COVID-19 vaccine hesitancy cannot fully explain disparities in vaccination coverage across the contiguous United States

SARS-CoV-2 Antibodies in Response to COVID-19 Vaccination in Underserved Racial/Ethnic Minority People Living with HIV

Background: Understanding immune response is essential for preparing for public health crises. COVID-19 vaccination provides robust immunity against SARS-CoV-2, but immunocompromised populations may have weaker immune responses. We assessed SARS-CoV-2 spike (trimer) total IgG/IgM/IgA (total Ig) to investigate immune response to COVID-19 vaccination in people living with HIV (PLWH), considering CD4+ T cell count, viral load, substance use, and comorbidities. Methods: This cross-sectional study was conducted in Miami, Florida, between May 2021 and December 2021 as part of the NIH Rapid Acceleration of Diagnostics-Underserved Populations (RADx-UP) initiative (3U01DA040381-05S1) and the Miami Adult Studies on HIV (MASH) cohort (U01DA040381). Blood samples were collected and SARS-CoV-2 spike (trimer) total Ig was quantified. HIV serostatus, viral load, CD4+ T cell count, and COVID-19 vaccinations were abstracted from medical records. Substance use (tobacco, alcohol, and drug use [marijuana, cocaine, heroin, fentanyl, methamphetamine, amphetamine, hallucinogens, ecstasy, or misuse of prescription drugs]), and comorbidities (hypertension, diabetes, autoimmune disease, obesity, chronic kidney disease, and substance use disorders) were assessed via validated questionnaires. Drug use was confirmed via urine toxicology. Multivariable linear regression was conducted. Results: Median age (n = 1317) was 57.8 years, 49.8% were male, 50% were Black non-Hispanic, 66.2% had received ≥1 dose of a COVID-19 vaccine, and 29.6% were PLWH (71.3% virally suppressed and median CD4+ T cell count > 500 cells/µL). PLWH, compared to people without HIV, were more likely to have received ≥1 dose of a COVID-19 vaccine (76.2% vs. 62.0%, p < 0.001) and present with substance use (77.2% vs. 42.9%, p < 0.001) and comorbidities (72.8% vs. 48.2%, p < 0.001). Vaccinated PLWH, compared to unvaccinated PLWH, had higher CD4+ T cell counts (577.5 vs. 517.5, p = 0.011) and were more likely to be virally suppressed (76.4% vs. 54.8%, p < 0.001). A lower CD4+ T cell count (<200 vs. ≥500, β = -0.400, p = 0.033) and higher HIV viral load (≥200-<5000 vs. <200, β = -0.275, p < 0.001) were associated with lower spike (trimer) total Ig titers, indicating a diminished response to COVID-19 vaccination. Conclusions: A lower CD4+ T cell count and higher HIV viremia were linked to reduced SARS-CoV-2 immunogenicity in racial/ethnic minority PLWH, a population underrepresented in vaccine clinical trials. HIV care providers should target efforts to maintain viral suppression to avoid diminished responses to COVID-19 vaccination.

Multi-level determinants of vaccination of the American Indian and Alaska Native population: a comprehensive overview

Context

American Indians and Alaska Natives (AIANs) are historically disadvantaged, losing 20 million (95%) of their population largely through epidemics since 1,520 and continuing lower overall vaccination coverage than other races. Determinants of this lower coverage are underexamined.

Methods

Among peer-reviewed relevant articles since 1968, 39 studied AIANs solely; 47 drew general population samples, including AIANs. We employed rigorous economic definitions and framework of Individual Decision-Making Under Uncertainty. The Social-Ecological model identified determinants and mechanisms at five levels.

Findings

Individual-level determinants include: (1) vaccine-preventable disease (VPD) and vaccine knowledge; (2) vaccine safety, efficacy, moral hazard beliefs; (3) preferences; (4) income and post-subsidy costs. Interpersonal-level determinants include others' knowledge and preferences. Organizational-level characteristics of Indian Health Service, Tribal, Urban Indian (IHS/T/U) facilities include: (1) supply of vaccine products, providers, services; (2) provider cultural competency, vaccine recommendations, standing orders; (3) patient reminder/recall. Community-level characteristics include: (1) socioeconomics and geographics; (2) information infrastructure; (3) cultural values, practices, languages; (4) historical epidemic knowledge; (5) historical harms thus distrust in government, health system, science. Societal-level determinants include: (1) federal recognition and entitlements; (2) tribal self-determination; (3) state Medicaid enrollment; (4) structural racism.

Policy recommendations

Tribal interventions may (1) increase AIANs' knowledge about VPDs, vaccines, Medicaid enrollment; (2) design risk/cost-benefit calculations using scientific objective probabilities of vaccine safety and efficacy; (3) tailor messages to epidemic histories, narratives, values; (4) outreach by trusted messengers. I/T/U organizational interventions may reduce transportation costs while increasing provider supplies, cultural competency, and vaccine standing orders. Federal policies may increase IHS funding, tribal infrastructure, and AIAN data representativeness while eliminating structural racism and generational trauma.

Conclusion

This article contributes to literature and practice. It is the first multidisciplinary, comprehensive overview of multi-level determinants and mechanisms of AIAN vaccination. Its findings highlight the gaps and limitations of laws and policies impacting AIAN vaccination. It recommends future research, culturally-appropriate interventions, and policies to close the gap to enhance AIAN vaccination and healing.

Modern approaches to predicting vaccine hesitancy: A scoping review

Introduction

Motivated by the disproportionate burden of infectious diseases on vulnerable populations and the risk of future pandemics, we conducted a scoping review to analyze the state of the literature about "vaccine uptake indices," defined as models that predict vaccination rates by geospatial area. We analyzed novel vaccine uptake indices created in response to the recent COVID-19 pandemic. The aim of this scoping review is to survey the state of the literature regarding vaccine uptake indices relating to COVID-19 and other infectious diseases.

Methods

We conducted a scoping review with a systematic search strategy to identify relevant articles from the databases Embase, PubMed, and Web of Science with title and abstract screening, full-text review, and data extraction.

