SARS-CoV-2 serosurvey across multiple waves of the COVID-19 pandemic in New York City between 2020-2023.

Sero-monitoring provides context to the epidemiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections and changes in population immunity following vaccine introduction. Here, we describe results of a cross-sectional hospital-based study of anti-spike seroprevalence in New York City (NYC) from February 2020 to July 2022, and a follow-up period from August 2023 to October 2023. Samples from 55,092 individuals, spanning five epidemiological waves were analyzed. Prevalence ratios (PR) were obtained using Poisson regression. Anti-spike antibody levels increased gradually over the first two waves, with a sharp increase during the 3rd wave coinciding with SARS-CoV-2 vaccination in NYC resulting in seroprevalence levels >90% by July 2022. Our data provide insights into the dynamic changes in immunity occurring in a large and diverse metropolitan community faced with a new viral pathogen and reflects the patterns of antibody responses as the pandemic transitions into an endemic stage.

A systematic review and meta-analysis of herpes zoster occurrence/recurrence after COVID-19 infection and vaccination.

To inform surveillance, prevention, and management strategies for the varicella zoster virus (VZV) during the COVID-19 pandemic, this study aimed to evaluate the risk of herpes zoster (HZ) occurrence/recurrence following COVID-19 infection and vaccination. A comprehensive search across seven databases was conducted up to January 31, 2024, to identify studies relevant to the occurrence of HZ following COVID-19 infection and vaccination. The meta-analysis included five studies on postinfection HZ and 13 studies on postvaccination HZ. Patients infected with COVID-19 had a 2.16-fold increased risk of HZ (95% confidence interval [CI]: 1.24-3.76) than uninfected individuals. However, there was no significant association between COVID-19 vaccination and the risk of HZ compared to controls, with a relative risk (RR) of 1.08 (95% CI: 0.84-1.39). Furthermore, a descriptive analysis of 74 postinfection and 153 postvaccination HZ studies found no significant differences on gender or age (<50 and ≥50 years) following COVID-19 infection. Notably, 44.0% of the HZ cases postinfection appeared within the first week, with 69.5% resolving within 10 days, predominantly presenting as skin lesions. In the postvaccination group, the majority (60.1%) developed HZ after the first dose and 66.7% occurred within 1 week. Moreover, 44.6% resolved within 10 days and 50.0% within a month, primarily exhibiting skin lesions and postherpetic neuralgia. The study found that COVID-19 infection increases the risk of HZ, but the COVID-19 vaccine does not. Further study is needed to explore the association between COVID-19 and HZ.

Complex interplay of science reasoning and vaccine hesitancy among parents in Shanghai, China.

The psychosocial underpinnings of vaccine hesitancy are complex. Research is needed to pinpoint the exact reasons why people hesitate to vaccinate themselves or their children against vaccine-preventable diseases. One possible reason are concerns that arise from a misunderstanding of vaccine science. We examined the impact of scientific reasoning on vaccine hesitancy and human papillomavirus (HPV) vaccination intent through a cross-sectional study of parents of vaccine-eligible children (N = 399) at immunization clinics in Shanghai, China. We assessed the relationship between science reasoning and both vaccine hesitancy and HPV vaccine acceptance using general additive models. We found a significant association between scientific reasoning and education level, with those with less than a high school education having a significantly lower scientific reasoning that those with a college education (ß = -1.31, p-value = 0.002). However, there was little evidence of a relationship between scientific reasoning and vaccine hesitancy. Scientific reasoning therefore appears not to exert primary influence on the formation of vaccine attitudes among the respondents surveyed. We suggest that research on vaccine hesitancy continues working to identify the styles of reasoning parents engage in when determining whether or not to vaccinate their children. This research could inform the development and implementation of tailored vaccination campaigns.

Parental vaccine hesitancy and acceptance of a COVID-19 vaccine: An internet-based survey in the US and five Asian countries.

