Vaccine Acceptance Research Articles

Managing Information Overload in a Pandemic: Influence of Social Media on Vaccine Attitudes in the Digital Age

Purpose: This study examined how social media influences public health decisions, focusing on how information overload during a pandemic impacts vaccine hesitancy and acceptance across demographics. It analyzed conflicting vaccine information to understand social media's role in shaping attitudes and identify strategies to mitigate its negative effects. Methodology: This study employed a multi-stage sampling method to gather data from diverse age groups, education levels, and occupations. This approach combines various techniques at different stages, making it suitable for large, geographically dispersed populations. By segmenting the population into manageable units, multi-stage sampling improves the accuracy, reliability, and representativeness of the data collected. Findings: The findings reveal that most respondents consider vaccine information on social media unreliable, underscoring the need for greater trust in online discussions. Many feel overwhelmed by conflicting messages, highlighting the necessity for clearer communication. Social media significantly shapes attitudes toward COVID-19 vaccines, with many shifting views after engaging with online content. Additionally, participants report mental health impacts from the constant stream of vaccine information, illustrating information overload. Unique Contributions to Theory, Policy and Practice: This study advances the information overload model by illustrating how excessive and conflicting vaccine information on social media disrupts comprehension and harms mental health. It emphasizes social media's role in shaping health attitudes and advocates for interdisciplinary approaches that incorporate psychological resilience into public health strategies. Findings highlight the need for regulations against misinformation to improve the credibility of online health information and promote trusted sources, particularly verified health organizations. The study also calls for health literacy initiatives to empower the public in navigating misinformation and suggests strategies for managing information overload through social media disengagement. Targeted initiatives that leverage trusted information sources can effectively combat vaccine hesitancy and boost community engagement in public health campaigns, ultimately improving health outcomes.

Factors associated with HPV vaccine acceptance and hesitancy in Africa: a systematic review protocol

IntroductionHuman papillomavirus (HPV) infection is the most prevalent sexually transmitted infection worldwide. HPV vaccination is an important tool to prevent and control HPV infection and its complications. Despite carrying the...

Understanding the COVID-19 vaccine uptake, acceptance, and hesitancy in Ethiopia and Tanzania: a scoping review

BackgroundThe development and implementation of COVID-19 vaccines have been a breakthrough in controlling the pandemic. However, the vaccination coverage in most low-income countries remains very low due to critical vaccine shortage and profound hesitancy. In this scoping review, we aimed to assess COVID-19 vaccine uptake, acceptance, and hesitancy in Ethiopia and Tanzania.MethodsThe search was made in PubMed, Scopus, Embase, and Web of Science. Only original research articles focusing on vaccine acceptance and hesitancy were included. The studies selected for a full read were analysed using a thematic analysis approach.FindingsA total of 76 articles were included in the study, with 74 of them coming from Ethiopia. The study found an increasing trend in vaccine uptake over time. However, there was also an increase in hesitancy and a decline in willingness to receive the vaccine. The willingness to receive the COVID-19 vaccine in Ethiopia ranged from 18.5 to 88%. The main reasons for "vaccine hesitancy" included fear of side effects, concerns about long-term safety, doubts about vaccine effectiveness, lack of information, vaccine fast-tracking, and religious beliefs. The study also found that younger individuals, females, and pregnant women were less willing to receive the vaccine. The adverse events reported among vaccinated individuals were mostly mild. Most of the studies operationalised vaccine acceptance-hesitancy as dichotomous variables. However, the historical, political, and socio-cultural context in which vaccine acceptance and hesitancy occur was not given any attention. While there is a good amount of data from Ethiopia describing patterns of vaccine acceptance and hesitancy among different populations over time, there is limited information from Tanzania due to the late arrival of the vaccine and limited published articles.ConclusionWe have observed a paradox involving two seemingly conflicting trends: an increase in vaccination rates/coverage and "anti-vax." Most studies have simplified vaccine acceptance-hesitancy as an “either-or” incident, without considering its dynamic nature and occurrence within a broader political, social, and cultural context. Therefore, it is crucial to explore approaches that can enhance our understanding of the vaccine acceptance-hesitancy phenomenon, in order to improve vaccine trust and uptake.

Exploring the factors influencing the adult population's reluctance to accept the COVID-19 vaccine in Tehran.