Results

Database searches resulted in 3,615 potential articles, of which 229 reports were included. Fifteen studies (7%) were determined to be methodologically advanced vaccine uptake indices that had at least three of the following characteristics: the use of individual- and population-level predictor variables (100 [44%]), geo-spatiotemporal analysis (58 [25%]), data usage agnostic to vaccine specificity (50 [22%]), or sociobehavioral frameworks of health (such as the Health Belief Model and Theory of Planned Behavior) (30 [13%]).

Conclusion

This scoping review offers suggestions for future research of next-generation vaccine uptake indices before use in vaccination campaigns of recurring or novel infectious diseases. Areas to pursue include utilizing individual-level data about vaccination behaviors in conjunction with administrative data, solving the challenge of implementing small-area spatiotemporal analysis, using vaccine-agnostic methods that consider data from more than one infectious disease, and assisting causal inference with theoretical frameworks.

Sociopolitical antecedents influencing COVID-19 vaccine uptake in Pima County, Arizona

Introduction

Vaccine hesitancy among marginalized populations particularly in the Hispanic community over the course of the COVID-19 pandemic has presented as a public health issue. This study examined the relationship between political affiliation and vaccination decisions of Hispanic adults in Pima County, Arizona.

Methods

Between January and October 2022, 623 participants completed surveys in English or Spanish after completing informed consent process. Information collected included sociodemographic, political affiliation and philosophy and COVID vaccination uptake. Participants were recruited at different community events in Southern Tucson, Pima County, Arizona. Participants received five dollars for completing the surveys. Data were analyzed with Stata version 16.1.

Results

Participants were 81.8 % Hispanic and 18.2 % non-Hispanic. On average, participants were 32.9 (SD ± 11.8) years of age with a median age of 31 (IQR: 23, 41). Participants who had a bachelor's degree or above had 2.9 times greater odds of being vaccinated compared to those who had less than a high school education (Adjusted odds ratio (aOR): 2.84; 95 % CI: 1.12, 7.22). Individuals identifying as politically liberal had 3.28 times higher odds of being vaccinated compared to those identifying as conservative (OR = 3.28; 95 % CI: 1.5, 7.16). Similarly, Democrats had 3.36 times higher odds of being vaccinated than Republicans (OR = 3.36; 95 % CI: 1.61, 7.01). People who were strongly religious had statistically significantly lower odds of recommending the vaccine to others as compared to those who self-reported as not being religious.

Conclusions

There was an association with Hispanic adults who aligned liberal or Democrat to express more favorable views toward vaccinations. Additionally, individuals who were more educated, less religious, and in better financial situations tended to be more favorable toward vaccinations in Arizona.

Vaccine Intention, Uptake, and Hesitancy Among US Certified Food Producers: The National COVID-19 Organic Farmer Study

OBJECTIVE

To estimate COVID-19 vaccine intention, uptake, and hesitancy among essential workers.

METHODS

A cross-sectional survey of USDA-certified organic producers. An electronic survey was used for data collection. Analyses included descriptive statistics, χ2 tests, and ordinal logistic regressions.

RESULTS

The dataset consisted of 273 records. While 63% of respondents had received at least 1 dose of COVID-19 vaccine, only 17% had the recommended minimum of 2 doses. More than two-thirds of unvaccinated individuals indicated no plan to receive the vaccine, and limited perception of vaccine necessity. They indicated concerns about side effects and a distrust of the vaccines and the government. Age, education level, acreage, region, and health insurance status were variables significantly associated with the number of doses of vaccine received.

CONCLUSIONS

Interventions to encourage vaccination may target farmers who are less educated, live alone or just with one other person, lack health insurance, and run larger farms. Results also suggest focusing on enhancing trust in science and the government. Theory-based approaches that address low perception of risk and severity may be more likely to be effective with this population. Information on how US organic producers handled the COVID-19 pandemic is critical for emergency preparedness and food system stability.

Social network characteristics of COVID-19 vaccination and preventive health behaviors: Cross-sectional findings from the US northeast during the early COVID-19 pandemic

Background

The link between individuals' vaccine attitudes and their social networks has been widely studied, but less is known about how these networks impact broader health behaviors like precautionary measures during the COVID-19 pandemic.

Methods

Egocentric social network data were collected from June 7-21, 2021, via an online survey by researchers based at the Brown University School of Public Health. The sample (n = 173) was recruited through Amazon's Mechanical Turk in Connecticut, Massachusetts, New Jersey, New York, and Rhode Island. Participants reported their COVID-19 precautionary behaviors and those of up to 5 of their closest social network contacts (SNCs, n = 851). The primary outcome was the mean of 13 CDC-recommended precautionary behaviors (PBS). Covariates included SNCs' COVID-19 testing, hospitalization, vaccination, disease experiences, social distancing adherence, and encouragement of participants' testing and vaccination. Associations between PBS and SNC attributes were assessed using chi-square tests, t-tests, and Generalized Estimating Equations (GEE).

Results

Eighty percent of participants had received at least one vaccine dose. The PBS ranged from 0.38 to 3.00 (M = 2.3) and was positively associated with SNCs' adherence to social distancing guidelines (0.33, p < 0.001), encouragement of social distancing (0.33, p < 0.001), encouragement of vaccination (0.25, p = 0.001), mask-wearing behavior (0.20, p = 0.008), receiving the vaccine (0.20, p = 0.01), and encouragement of testing (0.17, p < 0.05).

Discussion

The clustering of precautionary behaviors in social networks highlights the potential of leveraging these networks to promote public health interventions. The identification of clusters of unprotected communities at risk underscores the need to address disparities and integrate interpersonal factors into future pandemic responses.