COVID-19 vaccination rates for children globally are relatively low. This study aimed to investigate parental vaccine hesitancy and parents' acceptance of a COVID-19 for their children for their children in the United States, China, Taiwan, India, Indonesia, and Malaysia.We analyzed data from an opt-in, internet-based cross-sectional study (n = 23,940). Parents were asked about their acceptance of a COVID-19 vaccine for their children, and if they would accept the vaccine with different risk and effectiveness profiles for themselves. Poisson regression was used to generate prevalence ratios (PR) of the relationship between vaccine acceptance for a child and vaccine profile, by country and waves and overall. Between August 2020 and June 2021, COVID-19 vaccine acceptance for children decreased in the United States (89% to 72%) and Taiwan (79% to 71%), increased in India (91% to 96%) and Malaysia (81% to 91%), and was stable in Indonesia (86%) and China (at 87%-90%). Vaccine risk and effectiveness profiles did not consistently affect parent's acceptance of a COVID-19 vaccine for their children. Instead, being not hesitant was a large driver of vaccine acceptance (PR: 1.24, 95% CI: 1.14, 1.36). Adolescent COVID-19 vaccination have already been established in many high and middle-income countries, but our study suggests that there is a movement of vaccine hesitancy which could impede the success of future pediatric and adolescent COVID-19 vaccination programs.

Trends in childhood vaccination in Pakistan and associated factors; 2006-2018.

INTRODUCTION: Pakistan still has ongoing transmission of wild type polio virus. This study aims to determine changes in full vaccination with recommended Expanded Program on Immunization vaccines, including polio, by several socio-economic and demographic factors. METHODS: We used three waves of Pakistan's Demographic and Health Survey, a population-based cross-sectional study from 2006-07 (N = 1471), 2012-13 (N = 1706), and 2017-18 (N = 1549), analyzed by residence, wealth, and sociodemographic factors. Analysis was limited to children aged 12-23 months in Punjab, Sindh, Northwest Frontier Province/Khyber Pakhtunkhwa and Balochistan. Full vaccination was measured as receipt of one Bacillus Calmette-Guérin dose, one measles dose, 3 polio doses, and 3 Diphtheria-Tetanus-Pertussis doses. Odds ratios (ORs) and 95 % confidence intervals (CIs) from logistic regression were used to determine associations between undervaccination and demographic variables. RESULTS: Full vaccination coverage was 50.6 % in 2006-07, 54.7 % in 2012-13, and 68.3 % in 2017-18. In 2006-07, the odds of undervaccination were significantly higher in Sindh (OR: 1.74, 95 % CI: 1.30, 2.31) than Punjab, and disparities across province changed over time (P < 0.0001); notably, undervaccination was significantly higher in Sindh, KPK, and Balochistan than Punjab in 2017. Compared to the middle wealth quintile, the poorest had significantly higher odds of undervaccination in 2006-07 (OR: 2.58, 95 % CI: 1.76, 3.78), and this did not significantly change over time (P = 0.2168). The proportion of those with a polio birth dose increased across waves from 56.3 % in 2006-07 to 83.7 % in 2017-18; receiving three or more polio vaccine doses remained unchanged. CONCLUSION: This study showed that the proportion of fully vaccinated children in Pakistan increased across three waves. Full vaccination and administration of polio vaccine birth doses have increased recently in Pakistan. The association between undervaccination with province differed significantly across the waves, with vaccination disparities between provinces increasing. Those in the poorest wealth quintile had the greatest odds of undervaccination.

Mapping the Cognitive Biases Related to Vaccination: A Scoping Review of the Literature.

INTRODUCTION: Human behavior and understanding of the vaccine ecosystem play a critical role in the vaccination decision-making process. The objective of this study was to understand different cognitive biases that may lead to vaccine acceptance or hesitancy. METHODS: The eligibility criteria for this scoping review was vaccination-related cognitive bias studies published in the English language from inception to April 2022 and available on PubMed, Embase, and Google Scholar. It included all geographical locations and individuals of all age groups and excluded studies focusing on (i) clinical trials of vaccines, (ii) vaccine research conduct bias, (iii) cognitive delay, or (iv) statistical biases. The search method also included reviewing references in the retrieved articles. RESULTS: Overall, 58 articles were identified, and after screening, 19 were included in this study. Twenty-one cognitive biases with the potential to affect vaccination decision-making were observed. These biases were further grouped into three broad categories: cognitive biases seen while processing vaccine-related information, during vaccination-related decision-making, and due to prior beliefs regarding vaccination. CONCLUSIONS: This review identified critical cognitive biases affecting the entire process of vaccination that can influence research and public health efforts both positively and negatively. Recognizing and mitigating these cognitive biases is crucial for maintaining the population's level of trust in vaccination programs around the world.

