William You

Within the USA, the uptake of the updated COVID-19 vaccines is suboptimal despite health authority recommendations. This study used qualitative methods to examine factors influencing COVID-19 vaccine decision making and the effects of anxiety and depression on these decisions within the CHASING COVID Cohort (C3). Between October and December 2023, we conducted 25 interviews with participants from 16 different US states, 14 of whom endorsed recent symptoms of anxiety and/or depression. Using grounded theory methodology for coding and thematic analysis, we categorized participants into “One-Shot Wonders” and “Booster Enthusiasts”. Our findings indicate that the US COVID-19 vaccination environment has shifted from active promotion to a notable absence of COVID-19 discussions, leading to reduced worry about infection and severe illness, diminished perception of the benefits of the vaccine on personal and community levels, and fewer cues to action. Initially influential factors like family, personal experiences, and physician recommendations lost impact over time. Although the relationship between symptoms of depression and anxiety and vaccination was not prominent, one case highlighted a direct relationship. The study emphasizes the importance of timely and accurate public health messaging adaptable to individuals’ needs and misconceptions, highlighting the need for dynamic communication strategies in future initiatives with rapidly changing landscapes.

It is crucial to understand factors associated with COVID-19 booster uptake in the United States given the updated COVID-19 vaccine recommendations. Using data from a national prospective cohort (n = 4616) between September 2021 and October 2022, we examined socioeconomic, demographic, and behavioral factors of initial booster uptake among participants fully vaccinated with the primary COVID-19 vaccines series. Cox proportional hazards models were used to estimate the associations of each factor with time to initial booster uptake. Most participants (86.5%) reported receiving their initial booster. After adjusting for age, race/ethnicity, education, region, and employment, participants with greater risk for severe COVID-19 had similar booster uptake compared with those with lower risk (adjusted hazard ratio [aHR], 1.04; 95% CI, 0.95-1.14). Participants with greater barriers to healthcare (aHR, 0.89; 95% CI, 0.84-0.96), food insecurity (aHR, 0.82; 95% CI, 0.75-0.89), and housing instability (aHR, 0.81; 95% CI, 0.73-0.90) were less likely to report receiving initial booster compared with those without those barriers. Factors motivating the decision to vaccinate changed from safety-related concerns for the primary series to perceived need for the booster. It is key to address economic and health access barriers to achieve equitable COVID-19 vaccine uptake and continued protection against COVID-19.

LONG 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: aIRR _{un/undervaccinated} =5.3 (95% CI: 4.2-6.7); aIRR _{primary series only} =5.1 (95% CI: 4.2-7.3); aIRR _{boosted once} =2.5 (95% CI: 2.1-3.0), and aIRR _{boosted 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. SHORT This study used repeat serologic testing to estimate infection rates and risk factors in two overlapping cohorts of SARS-CoV-2 N protein seronegative U.S. adults. One mostly unvaccinated sub-cohort was tracked from April to November 2020 (pre-vaccine/wild-type era, n=3,421), and the other, mostly vaccinated cohort, from November 2020 to June 2022 (vaccine/variant era, n=2,735). Vaccine uptake was from 0.53% and 91.3% in the pre-vaccine and vaccine/variant cohorts, respectively. Corresponding seroconversion rates were 9.6 and 25.7 per 100 person-years. In both cohorts, sociodemographic and epidemiologic risk factors for infection were similar, though new risks emerged in the vaccine/variant era, such as having a child in the household. Despite higher incidence rates in the vaccine/variant cohort, vaccine boosters, masking, and distancing likely reduced infection risk, even through major variant surges. Repeat serologic testing in cohorts is a useful and complementary strategy to characterize incidence and risk factors. Funding: The work was supported by the CUNY Institute for Implementation Science in Population Health, the U.S. National Institutes of Allergy and Infectious Diseases (NIAID), Pfizer, Inc., and the U.S. National Institute of Mental Health (NIMH).

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, parents’ vaccination status was associated with higher likelihood of children’s vaccine uptake (age-specific adjusted odds ratios [aORs]: aOR _16-17 3.7, 95% CI 2.3, 5.9, aOR _12-15 3.7, 95% CI 2.6, 5.3; aOR _5-11 10.6, 95% CI 5.4, 20.9). Parents’ education (aOR _16-17 1.4, 95% CI 1.1, 1.8, aOR _12-15 1.5, 95% CI 1.2, 1.9; aOR _5-11 2.1, 95% CI 1.5, 2.9) and worry about others getting infected (aOR _5-11 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.