Health Care Delivery Site- and Patient-Level Factors Associated With COVID-19 Primary Vaccine Series Completion in a National Network of Community Health Centers

Objectives. To assess multilevel factors associated with variation in COVID-19 vaccination rates in a US network of community health centers. Methods. Using multilevel logistic regression with electronic health record data from ADVANCE (Accelerating Data Value Across a National Community Health Center Network; January 1, 2022-December 31, 2022), we assessed associations between health care delivery site-level (n = 1219) and patient-level (n = 1 864 007) characteristics and COVID-19 primary vaccine series uptake. Results. A total of 1 337 440 patients completed the COVID-19 primary vaccine series. Health care delivery site characteristics were significantly associated with lower series completion rates, including being located in non-Medicaid expansion states and isolated or rural communities and serving fewer patients. Patient characteristics associated with significantly lower likelihood of completing the vaccine series included being Black/African American or American Indian/Alaska Native (vs White), younger age, lower income, being uninsured or publicly insured (vs using private insurance), and having fewer visits. Conclusions. Both health care delivery site- and patient-level factors were significantly associated with lower COVID-19 vaccine uptake. Community health centers have been a critical resource for vaccination during the pandemic. (Am J Public Health. 2024;114(11):1242-1251. https://doi.org/10.2105/AJPH.2024.307773).

A Systematic Review of the Attitudes, Beliefs, and Acceptance of the COVID-19 Vaccine in the Western and Eastern Hemispheres

The availability of an effective vaccine does not equate to its use; its effectiveness primarily depends on vaccine acceptance by the targeted population. Despite the rapid development and widespread access to the COVID-19 vaccine, herd immunity is yet to be achieved, with vaccine hesitancy as a major barrier. This study sought to systematically assess the beliefs, attitudes, and acceptance towards COVID-19 vaccines, including factors contributing to vaccination hesitancy in the Eastern and Western Hemispheres. A comprehensive search of articles was conducted through Scopus, PubMed, Embase, CINAHL, Cochrane CENTRAL, and Web of Science databases for studies published from inception to May 2023 using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Our search yielded 1154, of which 21 were eligible for inclusion. The rate of willingness or intention to vaccinate varied with the geographic region, from 12% in the United States to 93.9% in China. Four studies from the Western region and two from the Eastern region reported a low acceptance rate (defined as <50%): United States (12%), Spain (48.3%), Switzerland (38.6%), Europe (multi-national, 31%), Nepal (38.3%), and Oman (43%). Overall, vaccine acceptance was low to moderate in the general population and healthcare workers (HCWs) in both Eastern and Western Hemispheres except for China which reported high acceptance (defined as >75%) among the general population and HCWs. Demographic characteristics (female, younger age, and higher education) and non-demographic factors (knowledge about the COVID-19 vaccine and its development, history of influenza vaccination, perceived susceptibility or severity of infection, and the belief that vaccines are effective in controlling the pandemic) were associated with high acceptance rates or intentions to take the COVID-19 vaccine. On the other hand, mistrust of the vaccine, its safety and effectiveness, disinformation or poor awareness of the vaccine, side effect concerns, belief in natural immunity, previous adverse experience with the vaccines, and distrust in the information sources about the COVID-19 pandemic were associated with vaccination hesitancy. For better acceptance, COVID-19 vaccination campaign strategies should be modeled based on regional political, economic, and social contexts.

Vaccine Confidence and Coverage among Medical Students at a Federal University in Brazil

BACKGROUND

Declining vaccination coverage (VC) and vaccine hesitancy among medical students are global challenges. These challenges reflect individual and logistical barriers to a sufficient adherence toward essential vaccines for healthcare professionals, as well as presenting a need for educational strategies during undergraduate training.

METHODS

This is a prospective study for evaluating VC rates, sociodemographic associations, and the vaccine confidence among medical students at a federal university in Brazil. The data collection included questionnaires and individual analyses of the participants' vaccination records.

RESULTS

A total of 237 medical students from all six years of an undergraduate program participated, of whom 124 (52.3%) had a vaccination record. Although the majority considered the vaccines to be "Completely Safe" (86.9%), the VC rates for complete vaccination schedules were relatively low, ranging from 87.9% (hepatitis B vaccine) to 3.2% (meningococcal B vaccine), including the vaccines from the National Immunization Program (NIP) and the private sector. Higher VC rates were found to occur among students in the final years of their undergraduate studies, in those from families with higher monthly incomes, and those from private secondary schools.

CONCLUSIONS

Given the low VC rates among medical students, other factors in addition to vaccine confidence may be determinants, thus highlighting the importance of reviewing policies for the inclusion of priority groups in the NIP and in implementing educational interventions during undergraduate training.

Unraveling Herpes Zoster Vaccine Hesitancy, Acceptance, and Its Predictors: Insights From a Scoping Review

Objectives

Herpes zoster vaccination is critical in preventing herpes zoster virus infection and its associated consequences. Despite its relevance, global herpes zoster immunisation coverage remains alarmingly low. Understanding the factors that drive vaccine scepticism and acceptance is crucial for increasing immunisation rates and improving public health outcomes.

Methods

This scoping review, following Joanna Briggs Institute guidelines, included 18 studies examining vaccine hesitancy, acceptance, and associated factors. Meticulous data analysis revealed hesitancy's intricate dynamics across countries and demographics.

Results

Studies displayed a wide range of acceptance rates (2.8%-89.02%), showcasing the complex interplay of attitudes and behaviors towards vaccination. Reasons for vaccine refusal were repeatedly identified in this setting, including worries about potential adverse effects, views of vaccine necessity, and vaccine supply constraints. Notably, individuals' patterns of vaccine acceptance and hesitancy differed among countries, vaccines, and vaccination-related factors.

Conclusion

Addressing acceptance hurdles by improving accessibility, providing accurate information, and strengthening healthcare recommendations is crucial. Understanding the multifaceted factors influencing hesitancy allows for targeted interventions, elevating immunization rates and enhancing public health globally.