While evidence of efficacy, safety, and technical feasibility is crucial when introducing a vaccine, it is equally important to consider the psychological, social, and political factors influencing vaccine acceptance. This study aims to identify the factors contributing to COVID-19 vaccine hesitancy among adults in Tehran, Iran. The study employed a descriptive and analytical cross-sectional design carried out from 2021 to 2022. It involved 260 eligible individuals residing in the catchment areas of Tehran and Shahid Beheshti Universities of Medical Sciences who declined to receive the COVID-19 vaccine, selected through systematic sampling. Data collection was accomplished through a researcher-developed questionnaire and analyzed using SPSS 26 software. The analysis utilized descriptive statistics and non-parametric tests including Mann-Whitney U, Kruskal-Wallis, and Multiple Linear Regression, to examine the relationships between variables. The average scores (SD) across dimensions were as follows: the individual's health status and perceived risk, 15.53 (1.70); contextual and social effects, 17.68 (2.53); awareness, 14.81 (2.34); and beliefs and concerns. 14.91 (2.64), indicating a concerning situation regarding contextual and social impacts and a moderate status as to other areas. The primary reasons for vaccine refusal included fear, lack of belief in the vaccine, concerns about its reliability, illness, and lack of access or time. Acceptance of the vaccine was associated with education, occupation, marital status, number of children at home, and income reduction due to COVID-19. The findings indicate that fear, lack of belief in the vaccine, concerns regarding its reliability, illness, and lack of access or time were the most important factors influencing reluctance to receive the vaccine. Health organizations should consider these factors when encouraging the population to receive the COVID-19 vaccine.

Evaluation et suivi des facteurs associés a l’acceptation de la vaccination contre la Covid-19 chez les habitants de la zone de santé de N’djili

This study aims to assess and monitor factors associated with COVID-19 vaccination acceptance among residents of the N’djili health zone. Using a methodological approach, we conducted survey among residents to collect data on their knowledge, attitudes, and perceptions about the vaccine. The results show that several factors influence vaccination acceptance, such as education level, access to information, trust in health authorities, and personal experiences related to COVID-19. Data analysis helps identify appropriate communication strategies to improve vaccine acceptance and mobeilize the population.

Acceptance of Human Papillomavirus (HPV) vaccine among the parents of eligible daughters (9-15 years) in Bangladesh: A nationwide study using Health Belief Model.

To align with the 2030 vision of the World Health Organization (WHO) to ensure 90% of girls receive the HPV vaccine before turning 15, Bangladesh has recently started the (HPV) vaccine campaign nationwide. Therefore, our study aimed to assess the level of its acceptance among parents of eligible daughters in Bangladesh. This nationwide cross-sectional study was conducted among the self-identified parents of daughters in the age group of 9-15 years between June 28 and August 2, 2023. A total of 2,151 parents were conveniently selected from all eight divisions of Bangladesh. Data was collected through face-to-face interviews using a semi-structured questionnaire. The Health Belief Model was used to appraise respondents' beliefs concerning HPV and its vaccination. Adjusted odds ratios (AOR) with a corresponding 95% confidence interval (CI), and a p-value of <0.05 was considered statistically significant. R Studio (Version 2023.09.0+463) was used as an interface for data analysis, while R (the programming language) was used for statistical computations. The mean age of the study participants was 38.18 (±5.86) years. The overall acceptance rate of the HPV vaccine was 86.61% (95%CI: 85.09-88.02). The vaccine acceptance level was positively associated with all the domains of the HBM (p<0.001), except in the perceived barrier domain (p = 0.489). After adjustment for other factors, it was found that higher age was associated with a decreased acceptance (AOR: 0.92; 95% CI: 0.89-0.95). The urban residents exhibited 42% lower odds of vaccine acceptance than rural (AOR: 0.58; 95% CI: 0.36-0.92). Similarly, participants of the middle-income group had 44% lower odds than the lower-income group (AOR: 0.56; 95% CI: 0.32-0.97). Our study found a reasonably good level of acceptance of the HPV vaccine among the parents of eligible daughters. Multiple factors such as younger age, urban residence, belonging to the middle income group, history of regular routine health check-ups, knowledge of cervical cancer, positive perception about benefits of the vaccine, and positive cues to actions were associated with HPV vaccine acceptance.

