoV-2 testing and positivity trends among urgent care users is crucial for understanding the trajectory of the pandemic. Objective: To describe demographic and clinical characteristics, positivity rates, and repeat testing patterns among patients tested for SARS-CoV-2 at CityMD, an urgent care provider in the New York City metropolitan area. Design: Retrospective study of all persons testing for SARS-CoV-2 between March 1, 2020 and January 8, 2021 at 115 CityMD locations in the New York metropolitan area. Patients: Individuals receiving a SARS-CoV-2 diagnostic or serologic test. Measurements: Test and individual level SARS-CoV-2 positivity by PCR, rapid antigen, or serologic tests. Results: During the study period, 3.4 million COVID tests were performed on 1.8 million individuals. In New York City, CityMD diagnosed 268,298 individuals, including 17% of all reported cases. Testing levels were higher among 20-29 year olds, non-Hispanic Whites, and females compared with other groups. About 24.8% (n=464,902) were repeat testers. Test positivity was higher in non-Hispanic Black (6.4%), Hispanic (8.0%), and Native American (8.0%) patients compared to non-Hispanic White (5.4%) patients. Overall seropositivity was estimated to be 21.7% (95% Confidence Interval [CI]: 21.6-21.8) and was highest among 10-14 year olds (27.3%). Seropositivity was also high among non-Hispanic Black (24.5%) and Hispanic (30.6%) testers, and residents of the Bronx (31.3%) and Queens (30.5%). Using PCR as the gold standard, SARS-CoV-2 rapid tests had a false positive rate of 5.4% (95%CI 5.3-5.5). Conclusion: Urgent care centers can provide broad access to critical evaluation, diagnostic testing and treatment of a substantial number of ambulatory patients during pandemics, especially in population-dense, urban epicenters.

Spread and sources of information and misinformation about COVID-19 early during the pandemic in a U.S. national cohort study (preprint)

Background: Early in the pandemic, misinformation about COVID-19 was spread on social media. The purpose of this study was to describe trusted sources of COVID-19 information and claims seen and believed about COVID-19 early in the pandemic among U.S. adults. Then, we assessed the impact of believing such claims on engaging in personal protective actions (PPA). Methods: We used baseline data from the CHASING COVID Cohort (n = 7,070) collected March 28, 2020 to April 20, 2020 to describe trusted sources of COVID-19 information as well as claims circulating on social media that had been seen and believed. We used Poisson regression to determine the association of believing certain claims with engaging in a higher number of PPA. Results: The top three trusted sources of COVID-19 information were the CDC (67.9%), the WHO (53.7%), and State Health Departments (53.0%). Several COVID-19 claims circulated on social media had been seen, e.g., that the virus was created in a laboratory (54.8%). Moreover, substantial proportions of participants indicated agreement with some of these claims. In multivariable regression, we found that belief in certain claims was associated with engaging in a higher number of PPA. For example, believing that paper masks would prevent transmission of the virus was associated with engaging in a higher number of protective actions ({beta} = 0.02, 95% CI: 0.004 - 0.046). Conclusions: Results suggest the need for public health leadership on social media platforms to combat misinformation and supports social media as a tool to further public health interventions.

Racial and ethnic differences in COVID-19 vaccine hesitancy and uptake (preprint)

Background Racial and ethnic minorities have been disproportionately impacted by COVID-19. In the initial phase of population-based vaccination in the United States (U.S.) and United Kingdom (U.K.), vaccine hesitancy and limited access may result in disparities in uptake. Methods We performed a cohort study among U.S. and U.K. participants in the smartphone-based COVID Symptom Study (March 24, 2020-February 16, 2021). We used logistic regression to estimate odds ratios (ORs) of COVID-19 vaccine hesitancy (unsure/not willing) and receipt. Results In the U.S. ( n =87,388), compared to White non-Hispanic participants, the multivariable ORs of vaccine hesitancy were 3.15 (95% CI: 2.86 to 3.47) for Black participants, 1.42 (1.28 to 1.58) for Hispanic participants, 1.34 (1.18 to 1.52) for Asian participants, and 2.02 (1.70 to 2.39) for participants reporting more than one race/other. In the U.K. ( n =1,254,294), racial and ethnic minorities had similarly elevated hesitancy: compared to White participants, their corresponding ORs were 2.84 (95% CI: 2.69 to 2.99) for Black participants, 1.66 (1.57 to 1.76) for South Asian participants, 1.84 (1.70 to 1.98) for Middle East/East Asian participants, and 1.48 (1.39 to 1.57) for participants reporting more than one race/other. Among U.S. participants, the OR of vaccine receipt was 0.71 (0.64 to 0.79) for Black participants, a disparity that persisted among individuals who specifically endorsed a willingness to obtain a vaccine. In contrast, disparities in uptake were not observed in the U.K. Conclusions COVID-19 vaccine hesitancy was greater among racial and ethnic minorities, and Black participants living in the U.S. were less likely to receive a vaccine than White participants. Lower uptake among Black participants in the U.S. during the initial vaccine rollout is attributable to both hesitancy and disparities in access.

Recent SARS-CoV-2 seroconversion in a national, community-based prospective cohort of U.S. adults (preprint)

SHORT ABSTRACTEpidemiologic risk factors for incident SARS-CoV-2 infection are best characterized via prospective cohort studies, complementing case-based surveillance and cross-sectional seroprevalence studies. In March 2020, we launched the CHASING COVID Cohort Study, a national, community-based prospective cohort study of 6,745 U.S. adults who underwent at-home specimen collection for repeat serologic testing for SARS-CoV-2 antibodies. We identify and quantify several policy-sensitive risk factors for recent SARS-CoV-2 seroconversion, highlight persistent racial/ethnic disparities in incidence, document continued elevated risk among essential workers, and call attention to major gaps in the coverage of public health interventions aimed at testing, isolation, and contact tracing. We conclude that modifiable risk factors and poor reach of public health strategies drive SARS-CoV-2 transmission and inequities across the U.S.