Behavioral and social drivers of COVID-19 vaccination initiation in the US: a longitudinal study March─ October 2021

Many studies have examined behavioral and social drivers of COVID-19 vaccination initiation, but few have examined these drivers longitudinally. We sought to identify the drivers of COVID-19 vaccination initiation using the Behavioral and Social Drivers of Vaccination (BeSD) Framework. Participants were a nationally-representative sample of 1,563 US adults who had not received a COVID-19 vaccine by baseline. Participants took surveys online at baseline (spring 2021) and follow-up (fall 2021). The surveys assessed variables from BeSD Framework domains (i.e., thinking and feeling, social processes, and practical issues), COVID-19 vaccination initiation, and demographics at baseline and follow-up. Between baseline and follow-up, 65% of respondents reported initiating COVID-19 vaccination. Vaccination intent increased from baseline to follow-up (p < .01). Higher vaccine confidence, more positive social norms towards vaccination, and receiving vaccine recommendations at baseline predicted subsequent COVID-19 vaccine initiation (all p < .01). Among factors assessed at follow-up, social responsibility and vaccine requirements had the greatest associations with vaccine initiation (all p < .01). Baseline vaccine confidence, social norms, and vaccination recommendations were associated with subsequent vaccine initiation, all of which could be useful targets for behavioral interventions. Furthermore, interventions that highlight social responsibility to vaccinate or promote vaccination requirements could also be beneficial.

Health Care Access and COVID-19 Vaccination in the United States: A Cross-Sectional Analysis

BACKGROUND

Although federal legislation made COVID-19 vaccines free, inequities in access to medical care may affect vaccine uptake.

OBJECTIVE

To assess whether health care access was associated with uptake and timeliness of COVID-19 vaccination in the United States.

DESIGN

A cross-sectional study.

SETTING

2021 National Health Interview Survey (Q2-Q4).

SUBJECTS

In all, 21,532 adults aged≥18 were included in the study.

MEASURES

Exposures included 4 metrics of health care access: health insurance, having an established place for medical care, having a physician visit within the past year, and medical care affordability. Outcomes included receipt of 1 or more COVID-19 vaccines and receipt of a first vaccine within 6 months of vaccine availability. We examined the association between each health care access metric and outcome using logistic regression, unadjusted and adjusted for demographic, geographic, and socioeconomic covariates.

RESULTS

In unadjusted analyses, each metric of health care access was associated with the uptake of COVID-19 vaccination and (among those vaccinated) early vaccination. In adjusted analyses, having health coverage (adjusted odds ratio [AOR] 1.60; 95% CI: 1.39, 1.84), a usual place of care (AOR 1.58; 95% CI: 1.42, 1.75), and a doctor visit within the past year (AOR 1.45, 95% CI: 1.31, 1.62) remained associated with higher rates of COVID-19 vaccination. Only having a usual place of care was associated with early vaccine uptake in adjusted analyses.

LIMITATIONS

Receipt of COVID-19 vaccination was self-reported.

CONCLUSIONS

Several metrics of health care access are associated with the uptake of COVID-19 vaccines. Policies that achieve universal coverage, and facilitate long-term relationships with trusted providers, may be an important component of pandemic responses.

A population level study on the determinants of COVID-19 vaccination rates at the U.S. county level

Multiple COVID-19 vaccines were proven to be safe and effective in curbing severe illness, but despite vaccine availability, vaccination rates were relatively low in the United States (U.S.). To better understand factors associated with low COVID-19 vaccine uptake in the U.S., our study provides a comprehensive, data-driven population-level statistical analysis at the county level. We find that political affiliation, as determined by the proportion of votes received by the Republican candidate in the 2020 presidential election, has the strongest association with our response variable, the percent of the population that received no COVID-19 vaccine. The next strongest association was median household income, which has a negative association. The percentage of Black people and the average number of vehicles per household are positively associated with the percent unvaccinated. In contrast, COVID-19 infection rate, percentage of Latinx people, postsecondary education percentage, median age, and prior non-COVID-19 childhood vaccination coverage are negatively associated with percent unvaccinated. Unlike previous studies, we do not find significant relationships between cable TV news viewership or Twitter misinformation variables with COVID-19 vaccine uptake. These results shed light on some factors that may impact vaccination choice in the U.S. and can be used to target specific populations for educational outreach and vaccine campaign strategies in efforts to increase vaccination uptake.

Comparison of control and transmission of COVID-19 across epidemic waves in Hong Kong: an observational study

BACKGROUND

Hong Kong contained COVID-19 for two years but experienced a large epidemic of Omicron BA.2 in early 2022 and endemic transmission of Omicron subvariants thereafter. We reflected on pandemic preparedness and responses by assessing COVID-19 transmission and associated disease burden in the context of implementation of various public health and social measures (PHSMs).

METHODS

We examined the use and impact of pandemic controls in Hong Kong by analysing data on more than 1.7 million confirmed COVID-19 cases and characterizing the temporal changes non-pharmaceutical and pharmaceutical interventions implemented from January 2020 through to 30 December 2022. We estimated the daily effective reproductive number (Rt) to track changes in transmissibility and effectiveness of community-based measures against infection over time. We examined the temporal changes of pharmaceutical interventions, mortality rate and case-fatality risks (CFRs), particularly among older adults.

FINDINGS

Hong Kong experienced four local epidemic waves predominated by the ancestral strain in 2020 and early 2021 and prevented multiple SARS-CoV-2 variants from spreading in the community before 2022. Strict travel-related, case-based, and community-based measures were increasingly tightened in Hong Kong over the first two years of the pandemic. However, even very stringent measures were unable to contain the spread of Omicron BA.2 in Hong Kong. Despite high overall vaccination uptake (>70% with at least two doses), high mortality was observed during the Omicron BA.2 wave due to lower vaccine coverage (42%) among adults ≥65 years of age. Increases in antiviral usage and vaccination uptake over time through 2022 was associated with decreased case fatality risks.

INTERPRETATION

Integrated strict measures were able to reduce importation risks and interrupt local transmission to contain COVID-19 transmission and disease burden while awaiting vaccine development and rollout. Increasing coverage of pharmaceutical interventions among high-risk groups reduced infection-related mortality and mitigated the adverse health impact of the pandemic.

FUNDING

Health and Medical Research Fund.