Understanding Parental Decision-Making and Determinants of COVID-19 Vaccination for Children in Vietnam: A Cross-Sectional Online Survey

Background/Objectives: In Vietnam, COVID-19 vaccination campaigns for children have encountered numerous challenges due to acceptance issues among parents. This study aimed to assess parental decision-making and identify factors influencing their decision to vaccinate their children against COVID-19. Methods: This was a cross-sectional online survey conducted between April and May 2023 among parents of children aged 6–17 years enrolled in urban and rural schools in Thai Nguyen province, Vietnam. Data on parental and child demographics, vaccination decision-making, COVID-19 experiences, and health beliefs based on the Health Belief Model were collected and analyzed, using univariate and multivariable multinomial regression analyses. Results: Among 4235 respondents (median age 41 years, 80.4% female), 81.3% had accepted all vaccine doses for their children, 9.7% had accepted some doses, 4.6% had rejected all doses, and 4.5% had not vaccinated their children for reasons unrelated to vaccine acceptance. Factors influencing parental decision-making included parental age, educational status, area of residence, health beliefs, prior experience with COVID-19 vaccination, and their child’s age and health status. Conclusions: We found overall high levels of parental acceptance for COVID-19 vaccination for children in Thai Nguyen province. To enhance COVID-19 vaccination acceptance, targeted communication strategies should focus on younger parents, those living in urban areas, parents with higher educational levels, and those with children who are younger or have underlying medical conditions. Trusted sources such as healthcare workers, teachers, and official health websites are essential for disseminating accurate information and fostering trust in vaccination programs.

Designing and Validating a Survey for National-Level Data During the COVID-19 Pandemic in Sri Lanka: Cross-Sectional Mobile Phone Surveys.

The COVID-19 pandemic has generated a demand for timely data, resulting in a surge of mobile phone surveys for tracking the impacts of and responses to the pandemic. Mobile phone surveys have become a preferred mode of data collection across low- and middle-income countries. This study piloted 2 population-based, cross-sectional mobile phone surveys among Sri Lankan residents in 2020 and 2021 during the COVID-19 pandemic. The surveys aimed to gather data on knowledge, attitudes, and practices, vaccine acceptability, availability, and barriers to COVID-19 testing, and use of a medicine distribution service. The study used Surveda, an open-source survey tool developed by the NCD (noncommunicable disease) Mobile Phone Survey Data 4 Health Initiative, for data collection and management. The surveys were conducted through interactive voice response using automated, prerecorded messages in Sinhala, Tamil, and English. The sample design involved random sampling of mobile phone numbers, stratified by sex, proportional to the general population. Eligibility criteria varied between surveys, targeting adults aged 35 years and older with any noncommunicable disease for the first survey and all adults for the second survey. The data were adjusted to population estimates, and statistical analysis was conducted using SAS (SAS Institute) and R software (R Core Team). Descriptive statistics, Rao-Scott chi-square tests, and z tests were used to analyze the data. Response rates, cooperation rates, and productivity of the sampling approach were calculated. In the first survey, n=5001, the overall response rate was 7.5%, with a completion rate of 85.6%. In the second survey, n=1250, the overall response rate was 10.9%, with a completion rate of 61.9%. Approximately 3 out of 4 adults reported that they avoided public places (888/1175, 75.6%), more than two-thirds avoided public transportation (808/1173, 68.9%), and 9 out of 10 practiced physical distancing (1046/1167, 89.7%). Approximately 1 out of 10 Sri Lankan persons reported being tested for COVID-19, and the majority of those received a polymerase chain reaction test (112/161, 70%). Significantly more males than females reported being tested for COVID-19 (98/554, 17.8% vs 61/578, 10.6%, respectively; P<.001). Finally, the majority of adult Sri Lankan people reported that they definitely or probably would get the COVID-19 vaccination (781/1190, 65.7%). The surveys revealed that, overall, the adult Sri Lankan population adhered to COVID-19 mitigation strategies. These findings underscore the use of mobile phone surveys in swiftly and easily providing essential data to inform a country's response during the COVID-19 pandemic, obviating the need for face-to-face data collection.

Effective communication by health care workers to promote HPV vaccination: Lessons learned from Kenya, India, and Nigeria

Health care workers play an essential role in maintaining the public trust in vaccination programmes globally, and more specifically, in low- and middle-income countries. This role is particularly important in building trust in the human papillomavirus (HPV) vaccine. While there are many factors that affect HPV vaccine acceptance, health care workers are one of the most critical influences in the decision-making process among parents as well as adolescent girls. In this paper, we sought to better understand how health care workers in a diverse set of countries communicate and promote HPV vaccines. We summarize communication approaches and lessons learned by health care workers in Kenya, India, and Nigeria through a case study approach. In Kenya, the utilization of a multisectoral approach proved to be very important. In India, intense social mobilization with targeted messaging by target audience laid the groundwork for community acceptance. An evolving communication strategy was essential in Nigeria, where there is no national HPV vaccination programme. Given the increase in vaccine hesitancy globally, the lessons learned through these three country examples highlight the importance of communication efforts in increasing vaccine acceptance.