Design and analysis heterogeneity in observational studies of COVID-19 booster effectiveness: A review and case study.

We investigated the design and analysis of observational booster vaccine effectiveness (VE) studies by performing a scoping review of booster VE literature with a focus on study design and analytic choices. We then applied 20 different approaches, including those found in the literature, to a single dataset from Michigan Medicine. We identified 80 studies in our review, including over 150 million observations in total. We found that while protection against infection is variable and dependent on several factors including the study population and time period, both monovalent boosters and particularly the bivalent booster offer strong protection against severe COVID-19. In addition, VE analyses with a severe disease outcome (hospitalization, intensive care unit admission, or death) appear to be more robust to design and analytic choices than an infection endpoint. In terms of design choices, we found that test-negative designs and their variants may offer advantages in statistical efficiency compared to cohort designs.

Public willingness to receive chlamydia, gonorrhea, syphilis, and trichomoniasis vaccines: a scoping review.

BACKGROUND: Sexually transmitted infections (STIs) like chlamydia, gonorrhea, syphilis, and trichomoniasis contribute significantly to global morbidity and mortality. Researchers are pursuing vaccines for these STIs, and a clinical trial is currently underway for a chlamydia vaccine. However, there is little research available on individuals' willingness to receive chlamydia, gonorrhea, syphilis, and trichomoniasis vaccines. The purpose of this analysis was to map the existing literature we have on individuals' willingness to receive these bacterial/parasitic STI vaccines and understand what information on vaccine acceptability is still needed. METHODS: We searched seven databases for literature on STI vaccine acceptability, then conducted title/abstract and full-text reviews to assess eligibility. All reviews and abstractions were conducted blindly by two reviewers, with discrepancies settled by discussion or the input of a third reviewer. RESULTS: Eight of the original 2,259 texts of interest met inclusion criteria. After data abstraction, we found that gonorrhea was the most commonly examined, followed by chlamydia and syphilis. Trichomoniasis vaccine acceptability was not reported. Most texts reported high acceptability, but there did not appear to be data describing how vaccine characteristics affect acceptability. Similarly, while the literature covers a variety of populations, most of the study populations were based out of the United States or Canada and were patrons of healthcare facilities or participants from a larger health intervention study. Therefore, more information is needed on populations outside North America, and on groups with lower healthcare access and utilization. CONCLUSION: As the incidence of bacterial and parasitic STIs increase, and as we grow nearer vaccines for these illnesses, understanding how likely the public is to accept and receive these vaccines is crucial to their success. While the existing literature describes STI vaccine acceptability in a variety of populations, their overall number is small. More research into STI vaccine acceptability outside of North America, and especially examining how factors like number of doses, timing, and cost influence vaccine acceptability is needed to ensure effective future vaccine rollouts.

Maternally transmitted anti-measles antibodies, and susceptibility to disease among infants in Chandigarh, India: A prospective birth cohort study.

Prior to the age of measles vaccination, infants are believed to be protected against measles by passively transferred maternal antibodies. However, the quantity and quality of such protection have not been well established in the Indian setting. We undertook this study to characterize the transfer and decline in maternal anti-measles antibodies among infants, and determine their susceptibility to measles. In this population-based, birth-cohort study, we enrolled pregnant women and their newborn infants, from a catchment area of 30 Anganwadis in Chandigarh, India. We collected maternal blood at delivery, and infant blood samples at birth, and 3, 6, and 9 months of age. Anti-measles IgG antibodies were measured using quantitative ELISA. We assessed antibody decline using log-linear models. In total, 428 mother-infant dyads were enrolled, and data from 413 dyads were analyzed. At birth, 91.5% (95% CI: 88.8, 94.2) of infants had protective antibody levels, which declined to 26.3% (95% CI: 21.0%, 31.9) at 3 months, 3.4% (95% CI: 0.9, 5.9) at 6 months, and 2.1% (95% CI: 0.1, 4.1) at 9 months. Younger mothers transferred lower levels of antibodies to their infants. We concluded that the majority of infants are susceptible to measles as early as three months of age, much earlier than their eligibility to receive measles vaccination.