US seniors' intention to vaccinate against RSV in fall and winter 2023-2024

In the fall and winter of 2023-2024, the United States may experience a "tripledemic" of COVID-19, influenza, and respiratory syncytial virus (RSV) that may lead to 100 000 deaths. Seniors will be disproportionally affected. The newly released RSV vaccines for those age 60 years and over may reduce the number of deaths for the expected 6000 to 10 000 seniors expected to die from RSV alone. Using a large national survey, we queried Americans over age 60 about their RSV vaccination status and their intention to vaccinate this fall and winter. We found that 9% of seniors had already been vaccinated. Of the remaining unvaccinated, 42% indicated their intent to vaccinate. We found that those with higher levels of concerns for the disease, higher levels of self-assessed risk, believing that vaccines were safe and important, higher levels of trust in health institutions, and men were more likely to seek out vaccinations. Vaccine-hesitant respondents listed a lack of necessity, concerns about side effects and safety, and a lack of information as primary reasons. The large number of unvaccinated seniors will likely lead to an excessive number of hospitalizations and deaths as well as augmented social costs. Evidence-based mitigation measures tailored to seniors' concerns should be implemented immediately.

Community-Engaged Research: COVID-19 Testing, Infection, and Vaccination among Underserved Minority Communities in Miami, Florida

Community collaboration is a cornerstone of modern public health efforts. This work aimed to use community-engaged research to explore COVID-19 vaccination, testing, and infection in a minoritized community. This study was conducted in Miami, Florida, from March 2021 to February 2022 in community partner sites and the Miami Adult Studies on HIV (MASH) cohort. Sociodemographic characteristics, vaccination and testing beliefs, and COVID-19 challenges were self-reported. COVID-19 vaccinations were verified with medical records, testing history was self-reported, and severe acute respiratory syndrome coronavirus 2 positivity was determined via real-time reverse transcription-polymerase chain reaction (rt-PCR). Of 1689 participants, the median age was 57, 51% were male, 49% were non-Hispanic Black, 66% reported an income < USD 15,000/year, and 75.9% received at least one dose of a COVID-19 vaccine. Belief that COVID-19 vaccination is effective was associated with lower odds of COVID-19 positivity and was the strongest predictor of vaccination. Challenges accessing health care, housing, food, and transportation were associated with lower odds of vaccination. Employment, health insurance, higher education, and greater perceived test accuracy were associated with greater odds of COVID-19 testing. Social determinants of health and the belief that vaccines are effective and tests are accurate predicted behaviors and thus should be considered during public health crises in vulnerable communities.

Relationship between vaccine hesitancy and vaccination behaviors: Systematic review and meta-analysis of observational studies

BACKGROUND

Vaccination is crucial for prevention of infectious diseases, and identification of the impact of vaccine hesitancy on vaccination programs is crucial for early intervention and formulation of policies to alleviate vaccine hesitancy. The aim of this systematic review was to explore the relationship between vaccine hesitancy and negative vaccination behavior globally.

METHODS

We searched for observational studies in various databases. We conducted a meta-analysis using pooled odds ratios (OR) and 95 % confidence intervals (CI), performed meta regression and subgroup analysis to explore the role factors such as location and individual characteristics on the association between vaccine hesitancy and vaccination behavior.

RESULTS

A total of 46 articles were included in systematic analysis and 34 articles were included in the meta-analysis. The systematic analysis comprised 162,601 samples, whereas the meta-analysis included 147,554 samples. The meta-analysis showed that a higher rate of vaccine hesitancy was associated with an increased likelihood of adverse vaccination behaviors (all adverse behaviors: OR = 1.50, 95 % CI, 1.33-1.70, P < 0.001; unvaccinated: OR = 1.48, 95 % CI, 1.29-1.70, P < 0.001; vaccine delay: OR = 2.61, 95 % CI, 1.97-3.44, P < 0.001). The meta-regression results indicated that the heterogeneity observed was mainly from sample selection methods, age of vaccinees and the health status of participants. The results showed that parents of minor vaccinees or without high-risk health status had a higher association between vaccine hesitancy and vaccine uptake compared with populations exposed to higher health risks or adult vaccinees.

CONCLUSION

The findings provide evidence on the association between vaccine hesitancy and adverse vaccination behaviors. The results showed that these population-specific factors should be considered in future research, and during formulation of interventions and implementation of policies to improve vaccination uptake.

Assessing parental intention to vaccinate against COVID-19, influenza, and RSV in the United States in late 2023

Vaccine hesitancy is a substantial public health threat. We used a national survey to query parents about their intention to vaccinate their children against COVID-19, influenza, and RSV in the fall and winter 2023-2024. We found that about 40% of parents intended to vaccinate their children against COVID-19, 63% against influenza, and 71% against RSV. Intention to vaccinate was consistently correlated with concerns about the disease, trust in health institutions, and previous vaccinations. Women showed lower intentions for COVID-19 and influenza. For COVID-19 and RSV, intentions were higher for those who thought vaccines were important. Concerns about autism were negatively associated for COVID-19. Liberals showed larger intentions for COVID-19. Major reasons for hesitancy include concerns about safety, necessity, and lack of information. The large number of unvaccinated children will likely lead to large numbers of excessive disease in children as well as exert large negative externalities on society at large.

Assessing vaccine hesitancy and support for vaccination requirements for pets and potential Spillovers from humans

BACKGROUND

Growing vaccination hesitancy is well-document among humans. However, we know very little about vaccination hesitancy for pets as well as whether the two phenomena are interconnected. Moreover, support for pet vaccination requirements also remain underassessed.

METHODS

We fielded a large, national survey (N = 3,958) on August 18 and August 19, 2023, to assess U.S. public opinion about the vaccination status of dogs (rabies, canine parvovirus, canine distemper, canine influenza, and Lyme disease) and cats (rabies, feline panleukopenia (parvo), feline herpesvirus-1, feline chlamydia, and feline Bordetella) in the United States. We also queried respondents about their support for vaccination requirements for the 10 diseases.

RESULTS

We find that the vast majority of cats and dogs are vaccinated. However, a substantial minority of pets is not, particularly for cats and for non-core vaccines. We find that attitudinal measures of human and pet vaccine hesitancy are closely related to each other. Moreover, they are strong predictors of vaccine behavior. Measures of vaccine hesitancy are also strong predictors of support for vaccination mandates. Common measures used to assess human vaccine hesitancy showed inconsistent effects. However, pet vaccinations appear to be less politically polarizing.