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

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

Political and Community Logics of Emergent Disease Vaccine Deployment: Anthropological Insights from DRC, Uganda and Tanzania

With a growing number of emerging infectious diseases and the rapid development of vaccines during epidemics and pandemics, public health officials at the global and national level have reported concerns about vaccine hesitancy, often attributing this to a problem of misinformation and poor understanding of risk. However, social scientists have found that vaccination perceptions are complex and multi-faceted. By focusing on the historical, cultural and political influences that affect vaccine acceptance, as well as social justice questions that examine the fair distribution of vaccines, we explore the political and community logics of vaccine deployment using a case study approach. We found differing logics depending on the vaccine and the context and argue that political and community logics come to the forefront during outbreaks as vaccine strategies often are imposed—in different ways—by the Global North. We suggest that, prior to the development and deployment of new vaccines for emergent diseases in the Global South, political level and community logics must be acknowledged and engaged with.

AI based predictive acceptability model for effective vaccine delivery in healthcare systems

Vaccine acceptance is a crucial component of a viable immunization program in healthcare system, yet the disparities in new and existing vaccination adoption rates prevail across regions. Disparities in the rate of vaccine acceptance result in low immunization coverage and slow uptake of newly introduced vaccines. This research presents an innovative AI-driven predictive model, designed to accurately forecast vaccine acceptance within immunization programs, while providing high interpretability. Primarily, the contribution of this study is to classify vaccine acceptability into Low, Medium, Partial High, and High categories. Secondly, this study implements the Feature Importance method to make the model highly interpretable for healthcare providers. Thirdly, our findings highlight the impact of demographic and socio-demographic factors on vaccine acceptance, providing valuable insights for policymakers to improve immunization rates. A sample dataset containing 7150 data records with 31 demographic and socioeconomic attributes from PDHS (2017–2018) is used in this paper. Using the LightGBM algorithm, the proposed model constructed on the basis of different machine-learning procedures achieved 98% accuracy to accurately predict the acceptability of vaccines included in the immunization program. The association rules suggest that higher SES, region, parents’ occupation, and mother’s education have an association with vaccine acceptability.

COVID-19 vaccine uptake and associated factors among individuals living in a peri-urban area in Uganda: A cross-sectional study.

The Corona virus disease (COVID-19) is a respiratory illness that is caused by SARS-CoV-2 virus. This virus was first reported in China in December 2019. It then spread to all countries and from March 11, 2020, the World Health Organization declared the COVID-19 outbreak a pandemic. In Uganda, the disease was first reported in March 2020 and COVID-19 vaccines became available by January 2021. Although COVID-19 vaccines were available in Uganda, uptake remained low. The aim of this study was to establish COVID-19 vaccine uptake awareness in a peri-urban setting in Entebbe City, Uganda. This was a cross-sectional study conducted among 127 men and 263 women who reside in Entebbe City, Uganda. Data was collected on socio-behavioral characteristics, knowledge, attitude, and practice (KAP) about COVID-19 vaccine using interviewer administered questionnaires. Uptake of COVID-19 vaccine was defined as the proportion of participants who had received at least one dose of the COVID-19 vaccine. We used descriptive statistics to estimate awareness of COVID-19 vaccines. The 'chi-square test' and 'modified Poisson regression' were used to assess variations in uptake of COVID-19 vaccines among respondents and their socio-demographics as well as other characteristics. Ninety-nine percent (388 out of 390) of the study population were aware of at least one brand of COVID-19 vaccines in the country. Thirty-five percent (138 out of 390) knew that the vaccine immunity was achieved 14 days after the 2nd dose and 98.7% (385 out of 390) admitted that observing the standard operating procedure for COVID-19 infection prevention was necessary after vaccination. There was a gap in knowledge on vaccine safety reported by 74.6% (291 out of 390) participants. Some participants 37.2% (145 out of 390) had concerns about the vaccine. Of these, 57.9% (84 out of 145) believed that the vaccines were not helpful; and 30.3% (44 out of 145) feared serious side effects. Sixty-six percent (257 out of 390) believed that vaccines were not working and 79.0% (308 out of 390) admitted that vaccines were promoted for financial gain. At the time of performing the study, 36.2% and 22.3% had received the 1st and 2nd dose respectively. The main sources of information on COVID-19 vaccine were television (TV) and social media (p-value 0.001). In a multivariate model, COVID-19 vaccine acceptability was associated with salaried and self-employment (p-value 0.046). The other predicative factors were awareness of the COVID-19 vaccine (p-value <0.001) and having vaccine concerns (p-value 0.013). Uptake of COVID-19 vaccination in Entebbe community was low, partly attributed to knowledge gaps and concerns about vaccine safety and effectiveness. This highlights the need to enhance dissemination of information about COVID-19 vaccine. The lessons learnt in this study would be relevant for other emerging infections by informing vaccination implementation programs in similar settings.