The impact of the COVID-19 pandemic on parental vaccine hesitancy: A cross-sectional survey.

BACKGROUND: It is unclear how hesitancy towards pediatric vaccines has changed quantitatively since the onset of the COVID-19 pandemic, and if changes are more readily apparent in clusters of low COVID-19 vaccination. In this study, we assess how clusters of low COVID-19 vaccination correlate with changing parental beliefs about childhood vaccines. METHODS: A cross-sectional, opt-in, internet-based survey of parents resident in the U.S. was conducted during August-September 2022. Our survey measured changes in beliefs about childhood vaccine safety, importance, and effectiveness since the start of COVID-19. We also measured parents' perceived vaccination rates in the community, assessing its relationship with changing vaccination perceptions using Rao-Scott chi-square tests, and multinomial logistic regression models. RESULTS: Among 310 parents of children 0-17 years old, 11 % (95 % CI: 7 %, 15 %) believed that childhood vaccines are less safe, 12 % (95 % CI: 8 %, 17 %) less important, and 13 % (95 % CI: 9 %, 18 %) less effective since the start of the COVID-19 pandemic. About 9 % (95 % CI: 5 %, 12 %) stated COVID-19 vaccination coverage was low in their community. Among those who stated COVID-19 vaccination coverage was low, 38 % reported believing childhood vaccines were less effective (vs 12 % of those who stated vaccination coverage was high). This corresponds to 4.34 times greater odds of believing childhood vaccines were less effective since the start of the pandemic (95 % CI: 1.38, 13.73) in those who believe COVID-19 vaccination coverage to be low in their community vs high. CONCLUSION: Our study demonstrates that parental perceptions about childhood vaccines have been affected by the COVID-19 pandemic through geographic and social clustering of non-vaccination. Beliefs about the COVID-19 vaccine have spillover with beliefs about childhood vaccines, and more negative beliefs may be clustering in areas with low vaccination coverage, which could predispose the area to outbreaks of vaccine-preventable disease.

COVID-19 vaccination preferences during a pause in Johnson & Johnson vaccine administration.

In April 2021, the US paused Janssen (J&J) COVID-19 vaccination because of reported blood clots post vaccination. This paper explores how vaccine decision-making--receiving a J&J vaccine right away vs waiting for a Pfizer vaccine--changed during the pause. In an opt-in internet-based survey April 2021 with 915 participants, 37 % were not vaccinated. Of these, 18 % would accept a J&J vaccine, 5 % would wait 1 month for a Pfizer vaccine, 25 % would wait 3 months, and 52 % would not want any vaccine. Among the unvaccinated, 56 % had heard of blood clots; 61 % of these did not want any vaccine, compared to 41 % of those who had not heard of blood clots. Moreover, among those vaccine hesitant in general, 11 % would still obtain a J&J vaccine if offered right away. These findings may suggest spillover of brand-specific adverse event concerns to the vaccine product as a whole.

Design and Analysis Heterogeneity in Observational Studies of COVID-19 Booster Effectiveness: A Review and Case Study.