CONCLUSION

The high correlation between pet and human measures raises the stake for public health efforts to improve attitudes about vaccines and vaccination rates across the board. Strong support for vaccination requirements should encourage policymakers to explore policy change. Moreover, veterinarians and their associations should consider expanding the number of core vaccinations.

Vaccination coverage of primary care providers against seasonal influenza, tetanus, pneumococcal pneumonia and herpes zoster: A cross-sectional study in Greece

Introduction

Primary care providers' (PCPs) compliance to self-immunization is important for their protection and the protection of their colleagues and patients and has been associated with the coverage of the general public. In this study, we aim to investigate the vaccination coverage of PCPs.

Methods

A questionnaire-based cross-sectional survey was conducted among physicians, nurses and pharmacists employed in public or private primary care settings in Greece. Demographic and occupational characteristics as well as vaccination coverage data for influenza, tetanus, pneumococcal pneumonia and herpes zoster were collected. Statistical significance was set at 0.05.

Results

In total, 748 (61.7% response rate) PCPs participated. Vaccination rates were 66.4% (496/747) for influenza (2019/2020 flu season), 62.9% (469/746) for tetanus (10-year Td or Tdap booster dose), 70% (14/20) for pneumococcal pneumonia (≥ 1 dose of PPSV23 or PCV13) and 12.3% (10/81) for herpes zoster. Multiple logistic regression revealed that nurses had significantly lower probability of being vaccinated against influenza [odds ratio (OR) = 0.25; 95% confidence interval (CI) = 0.14-0.45] and pharmacists had significantly lower probability of being vaccinated against both influenza (OR = 0.44; 95% CI = 0.31-0.62) and influenza & tetanus (OR = 0.52; 95% CI = 0.37-0.73) compared to physicians. Older age (>40 years) was an independent risk factor for not receiving a tetanus vaccine (40-49 vs. 19-39; OR = 0.42; 95% CI = 0.28-0.63, over 50 years old vs. 19-39; OR = 0.54; 95% CI = 0.36-0.79).

Conclusions

The results revealed suboptimal vaccination rates among health providers who are in the frontline of adult immunization. Individualized and targeted measures to improve their vaccination coverage and indirectly the vaccination coverage of their patients, are therefore required.

Novel Psychosocial Correlates of COVID-19 Vaccine Hesitancy: Cross-Sectional Survey

BACKGROUND

Effective COVID-19 vaccines have been available since early 2021 yet many Americans refuse or delayed uptake. As of mid-2022, still around 30% of US adults remain unvaccinated against COVID-19. The majority (81%) of these unvaccinated adults say they will "definitely not" be getting the COVID-19 vaccine. Understanding the determinants of COVID-19 vaccine uptake is critical to reducing death and illness from the virus, as well as to inform future vaccine efforts, such as the more recent bivalent (omicron) booster.

OBJECTIVE

This study aimed to expand our understanding of psychosocial determinants of COVID-19 vaccine uptake. We focus on both COVID-19-specific factors, such as COVID-19 conspiracy beliefs, as well as more global personality attributes such as dogmatism, reactance, gender roles, political beliefs, and religiosity.

METHODS

We conducted a web-based survey in mid-2021 of a representative sample of 1376 adults measuring both COVID-19-specific beliefs and attitudes, as well as global personality attributes. COVID-19 vaccination status is reported at 3 levels: vaccinated; unvaccinated-may-get-it; unvaccinated-hard-no.

RESULTS

Our analyses focused on the correlation of COVID-19 vaccination status with 10 psychosocial attributes: COVID-19-specific conspiracy theory beliefs; COVID-19 vaccine misinformation; COVID-19-related Rapture beliefs; general antivaccination beliefs; trait reactance; trait dogmatism; belief in 2020 election fraud; belief in a QAnon conspiracy; health care system distrust; and identification with traditional gender roles. We used a multivariate analysis of covariance to examine mean differences across vaccine status groups for each of the correlates while holding constant the effects of age, gender, race, income, education, political party, and Evangelicalism. Across the 10 psychosocial correlates, several different response scales were used. To allow for comparison of effects across correlates, measures of effect size were computed by converting correlates to z scores and then examining adjusted mean differences in z scores between the groups. We found that all 10 psychosocial variables were significantly associated with vaccination status. After general antivaccination beliefs, COVID-19 misinformation beliefs and COVID-19 conspiracy beliefs had the largest effect on vaccine uptake.

CONCLUSIONS

The association of these psychosocial factors with COVID-19 vaccine hesitancy may help explain why vaccine uptake has not shifted much among the unvaccinated-hard-no group since vaccines became available. These findings deepen our understanding of those who remain resistant to getting vaccinated and can guide more effective tailored communications to reach them. Health communication professionals may apply lessons learned from countering related beliefs and personality attributes around issues such as climate change and other forms of vaccine hesitancy. For example, using motivational interviewing strategies that are equipped to handle resistance and provide correct information in a delicate manner that avoids reactance.

Analysis of COVID-19 Case Demographics and Disease Outcomes in Gary, Indiana

BACKGROUND

The COVID-19 pandemic further exposed the prevalence of existing health disparities in Black communities in the U.S. The current study evaluates COVID-19 data collected in Gary, Indiana, from June 2020 to June 2021. We hypothesized that the number of COVID-19 cases, hospitalizations, and deaths were influenced by race and income.

METHODS

In collaboration with the Gary Health Department (GHD), we analyzed demographic data on COVID-19-positive cases.

RESULTS

Compared to Gary's non-Black population, age- and population-adjusted rates of hospitalizations and deaths in the Black population were 3-fold (p < 0.0001) and 2-fold (p < 0.05) higher, respectively. This is despite a higher infection rate (p < 0.0001) in the non-Black population. The median household income of a zip code was negatively correlated with COVID-19 hospitalizations (R2 = 0.6345, p = 0.03), but did not correlate with infections and deaths.