Background: Inadequate screening and diagnostic testing in the United States throughout the first several months of the COVID-19 pandemic led to undetected cases transmitting disease in the community and an underestimation of cases. Though testing supply has increased, maintaining testing uptake remains a public health priority in the efforts to control community transmission considering the availability of vaccinations and threats from variants. Objective: This study aimed to identify patterns of preferences for SARS-CoV-2 screening and diagnostic testing prior to widespread vaccine availability and uptake. Methods: We conducted a discrete choice experiment (DCE) among participants in the national, prospective CHASING COVID (Communities, Households, and SARS-CoV-2 Epidemiology) Cohort Study from July 30 to September 8, 2020. The DCE elicited preferences for SARS-CoV-2 test type, specimen type, testing venue, and result turnaround time. We used latent class multinomial logit to identify distinct patterns of preferences related to testing as measured by attribute-level part-worth utilities and conducted a simulation based on the utility estimates to predict testing uptake if additional testing scenarios were offered. Results: Of the 5098 invited cohort participants, 4793 (94.0%) completed the DCE. Five distinct patterns of SARS-CoV-2 testing emerged. Noninvasive home testers (n=920, 19.2% of participants) were most influenced by specimen type and favored less invasive specimen collection methods, with saliva being most preferred; this group was the least likely to opt out of testing. Fast-track testers (n=1235, 25.8%) were most influenced by result turnaround time and favored immediate and same-day turnaround time. Among dual testers (n=889, 18.5%), test type was the most important attribute, and preference was given to both antibody and viral tests. Noninvasive dual testers (n=1578, 32.9%) were most strongly influenced by specimen type and test type, preferring saliva and cheek swab specimens and both antibody and viral tests. Among hesitant home testers (n=171, 3.6%), the venue was the most important attribute; notably, this group was the most likely to opt out of testing. In addition to variability in preferences for testing features, heterogeneity was observed in the distribution of certain demographic characteristics (age, race/ethnicity, education, and employment), history of SARS-CoV-2 testing, COVID-19 diagnosis, and concern about the pandemic. Simulation models predicted that testing uptake would increase from 81.6% (with a status quo scenario of polymerase chain reaction by nasal swab in a provider’s office and a turnaround time of several days) to 98.1% by offering additional scenarios using less invasive specimens, both viral and antibody tests from a single specimen, faster turnaround time, and at-home testing. Conclusions: We identified substantial differences in preferences for SARS-CoV-2 testing and found that offering additional testing options would likely increase testing uptake in line with public health goals. Additional studies may be warranted to understand if preferences for testing have changed since the availability and widespread uptake of vaccines.

BACKGROUND Inadequate screening and diagnostic testing in the United States throughout the first several months of the COVID-19 pandemic led to undetected cases transmitting disease in the community and an underestimation of cases. Though testing supply has increased, maintaining testing uptake remains a public health priority in the efforts to control community transmission considering the availability of vaccinations and threats from variants. OBJECTIVE This study aimed to identify patterns of preferences for SARS-CoV-2 screening and diagnostic testing prior to widespread vaccine availability and uptake. METHODS We conducted a discrete choice experiment (DCE) among participants in the national, prospective CHASING COVID (Communities, Households, and SARS-CoV-2 Epidemiology) Cohort Study from July 30 to September 8, 2020. The DCE elicited preferences for SARS-CoV-2 test type, specimen type, testing venue, and result turnaround time. We used latent class multinomial logit to identify distinct patterns of preferences related to testing as measured by attribute-level part-worth utilities and conducted a simulation based on the utility estimates to predict testing uptake if additional testing scenarios were offered. RESULTS Of the 5098 invited cohort participants, 4793 (94.0%) completed the DCE. Five distinct patterns of SARS-CoV-2 testing emerged. Noninvasive home testers (n=920, 19.2% of participants) were most influenced by specimen type and favored less invasive specimen collection methods, with saliva being most preferred; this group was the least likely to opt out of testing. Fast-track testers (n=1235, 25.8%) were most influenced by result turnaround time and favored immediate and same-day turnaround time. Among dual testers (n=889, 18.5%), test type was the most important attribute, and preference was given to both antibody and viral tests. Noninvasive dual testers (n=1578, 32.9%) were most strongly influenced by specimen type and test type, preferring saliva and cheek swab specimens and both antibody and viral tests. Among hesitant home testers (n=171, 3.6%), the venue was the most important attribute; notably, this group was the most likely to opt out of testing. In addition to variability in preferences for testing features, heterogeneity was observed in the distribution of certain demographic characteristics (age, race/ethnicity, education, and employment), history of SARS-CoV-2 testing, COVID-19 diagnosis, and concern about the pandemic. Simulation models predicted that testing uptake would increase from 81.6% (with a status quo scenario of polymerase chain reaction by nasal swab in a provider’s office and a turnaround time of several days) to 98.1% by offering additional scenarios using less invasive specimens, both viral and antibody tests from a single specimen, faster turnaround time, and at-home testing. CONCLUSIONS We identified substantial differences in preferences for SARS-CoV-2 testing and found that offering additional testing options would likely increase testing uptake in line with public health goals. Additional studies may be warranted to understand if preferences for testing have changed since the availability and widespread uptake of vaccines.

Background Vaccine hesitancy in the U.S. may limit the potential to alleviate the public health threat caused by the COVID-19 pandemic. Methods We estimated trends in and correlates of vaccine hesitancy, and its association with subsequent vaccine uptake among 5,085 United States adults from the CHASING COVID Cohort study, a national longitudinal study. Trends in willingness to vaccinate were examined longitudinally in three rounds of interviews from September to December 2020. We assessed correlates of willingness to vaccinate in December 2020. We also estimated the association between willingness to vaccinate in December 2020 and subsequent vaccine uptake in February 2021. Results Vaccine hesitancy and resistance decreased from 51% and 8% in September 2020 to 35% and 5% in December 2020, respectively. Compared to Non-Hispanic (NH) White participants, NH Black and Hispanic participants had higher adjusted odds ratios (aOR) for both vaccine hesitancy (aOR: 3.3 [95% CI: 2.6, 4.2] for NH Black and 1.8 [95% CI: 1.5, 2.2] for Hispanic) and vaccine resistance (aOR: 6.4 [95% CI: 4.3, 9.4] for NH Black and 1.9 [95% CI: 1.3, 2.7] for Hispanic). Willingness to vaccinate was associated with lower odds of vaccine uptake among 65+ year olds (aOR: 0.4, 95% CI: 0.3, 0.6 for hesitancy; aOR: 0.1, 95% CI: 0.01, 0.6 for resistance) and healthcare workers (aOR: 0.2, 95% CI: 0.1, 0.3 for hesitancy; aOR: 0.04, 95% CI: 0.006, 0.2 for resistance). Conclusions Awareness and distribution efforts should focus on vaccine hesitant vulnerable populations.

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.

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 (β = 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.