Background: Observational vaccine effectiveness (VE) studies based on real-world data are a crucial supplement to initial randomized clinical trials of Coronavirus Disease 2019 (COVID-19) vaccines. However, there exists substantial heterogeneity in study designs and statistical methods for estimating VE. The impact of such heterogeneity on VE estimates is not clear. Methods: We conducted a two-step literature review of booster VE: a literature search for first or second monovalent boosters on January 1, 2023, and a rapid search for bivalent boosters on March 28, 2023. For each study identified, study design, methods, and VE estimates for infection, hospitalization, and/or death were extracted and summarized via forest plots. We then applied methods identified in the literature to a single dataset from Michigan Medicine (MM), providing a comparison of the impact of different statistical methodologies on the same dataset. Results: We identified 53 studies estimating VE of the first booster, 16 for the second booster. Of these studies, 2 were case-control, 17 were test-negative, and 50 were cohort studies. Together, they included nearly 130 million people worldwide. VE for all outcomes was very high (around 90%) in earlier studies (i.e., in 2021), but became attenuated and more heterogeneous over time (around 40%-50% for infection, 60%-90% for hospitalization, and 50%-90% for death). VE compared to the previous dose was lower for the second booster (10-30% for infection, 30-60% against hospitalization, and 50-90% against death). We also identified 11 bivalent booster studies including over 20 million people. Early studies of the bivalent booster showed increased effectiveness compared to the monovalent booster (VE around 50-80% for hospitalization and death).Our primary analysis with MM data using a cohort design included 186,495 individuals overall (including 153,811 boosted and 32,684 with only a primary series vaccination), and a secondary test-negative design included 65,992 individuals tested for SARS-CoV-2. When different statistical designs and methods were applied to MM data, VE estimates for hospitalization and death were robust to analytic choices, with test-negative designs leading to narrower confidence intervals. Adjusting either for the propensity of getting boosted or directly adjusting for covariates reduced the heterogeneity across VE estimates for the infection outcome. Conclusion: While the advantage of the second monovalent booster is not obvious from the literature review, the first monovalent booster and the bivalent booster appear to offer strong protection against severe COVID-19. Based on both the literature view and data analysis, VE analyses with a severe disease outcome (hospitalization, ICU admission, or death) appear to be more robust to design and analytic choices than an infection endpoint. Test-negative designs can extend to severe disease outcomes and may offer advantages in statistical efficiency when used properly.

Application of the double bounded dichotomous choice model to the estimation of parent's willingness to pay for the hand foot mouth disease vaccination: A survey in Selangor, Malaysia.

Hand foot and mouth disease (HFMD) is a notifiable viral disease in Malaysia, and is transmitted primarily among young children. Although vaccines for enteroviruses 71 (EV-71) were approved in China against HFMD, the availability and the acceptance of the vaccine in the Malaysia are unknown. This study investigated and ascertained the determinants of willingness-to-pay (WTP) for HFMD vaccination in Selangor Malaysia. This study adopted a cross-sectional, contingent valuation method involving 390 parents of young children aged six and below. The double bounded dichotomous choice (DBDC) approach was employed to assess the WTP for HFMD vaccine among respondents. A bivariate probit model was used to assess the key determinants of WTP for HFMD vaccine, while the mean WTP was measured using the Krinsky and Robb procedure. We found that 279 (71.5%) of parents were willing to pay for the HFMD vaccination. The estimated single bounded mean WTP was MYR460.23 (equivalent to US$ 102.17) for two doses of HFMD vaccination. The double bounded analysis revealed that the vaccine's price, poor education background and lower income were the key factors that significantly affected the WTP, with the estimated mean WTP being MYR394.00 (US$ 87.47). In conclusion, most Malaysian parents are willing to pay for the HFMD vaccination. The estimated WTP identifies the optimal price point for HFMD vaccination in Malaysia. Furthermore, the government should focus on an awareness programme for the HFMD vaccination among parents who have lower income or education level.

Vaccination inequities among children 12-23 months in India: An analysis of inter-state differences.

Background: Previous research has shown that socioeconomic and demographic risk factors in children are additive and lead to increasingly negative impacts on vaccination coverage. The goal of this study is to examine if different combinations of four risk factors (infant sex, birth order, maternal education level, and family wealth status) vary by state among children 12-23 months in India and to determine the impact of ≥ 1 risk factor on differences in state vaccination rates. Methods: Using data from the National Family Health Survey (NFHS) conducted in India between 2005 and 2006 (NFHS-3) and 2015-2016 (NFHS-4), full vaccination of children 12-23 months was examined. Full vaccination was defined as receipt of one dose of bacillus Calmette-Guérin (BCG), three doses of diphtheria-pertussis-tetanus vaccine (DPT) vaccine, three doses of oral polio vaccine (OPV), and one dose of measles-containing vaccine (MCV). Associations between full vaccination and the four risk factors were assessed using logistic regression. Data were analyzed by the state of residence. Results: A total of 60.9% of children 12-23 months were fully vaccinated, in NFHS-4, ranging from 33.9% in Arunachal Pradesh to 91.3% in Punjab. In NFHS-4, the odds of full vaccination across all states were 15% lower among infants with 2 risk factors versus 0 or 1 risk factors (OR: 0.85, 95% CI: 0.80-0.91), and 28% lower among infants with 3 or 4 risk factors versus 0 or 1 risk factor (OR: 0.72, 95% CI: 0.67-0.78). Overall, the absolute difference in the full vaccination coverage in those with > 2 vs < 2 risk factors decreased from -13% in NFHS-3 to -5.6% in NFHS-4, with substantial variation across states. Conclusions: Disparities in full vaccination exist among children 12-23 months experiencing > 1 risk factor. Indian states that are more populous or located in the north were more likely to have greater disparities.