CONCLUSIONS

The current study demonstrates clear health disparities of income and race in the context of COVID-19-related infections and outcomes in the city of Gary. Indiana University School of Medicine Northwest and GHD officials can collaborate to utilize these data for the reallocation of resources and health education efforts in Gary's highly populated, low-income, and predominantly Black neighborhoods. It should also prompt further investigation into national health resource allocation.

Social processes, practical issues, and COVID-19 vaccination among hesitant adults

INTRODUCTION

The purpose of this study is to examine relationships between COVID-19 vaccination, social processes, and the practical issues of healthcare coverage and workplace requirements. We examine these relationships among individuals who expressed some degree of hesitancy towards receiving the vaccine. Assessing relationships between COVID-19 vaccination, social processes, and practical issues among vaccine-hesitant individuals has implications for public health policy and intervention.

METHODS

We analyzed weighted data from a random sample phone survey of Arkansas adults (N = 2,201) between March 1st and March 28th, 2022 and constrained our analytical sample to those who had reported some degree of vaccine hesitancy (N = 1,251). Statistical analyses included weighted and unweighted descriptive statistics, weighted bivariate logistic regressions, and a weighted multivariate logistic regression to obtain adjusted odds ratios for COVID-19 vaccination.

RESULTS

More than two-thirds (62.5 %) of respondents were vaccinated, despite their hesitancy. Adjusted odds of COVID-19 vaccination were greater among Black (OR = 2.55; 95 % CI[1.63, 3.97]) and Hispanic respondents (OR = 2.46; 95 % CI[1.53, 3.95]), respondents whose healthcare provider recommended vaccination (OR = 2.50; 95 % CI[1.66, 3.77]), and as perceptions of vaccination coverage (OR = 2.04; 95 % CI[1.71, 2.43]) and subjective social status increased (OR = 1.10; 95 % CI[1.01, 1.19]). Adjusted odds of COVID-19 vaccination were greater among respondents with a workplace that recommended (OR = 1.96; 95 % CI[1.03, 3.72]) or required vaccination (OR = 12.62; 95 % CI[4.76, 33.45]) and among respondents who were not employed (OR = 1.82; 95 % CI[1.10, 3.01]) compared to those whose workplace did not recommend or require COVID-19 vaccination.

CONCLUSIONS

Some hesitant individuals become vaccinated despite their hesitancy-a group we refer to as "hesitant adopters." Social processes and practical issues are important correlates of vaccination among those who are hesitant. Workplace requirements appear to be of particular importance for vaccination among hesitant individuals. Provider recommendations, norms, social status, and workplace policies may be effective points of intervention among those who express vaccine hesitancy.

Vaccination, human mobility, and COVID-19 health outcomes: Empirical comparison before and during the outbreak of SARS-Cov-2 B.1.1.529 (Omicron) variant

The B.1.1.529 (Omicron) variant surge has raised concerns about the effectiveness of vaccines and the impact of imprudent reopening. Leveraging over two years of county-level COVID-19 data in the US, this study aims to investigate relationships among vaccination, human mobility, and COVID-19 health outcomes (assessed via case rate and case-fatality rate), controlling for socioeconomic, demographic, racial/ethnic, and partisan factors. A set of cross-sectional models was first fitted to empirically compare disparities in COVID-19 health outcomes before and during the Omicron surge. Then, time-varying mediation analyses were employed to delineate how the effects of vaccine and mobility on COVID-19 health outcomes vary over time. Results showed that vaccine effectiveness against case rate lost significance during the Omicron surge, while its effectiveness against case-fatality rate remained significant throughout the pandemic. We also documented salient structural inequalities in COVID-19-related outcomes, with disadvantaged populations consistently bearing a larger brunt of case and death tolls, regardless of high vaccination rates. Last, findings revealed that mobility presented a significantly positive relationship with case rates during each wave of variant outbreak. Mobility substantially mediated the direct effect from vaccination to case rate, leading to a 10.276 % (95 % CI: 6.257, 14.294) decrease in vaccine effectiveness on average. Altogether, our study implies that sole reliance on vaccination to halt COVID-19 needs to be re-examined. Well-resourced and coordinated efforts to enhance vaccine effectiveness, mitigate health disparity and selectively loosen non-pharmaceutical interventions are essential to bringing the pandemic to an end.

The Moderating Effect of Vaccine Hesitancy on the Relationship between the COVID-19 Vaccine Coverage Index and Vaccine Coverage

To examine COVID-19 vaccination barriers in the US, this study drew on publicly available county-level data (n = 3130) to investigate the impact of vaccine hesitancy on the relationship between county-level social/structural barriers and vaccine coverage. A hierarchical regression was performed to establish the relationship between the COVID-19 Vaccine Coverage Index (CVAC) and vaccine coverage, assess the moderating effect of vaccine hesitancy on this relationship, and explore the influence of ethno-racial composition on vaccine coverage. A significant, negative relationship (r² = 0.11, f² = 0.12) between CVAC and vaccine coverage by county was established (step 1). When vaccine hesitancy was introduced as a moderator (step 2), the model significantly explained additional variance in vaccine coverage (r² = 0.21, f² = 0.27). Simple slopes analysis indicated a significant interaction effect, whereby the CVAC-vaccine coverage relationship was stronger in low hesitancy counties as compared with high hesitancy counties. Counties with low social/structural barriers (CVAC) but high hesitancy were projected to have 14% lower vaccine coverage. When county-level ethno-racial composition was introduced (step 3), higher proportions of white residents in a county predicted decreased vaccination rates (p < 0.05). Findings indicate that CVAC should be paired with vaccine hesitancy measures to better predict vaccine uptake. Moreover, counties with higher proportions of white residents led to decreases in vaccine uptake, suggesting that future intervention strategies should also target whites to reach herd immunity. We conclude that public health leaders and practitioners should address both social/structural and psychological barriers to vaccination to maximize vaccine coverage, with a particular focus on vaccine hesitancy in communities with minimal social/structural barriers.

Role of perceived social support in COVID-19 vaccine uptake among U.S. adults

Background

Vaccine uptake concerns in the Unites States were at the forefront of public health discussions during the COVID-19 pandemic. By the end of 2022, approximately 80% of the U.S. population was vaccinated against the virus. This study examined the relationship between perceived social support and COVID-19 vaccine uptake among U.S. adults.