Understanding COVID-19 Vaccine Acceptance Among Iranian Pregnant Women: Insights From a Multicenter Cross-Sectional Study.

Despite significant advancements in COVID-19 vaccine research and development, hesitancy in its acceptance, particularly among pregnant women, is recognized as a health threat. Based on the Health Belief Model, this study aimed to identify the factors influencing vaccine nonacceptance among pregnant women in the cities of Zahedan and Tabriz, Iran. The present research was a multicenter cross-sectional study conducted among pregnant women in two Iranian provinces, Zahedan and Tabriz, covering both high and low fertility regions. The study was conducted from February 2022 to August 2022. The sample size comprised 650 pregnant women attending selected healthcare centers. Data collection tools included questionnaires on sociodemographic characteristics, awareness, vaccine acceptance, and health beliefs related to vaccination. Data were analyzed using descriptive and analytical methods, including Analysis of variance (ANOVA), Independent t-test, and multivariable logistic regression. Among the 650 pregnant women, the vaccine acceptance rate was 47.4% and 52.6% of pregnant women reported vaccine nonacceptance during pregnancy. The logistic regression model indicated that the odds of vaccine acceptance increase with maternal employment (OR = 11.53, 95% CI: 4.81-27.63), higher maternal education levels (OR = 6.97, 95% CI: 3.11-15.63), higher income (OR = 1.60, 95% CI: 1.07-2.55), and increased awareness levels (OR = 1.37, 95% CI: 1.03-1.52). Additionally, the odds of vaccine acceptance increase with increased perceived susceptibility (OR = 2.55, 95% CI: 0.47-3.76), increased perceived benefits (OR = 2.22, 95% CI: 1.06-4.61), increased perceived barriers (OR = 0.42, 95% CI: 0.18-1.12), and increased cues to action (OR = 2.01, 95% CI: 1.03-3.92). Our study underscores the multifaceted nature of COVID-19 vaccine acceptance among pregnant women, with socioeconomic, awareness-related, and psychological factors all playing pivotal roles. These findings can inform targeted interventions and strategies aimed at increasing vaccine acceptance in this vulnerable population, ultimately contributing to enhanced maternal and fetal health during the ongoing pandemic.

Predictors of Human Papillomavirus (HPV) Vaccine Acceptability Among Physicians, Their Knowledge on Cervical Cancer, and Factors Influencing Their Decision to Recommend It

Predictors of Human Papillomavirus (HPV) Vaccine Acceptability Among Physicians, Their Knowledge on Cervical Cancer, and Factors Influencing Their Decision to Recommend It

Mpox Vaccine Acceptance, Democratic Republic of the Congo.

We report general acceptance (61.0%) of an mpox vaccine in the Democratic Republic of the Congo among 5,226 survey respondents. Healthcare workers and respondents in historic mpox-endemic regions had higher acceptance rates. These data highlight the need for increased community engagement and sensitization before widespread deployment of mpox vaccines.