US Residents' Preferences for Sharing of Electronic Health Record and Genetic Information: A Discrete Choice Experiment.

OBJECTIVES: The aim to this study was to assess preferences for sharing of electronic health record (EHR) and genetic information separately and to examine whether there are different preferences for sharing these 2 types of information. METHODS: Using a population-based, nationally representative survey of the United States, we conducted a discrete choice experiment in which half of the subjects (N = 790) responded to questions about sharing of genetic information and the other half (N = 751) to questions about sharing of EHR information. Conditional logistic regression models assessed relative preferences across attribute levels of where patients learn about health information sharing, whether shared data are deidentified, whether data are commercialized, how long biospecimens are kept, and what the purpose of sharing the information is. RESULTS: Individuals had strong preferences to share deidentified (vs identified) data (odds ratio [OR] 3.26, 95% confidence interval 2.68-3.96) and to be able to opt out of sharing information with commercial companies (OR 4.26, 95% confidence interval 3.42-5.30). There were no significant differences regarding how long biospecimens are kept or why the data are being shared. Individuals had a stronger preference for opting out of sharing genetic (OR 4.26) versus EHR information (OR 2.64) (P = .002). CONCLUSIONS: Hospital systems and regulatory bodies should consider patient preferences for sharing of personal medical records or genetic information. For both genetic and EHR information, patients strongly prefer their data to be deidentified and to have the choice to opt out of sharing information with commercial companies.

Demographic Differences in Compliance with COVID-19 Vaccination Timing and Completion Guidelines in the United States.

BACKGROUND: The development of vaccines has been a significant factor in eliminating the pandemic caused by the novel coronavirus (SARS-CoV-2). However, the primary series vaccination rate still falls short of our expectations, with an even lower rate of uptake for booster shots. This study examined demographic patterns of COVID-19 vaccination compliance by assessing patterns in the timing of the vaccine series start and vaccination completion and characterizing people by compliance with vaccination recommendations. METHODS: A cross-sectional survey was conducted online in August 2022. Participants answered questions about the COVID-19 vaccine and questions related to their personal backgrounds. We assessed the impact of demographic factors on COVID-19 vaccination using multivariable regression modeling. RESULTS: Among 700 eligible participants, 61% (389) were highly adherent (i.e., started by late 2020 and received a booster dose), 22% (184) were moderately adherent (i.e., started later than June 2021, and/or did not receive the booster dose), and 17% (127) were unvaccinated. Compliance was relatively low among non-Hispanic Black Americans, those with no religious affiliation, and among Independents and Republicans. CONCLUSION: Vaccination compliance varies across demographic groups. Race/ethnicity, religion, and political affiliation are highly associated with vaccination compliance. To promote vaccination compliance and decrease vaccine hesitancy, the government and healthcare institutions should establish a positive image to obtain public trust and adopt effective vaccine education and intervention.

Spillover of Vaccine Hesitancy into Adult COVID-19 and Influenza: The Role of Race, Religion, and Political Affiliation in the United States.

BACKGROUND: Due to its potential to lead to vaccine delays and refusals, vaccine hesitancy has attracted increased attention throughout the COVID-19 pandemic. It is crucial to investigate whether demographic patterns differ between adult general vaccine hesitancy and COVID-19 and flu vaccine non-receipt. METHODS: A cross-sectional survey was conducted online in August 2022. In response to questions about vaccine hesitancy, participants indicated whether they would receive the vaccine given various safety and efficacy profiles. Through logistic regression models, we examined variations between general vaccine hesitancy and COVID-19 non-vaccination. RESULTS: Among the 700 participants, 49% of the respondents were classified as having general vaccine hesitancy, 17% had not received the COVID-19 vaccine, and 36% had not had flu vaccinations. In the multivariable analysis, general vaccine hesitancy and the non-receipt of COVID-19 vaccines were significantly higher in Non-Hispanic Black participants, those with no religious affiliation, and Republicans and Independents. CONCLUSIONS: Patterns of vaccine hesitancy and the non-receipt of the COVID-19 vaccination did not vary, indicating a substantial overlap and potential spillover in vaccine hesitancy over the course of the pandemic. Because changing people's opinions regarding vaccinations is generally a challenge, different interventions specific to demographic subgroups may be necessary.