Methods

Using nationally representative cross-sectional data on 21,107 adults from the 2021 National Health Interview Survey, we assessed the COVID-19 vaccination rates across individuals with strong, some, and weak levels of social support. Multivariable logistic regression models were estimated to obtain the odds of being vaccinated in adults with different levels of perceived social support for the full sample and sub-samples of age groups.

Results

We found that compared to adults with perceived strong social support, adults with weak social support were 21.1% less likely to be vaccinated against COVID-19. Apart from the age 18-24 years group, the lower likelihood of being vaccinated for adults with weak social support was evident in age 24-49 years (AOR=0.66, 95% CI: 0.52-0.85), age 50-64 years (AOR=0.67, 95% CI: 0.50-0.90), and age 65+ years (AOR=0.56, 95% CI: 0.41-0.75) groups.

Conclusions

These findings are consistent with a broader literature indicating that social support increases the likelihood of healthy behaviors and decreases risky behaviors. Interventions designed to improve the perception of social support, particularly among those at high risk of mortality from COVID-19 may be a promising tactic for increasing COVID-19 vaccine uptake.

Incomplete HPV Vaccination among Individuals Aged 27-45 Years in the United States: A Mixed-Effect Analysis of Individual and Contextual Factors

Background: In the United States, the human papillomavirus (HPV) vaccine is approved for use in individuals up to age 45. Individuals 15 years and older require three doses of the vaccine to complete the recommended dosing series. Incomplete HPV vaccination rates (i.e., one or two doses) among those over age 26, however, remain high. This study examined the independent effects of individual- and neighborhood-level factors on incomplete HPV vaccination rates in the United States (U.S.) among those aged 27-45 years. Methods: This retrospective cohort study used administrative data from Optum's de-identified Clinformatics® Data Mart Database to identify individuals aged 27-45 years who received one or more doses of HPV vaccine between July 2019 and June 2022. Multilevel multivariable logistic regression models were applied to the data on 7662 individuals identified as being fully or partially vaccinated against HPV, nested within 3839 neighborhoods across the U.S. Results: Approximately half of the patients in this study (52.93%) were not completely vaccinated against HPV. After adjusting for all other covariates in the final model, being older than 30 years old decreased the odds of not completing the HPV vaccine series. Participants living in South-region neighborhoods of the U.S. had enhanced odds of not completing the vaccine series compared with those residing in Northeast-region neighborhoods (aOR 1.21; 95% CrI 1.03-1.42). There was significant clustering of incomplete HPV vaccination rates at the neighborhood level. Conclusions: This study revealed that individual- and neighborhood-level factors were associated with the risk of not completing the HPV vaccine series among individuals aged 27-45 years in the U.S. Interventions to improve HPV vaccination series completion rates for this age group should take into consideration both individual and contextual factors.

Social Determinants of COVID-19 Vaccination Rates: A Time-Constrained Multiple Mediation Analysis

Objective To estimate the multiple direct/indirect effects of social, environmental, and economic factors on COVID-19 vaccination rates (series complete) in the 3109 continental counties in the United States (U.S.). Study design  The dependent variable was the COVID-19 vaccination rates in the U.S. (April 15, 2022). Independent variables were collected from reliable secondary data sources, including the Census and CDC. Independent variables measured at two different time frames were utilized to predict vaccination rates. The number of vaccination sites in a given county was calculated using the geographic information system (GIS) packages as of April 9, 2022. The Internet Archive (Way Back Machine) was used to look up data for historical dates. Methods  A chain of temporally-constrained least absolute shrinkage and selection operator (LASSO) regressions was used to identify direct and indirect effects on vaccination rates. The first regression identified direct predictors of vaccination rates. Next, the direct predictors were set as response variables in subsequent regressions and regressed on variables that occurred before them. These regressions identified additional indirect predictors of vaccination. Finally, both direct and indirect variables were included in a network model. Results  Fifteen variables directly predicted vaccination rates and explained 43% of the variation in vaccination rates in April 2022. In addition, 11 variables indirectly affected vaccination rates, and their influence on vaccination was mediated by direct factors. For example, children in poverty rate mediated the effect of (a) median household income, (b) children in single-parent homes, and (c) income inequality. For another example, median household income mediated the effect of (a) the percentage of residents under the age of 18, (b) the percentage of residents who are Asian, (c) home ownership, and (d) traffic volume in the prior year. Our findings describe not only the direct but also the indirect effect of variables. Conclusions  A diverse set of demographics, social determinants, public health status, and provider characteristics predicted vaccination rates. Vaccination rates change systematically and are affected by the demographic composition and social determinants of illness within the county. One of the merits of our study is that it shows how the direct predictors of vaccination rates could be mediators of the effects of other variables.

The Relationship between Health Literacy and COVID-19 Vaccination Prevalence during a Rapidly Evolving Pandemic and Infodemic

The gap between how health information is communicated and what people understand and can use to make informed health decisions is called health literacy. This gap was exacerbated by the rapidly changing and excessive volume of information, misinformation, and disinformation during the COVID-19 pandemic. People with lower health literacy may not have understood the importance of COVID-19 vaccination for themselves or for their communities. Our aim was to understand health literacy levels within Fulton County, Georgia, and their relationship to vaccine prevalence. Fulton county residents ages 18 and over (n = 425) completed an on-line Health Literacy Questionnaire. Individual, organizational, functional, interactive, and critical health literacy scales were created. Vaccination prevalence data were collected from the Georgia Vaccine Distribution Dashboard. All data were divided into one of three county areas. There were statistically significant variations in vaccine prevalence χ2(3) = 29.325, p < 0.001 among the three county areas. All levels of health literacy predicted overall county vaccination prevalence F (4,420) = 85.941, p < 0.001, There were significant differences in health literacy levels among two of the three county area pairs; the lowest resourced county area had the lowest vaccination prevalence and health literacy rates. This is the first example of relating direct health literacy measures across a major metropolitan US county with vaccine prevalence data.