Factors associated with COVID-19 vaccination during June-October 2021: A multi-site prospective study.

INTRODUCTION: Vaccine hesitancy presents a challenge to COVID-19 control efforts. To identify beliefs associated with delayed vaccine uptake, we developed and implemented a vaccine hesitancy survey for the COVID-19 Community Research Partnership. METHODS: In June 2021, we assessed attitudes and beliefs associated with COVID-19 vaccination using an online survey. Self-reported vaccination data were requested daily through October 2021. We compared responses between vaccinated and unvaccinated respondents using absolute standardized mean differences (ASMD). We assessed validity and reliability using exploratory factor analysis and identified latent factors associated with a subset of survey items. Cox proportional hazards models and mediation analyses assessed predictors of subsequent vaccination among those initially unvaccinated. RESULTS: In June 2021, 29,522 vaccinated and 1,272 unvaccinated participants completed surveys. Among those unvaccinated in June 2021, 559 (43.9 %) became vaccinated by October 31, 2021. In June, unvaccinated participants were less likely to feel "very concerned" about getting COVID-19 than vaccinated participants (10.6 % vs. 43.3 %, ASMD 0.792). Among those initially unvaccinated, greater intent to become vaccinated was associated with getting vaccinated and shorter time to vaccination. However, even among participants who reported no intention to become vaccinated, 28.5 % reported vaccination before study end. Two latent factors predicted subsequent vaccination-being 'more receptive' was derived from motivation to protect one's own or others' health and resume usual activities; being 'less receptive' was derived from concerns about COVID-19 vaccines. In a Cox model, both factors were partially mediated by vaccination intention. CONCLUSION: This study characterizes vaccine hesitant individuals and identifies predictors of eventual COVID-19 vaccination through October 31, 2021. Even individuals with no intention to be vaccinated can shift to vaccine uptake. Our data suggest factors of perceived severity of COVID-19 disease, vaccine safety, and trust in the vaccine development process are predictive of vaccination and may be important opportunities for ongoing interventions.

Persistence of antibody responses to COVID-19 vaccines among participants in the COVID-19 Community Research Partnership.

Introduction: High levels of immunity to SARS-CoV-2 in the community correlate with protection from COVID-19 illness. Measuring COVID-19 antibody seroprevalence and persistence may elucidate the level and length of protection afforded by vaccination and infection within a population. Methods: We measured the duration of detectable anti-spike antibodies following COVID-19 vaccination in a multistate, longitudinal cohort study of almost 13,000 adults who completed daily surveys and submitted monthly dried blood spots collected at home. Results: Overall, anti-spike antibodies persisted up to 284 days of follow-up with seroreversion occurring in only 2.4% of the study population. In adjusted analyses, risk of seroreversion increased with age (adults aged 55-64: adjusted hazard ratio [aHR] 2.19 [95% confidence interval (CI): 1.22, 3.92] and adults aged > 65: aHR 3.59 [95% CI: 2.07, 6.20] compared to adults aged 18-39). Adults with diabetes had a higher risk of seroreversion versus nondiabetics (aHR 1.77 [95% CI: 1.29, 2.44]). Decreased risk of seroreversion was shown for non-Hispanic Black versus non-Hispanic White (aHR 0.32 [95% CI: 0.13, 0.79]); college degree earners versus no college degree (aHR 0.61 [95% CI: 0.46, 0.81]); and those who received Moderna mRNA-1273 vaccine versus Pfizer-BioNTech BNT162b2 (aHR 0.35 [95% CI: 0.26, 0.47]). An interaction between healthcare worker occupation and sex was detected, with seroreversion increased among male, non-healthcare workers. Conclusion: We established that a remote, longitudinal, multi-site study can reliably detect antibody durability following COVID-19 vaccination. The survey platform and measurement of antibody response using at-home collection at convenient intervals allowed us to explore sociodemographic factors and comorbidities and identify predictors of antibody persistence, which has been demonstrated to correlate with protection against disease. Our findings may help inform public health interventions and policies to protect those at highest risk for severe illness and assist in determining the optimal timing of booster doses.Clinical trials registry: NCT04342884.

Self-Reported SARS-CoV-2 Vaccination Is Consistent with Electronic Health Record Data among the COVID-19 Community Research Partnership.

Introduction: Observational studies of SARS-CoV-2 vaccine effectiveness depend on accurate ascertainment of vaccination receipt, date, and product type. Self-reported vaccine data may be more readily available to and less expensive for researchers than assessing medical records. Methods: We surveyed adult participants in the COVID-19 Community Research Partnership who had an authenticated Electronic Health Record (EHR) (N = 41,484) concerning receipt of SARS-CoV-2 vaccination using a daily survey beginning in December 2020 and a supplemental survey in September-October 2021. We compared self-reported information to that available in the EHR for the following data points: vaccine brand, date of first dose, and number of doses using rates of agreement and Bland-Altman plots for visual assessment. Self-reported data was available immediately following vaccination (in the daily survey) and at a delayed interval (in a secondary supplemental survey). Results: For the date of first vaccine dose, self-reported "immediate" recall was within ±7 days of the date reported in the "delayed" survey for 87.9% of participants. Among the 19.6% of participants with evidence of vaccination in their EHR, 95% self-reported vaccination in one of the two surveys. Self-reported dates were within ±7 days of documented EHR vaccination for 97.6% of the "immediate" surveys and 92.0% of the "delayed" surveys. Self-reported vaccine product details matched those in the EHR for over 98% of participants for both "immediate" and "delayed" surveys. Conclusions: Self-reported dates and product details for COVID-19 vaccination can be a good surrogate when medical records are unavailable in large observational studies. A secondary confirmation of dates for a subset of participants with EHR data will provide internal validity.

Changing Attitudes toward the COVID-19 Vaccine among North Carolina Participants in the COVID-19 Community Research Partnership.

Coronavirus Disease-2019 (COVID-19) vaccine acceptance is variable. We surveyed participants in the COVID-19 Community Research Partnership from 17 December 2020 to 13 January 2021 to assess vaccine receptiveness. Vaccine uptake was then monitored until 15 May 2021; 20,232 participants responded to the receptiveness survey with vaccination status accessed in 18,874 participants via daily follow-up surveys (participants not completing daily surveys ≥30 days to 15 May 2021, were excluded). In the initial survey, 4802 (23.8%) were vaccine hesitant. Hesitancy was most apparent in women (Adjusted RR 0.93, p < 0.001), Black Americans (Adjusted RR 1.39, 1.41, 1.31 to non-Hispanic Whites, Other, and Hispanic or Latino, respectively p < 0.001), healthcare workers (Adjusted RR 0.93, p < 0.001), suburbanites (ref. Urban Adjusted RR 0.85, 0.90 to urban and rural dwellers, respectively, p < 0.01), and those previously diagnosed with COVID-19 (RR 1.20, p < 0.01). Those <50 years were also less accepting of vaccination. Subsequent vaccine uptake was 99% in non-hesitant participants. For those who were unsure, preferred not to answer, or answered "no", vaccination rates were 80% (Adjusted RR 0.86, p < 0.0001), 78% (Adjusted RR 0.83, p < 0.0001), and 52.7% (Adjusted RR 0.65, p < 0.0001), respectively. These findings suggest that initial intent did not correlate with vaccine uptake in our cohort.