Determinants of maternal acceptance of respiratory syncytial virus vaccination: knowledge gaps and influence of healthcare professionals

Determinants of maternal acceptance of respiratory syncytial virus vaccination: knowledge gaps and influence of healthcare professionals

Expanding Horizons: Increasing Injectable Vaccine in the Expanded Program on Immunization

The World Health Organization started the Expanded Program on Immunization in 1974, including 6 antigens with up to 8 vaccine doses for childhood vaccination. The number of antigens has now increased to 11 antigens in 21 vaccines. The expansion of vaccination programs to include more antigens and doses has led to concerns about the burden of multiple injections on infants and children, as well as factors such as fear of adverse reactions, pain, and overall acceptability of vaccines. To address these challenges, there's a call for research to focus on developing combined vaccines that can be administered through more acceptable routes, such as oral, nasal, or needleless administration. This approach could potentially reduce the number of injections required and increase the willingness of individuals to receive vaccines. We highlight the importance of ongoing research and innovation in vaccine development and delivery methods to ensure that vaccination programs remain effective, efficient, and acceptable to the communities they serve, particularly in resource-limited settings.

Laboratory-Confirmed Influenza Hospitalizations During Pregnancy or the Early Postpartum Period - Suzhou City, Jiangsu Province, China, 2018-2023.

Pregnancy is associated with increased risk for severe illness and complications associated with influenza infection. Insufficient knowledge about the risk for influenza among pregnant women and their health care providers in China is an important barrier to increasing influenza vaccination coverage and treating influenza and its complications among pregnant women. Improved influenza incidence estimates might promote wider vaccine acceptance and higher vaccination coverage. In Suzhou, active population-based surveillance during October 2018-September 2023 estimated that the annual rate of hospitalization for acute respiratory or febrile illness (ARFI) among women who were pregnant or <2 weeks postpartum was 11.1 per 1,000 live births; the annual rate of laboratory-confirmed influenza-associated ARFI (influenza ARFI) hospitalization in this group was 2.1 per 1,000 live births. A majority of hospitalized pregnant or early postpartum patients with ARFI (82.6%; 2,588 of 3,133) or influenza ARFI (85.5%; 423 of 495) were admitted to obstetrics wards rather than respiratory medicine wards. Only one (0.03%) pregnant or postpartum ARFI patient had received influenza vaccination, and 31.3% of pregnant or postpartum women hospitalized for influenza ARFI received antiviral treatment; the lowest percentage of hospitalized women with influenza ARFI who received antiviral treatment was among women admitted to obstetrics and gynecology wards (29.6% and 23.1%, respectively), compared with 54.1% of those admitted to a respiratory medicine ward. These findings highlight the risk for influenza and its associated complications among pregnant and postpartum women, the low rates of influenza vaccination among pregnant women, and of antiviral treatment of women with ARFI admitted to obstetrics and gynecology wards. Increasing awareness of the prevalence of influenza ARFI among pregnant women, the use of empiric antiviral treatment for ARFI, and the infection control in obstetrics wards during influenza seasons might help reduce influenza-associated morbidity among pregnant and postpartum women.

On-time childhood vaccination before and during the COVID-19 pandemic in seven communities: Findings from the New Vaccine Surveillance Network

BackgroundThe COVID-19 pandemic raised unprecedented challenges to vaccinating children. This multi-center study aimed to compare on-time vaccination of children before and during the COVID-19 pandemic and identify key factors associated with on-time vaccination. MethodsThis study was conducted among children aged 0–6 years enrolled in the New Vaccine Surveillance Network at seven geographically diverse U.S. academic medical centers. Children with acute respiratory illness or acute gastroenteritis were enrolled from emergency department and inpatient settings; healthy control subjects were enrolled from primary care practices. Vaccination data were collected and verified from patient medical records, immunization information systems, and/or provider documentation. On-time vaccination according to Advisory Committee on Immunization Practices recommendations was compared between pre-pandemic (December 2018–February 2020) and pandemic (March 2020–August 2021) periods using bivariate and multivariable analyses, adjusting for key demographic, clinical, and study characteristics. ResultsA total of 24,713 children were included in the analytic sample (non-Hispanic 73.4 %; White 51.0 %; publicly insured 69.0 %). On-time vaccination declined between the pre-pandemic (67.3 %) and pandemic (65.4 %) periods (Adjusted Odds Ratio 0.89, 95 % CI 0.84–0.95). The largest declines were observed among children who were < 12 months, male, Black, publicly insured, or whose mothers had a high school-equivalent education or less. The pandemic impact also varied by vaccine type and study site. ConclusionsThis multi-center study revealed a relatively modest overall reduction in on-time vaccination, which may reflect multilevel efforts to address pandemic-associated challenges. However, some patient subgroups and sites experienced greater reductions in on-time vaccination, highlighting the importance of tailoring interventions to increase equitable vaccine delivery, access, and acceptance across populations and communities.