Experiences, risk perceptions, and COVID-19 vaccination outcomes among hospital workers.

BACKGROUND: Although COVID-19 vaccinations have been available to hospital workers in the U.S. since December 2020, coverage is far from universal, even in groups with patient contact. The aim of this study was to describe COVID-19-related experiences at work and in the personal lives of nurses, allied health workers, and non-clinical staff with patient contact, and to assess whether these experiences relate to COVID-19 vaccination. METHODS: Health care workers at a large Midwestern hospital in the U.S. were contacted to participate in an online cross-sectional survey during February 2021. A logistic regression model was used to estimate odds ratios (OR) for vaccination by different experiences, and we assessed mediation through models that also included measures of risk perceptions. RESULTS: Among 366 nurse practitioners / nurse midwives / physician assistant, 1,698 nurses, 1,798 allied health professionals, and 1,307 non-clinical staff with patient contact, the proportions who had received or intended to receive a COVID-19 vaccination were 94 %, 87 %, 82 %, and 88 %, respectively. Working and being physically close to COVID-19 patients was not significantly associated with vaccine intent. Vaccination intent was significantly lower among those with a previous COVID-19 diagnosis vs not (OR = 0.33, 95 % CI: 0.27, 0.40) and higher for those who knew close family members of friends hospitalized or died of COVID-19 (OR = 1.33, 95 % CI: 1.10, 1.60). CONCLUSION: Even when COVID-19 vaccination was available in February 2021, a substantial minority of hospital workers with patient contact did not intend to be vaccinated. Moreover, their experiences working close to COVID-19 patients were not significantly related to vaccination intent. Instead, personal experiences with family members and friends were associated with vaccination intent through changes in risk perceptions. Interventions to increase uptake among hospital workers should emphasize protection of close family members or friends and the severity of COVID-19.

COVID-19 vaccination refusal trends in Kenya over 2021.

BACKGROUND: Vaccination refusal exacerbates global COVID-19 vaccination inequities. No studies in East Africa have examined temporal trends in vaccination refusal, precluding addressing refusal. We assessed vaccine refusal over time in Kenya, and characterized factors associated with changes in vaccination refusal. METHODS: We analyzed data from the Kenya Rapid Response Phone Survey (RRPS), a household cohort survey representative of the Kenyan population including refugees. Vaccination refusal (defined as the respondent stating they would not receive the vaccine if offered to them at no cost) was measured in February and October 2021. Proportions of vaccination refusal were plotted over time. We analyzed factors in vaccination refusal using a weighted multivariable logistic regression including interactions for time. FINDINGS: Among 11,569 households, vaccination refusal in Kenya decreased from 24 % in February 2021 to 9 % in October 2021. Vaccination refusal was associated with having education beyond the primary level (-4.1[-0.7,-8.9] percentage point difference (ppd)); living with somebody who had symptoms of COVID-19 in the past 14 days (-13.72[-8.9,-18.6]ppd); having symptoms of COVID-19 in the past 14 days (11.0[5.1,16.9]ppd); and distrusting the government in responding to COVID-19 (14.7[7.1,22.4]ppd). There were significant interactions with time and: refugee status and geography, living with somebody with symptoms of COVID-19, having symptoms of COVID-19, and believing in misinformation. INTERPRETATION: The temporal reduction in vaccination refusal in Kenya likely represents substantial strides by the Kenyan vaccination program and possible learnt lessons which require examination. Going forward, there are still several groups which need specific targeting to decrease vaccination refusal and improve vaccination equity, including those with lower levels of education, those with recent COVID-19 symptoms, those who do not practice personal COVID-19 mitigation measures, refugees in urban settings, and those who do not trust the government. Policy and program should focus on decreasing vaccination refusal in these populations, and research focus on understanding barriers and motivators for vaccination.