Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
8.9
5.2
Journals
Vaccines
Special Issues
Impact of Immunization Safety Monitoring on Vaccine Coverage
share announcement

Impact of Immunization Safety Monitoring on Vaccine Coverage

A special issue of Vaccines (ISSN 2076-393X). This special issue belongs to the section "Human Vaccines and Public Health".

Deadline for manuscript submissions: 25 August 2025 | Viewed by 8429

Special Issue Editor

Dr. Jane F. Gidudu

E-Mail
Guest Editor
Global Immunization Division, Centers for Disease Control and Prevention, Atlanta, GA, USA
Interests: immunization safety

Special Issue Information

Dear Colleagues,

Despite progress in immunization recovery, immunization coverage remains lower than before the COVID-19 pandemic. Global immunization stakeholders have committed to achieving immunization recovery and reaching zero-dose communities. They are focusing their efforts on raising vaccination levels and protecting vulnerable and special populations from vaccine-preventable diseases. In addition to ensuring equitable access to immunizations, it is essential to consider immunization safety concerns, as they are a significant driver of vaccine hesitancy.

This Special Issue aims to highlight immunization safety in improving immunization coverage. We welcome original research articles and reviews focusing on research areas that include disparities in immunization coverage, immunization safety, active vaccine safety surveillance, adverse events following immunization, digital innovations for immunization program monitoring, barriers to reporting immunization safety events, advances to address immunization safety information and strategies to increase the demand for vaccines.

Dr. Jane F. Gidudu
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Vaccines is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • vaccine safety
  • immunization safety
  • adverse events following immunization
  • vaccination coverage
  • vaccine hesitancy
  • pharmacovigilance
  • information systems
  • active surveillance
  • mis- and dis-information

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • Reprint: MDPI Books provides the opportunity to republish successful Special Issues in book format, both online and in print.

Further information on MDPI's Special Issue policies can be found here.

Published Papers (7 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

Jump to: Other

13 pages, 238 KiB  
Article
Vaccination Barriers in Brazil: Exploring Hesitancy, Access, and Missed Opportunities in a Cohort of Children (2017–2018)—National Vaccination Coverage Survey Results (2020–2021)
by Letícia Bezerra Faria, Ana Paula França, José Cássio de Moraes and Maria Rita Donalisio
Vaccines 2025, 13(5), 516; https://doi.org/10.3390/vaccines13050516 - 13 May 2025
Viewed by 254
Abstract
Background/Objectives: In recent years, Brazil has experienced declining vaccination coverage, raising concerns about vaccine hesitancy and barriers to access. This research analyzes the reasons for non-vaccination among children born in 2017 and 2018 in a metropolitan area of the state of São Paulo [...] Read more.
Background/Objectives: In recent years, Brazil has experienced declining vaccination coverage, raising concerns about vaccine hesitancy and barriers to access. This research analyzes the reasons for non-vaccination among children born in 2017 and 2018 in a metropolitan area of the state of São Paulo in 2020 and 2021. Methods: Data were obtained from a retrospective cohort of children born in 2017 and 2018, living in Campinas, monitored during the first 24 months by vaccination records. A stratified and clustered sample by census sector was performed according to socioeconomic conditions. The reasons for non-vaccination were obtained from interviews with the children’s guardians. Results: A total of 1775 caregivers were interviewed, and 63.1% of children had complete vaccination coverage, with lower socioeconomic groups presenting the highest rates for non-vaccination. The study identified three main groups for non-vaccination: vaccine hesitancy (e.g., fear of side effects, misinformation) in 1.7% of respondents, access difficulties (e.g., service location, financial constraints) in 7.9%, and missed opportunities (e.g., lack of vaccines, administrative barriers) in 16.4%. Conclusions: The findings indicate that the main reported barriers to childhood vaccination are missed opportunities in healthcare services, often due to vaccine shortages or administrative issues, along with social vulnerabilities. Vaccine hesitancy stems from misinformation and fear of side effects. Despite these challenges, families persist in seeking vaccination. However, coverage remains below the national targets, particularly in the second year of life. Targeted public health interventions are urgently needed to improve vaccine confidence, accessibility, and healthcare system efficiency. Full article
(This article belongs to the Special Issue Impact of Immunization Safety Monitoring on Vaccine Coverage)
14 pages, 4240 KiB  
Article
Assessing Immunization Coverage and the Negative Impact of Local Vaccine Production Cessation in Ecuador
by Esteban Ortiz-Prado, Lissette Carolina Villacreses-Brito, Jorge Vasconez-Gonzalez, Cristina Anabel Jacome, Marlon Arias-Intriago and Juan S. Izquierdo-Condoy
Vaccines 2025, 13(4), 348; https://doi.org/10.3390/vaccines13040348 - 25 Mar 2025
Viewed by 839
Abstract
Background: The COVID-19 pandemic highlighted vaccine importance while exposing inequities in global immunization, especially in LMICs like Ecuador. Local vaccine production ensures supply, reduces reliance on imports, and boosts health security. Understanding the relationship between local production and vaccination outcomes is crucial to [...] Read more.
Background: The COVID-19 pandemic highlighted vaccine importance while exposing inequities in global immunization, especially in LMICs like Ecuador. Local vaccine production ensures supply, reduces reliance on imports, and boosts health security. Understanding the relationship between local production and vaccination outcomes is crucial to addressing emerging public health challenges. Objective: The objective was to assess the impact of local vaccine production cessation on vaccination coverage rates for BCG- and DTP-containing vaccines. Methodology: This retrospective cross-sectional study analyzed vaccine coverage data from 2004 to 2023, focusing on key vaccines such as BCG and DTP, to assess the impact of the cessation of local vaccine production. Mann–Whitney U tests were conducted to compare vaccination coverage during the periods of local production (2004–2013) and post-production cessation (2014–2023). Historical context and policy implications were also evaluated to provide a comprehensive perspective. Results: A significant decline in vaccine coverage was observed following the cessation of local production. For BCG, median coverage decreased from 100% during the production period to 87.8% post-cessation (p < 0.0001). Similarly, DTP coverage dropped from a median of 99.5% to 83.4% (p < 0.0001). The findings highlight the critical role of local production in maintaining high vaccination rates and ensuring immunization equity. Conclusions: Reinvesting in local vaccine production is pivotal to improving immunization outcomes and strengthening Ecuador’s health security. International collaboration and strategic planning can help overcome current challenges, positioning Ecuador as a regional leader in vaccine production and public health resilience. Full article
(This article belongs to the Special Issue Impact of Immunization Safety Monitoring on Vaccine Coverage)
►▼ Show Figures

Figure 1

13 pages, 1435 KiB  
Article
Prevalence of Adverse Events Reported Following the First Dose of COVID-19 Vaccines in Bahia State, Brazil, from 2021 to 2022
by Ramon da Costa Saavedra, Enny S. Paixao, Maria Yury Travassos Ichihara, Maria da Conceição Nascimento Costa, Rita Carvalho-Sauer, Caroline Tianeze de Castro and Maria Gloria Teixeira
Vaccines 2025, 13(2), 161; https://doi.org/10.3390/vaccines13020161 - 7 Feb 2025
Viewed by 1044
Abstract
Background: Despite adverse events following immunization (AEFI) being well described in vaccine trials, there is a need to produce more real-world data on events supposedly attributed to vaccination against COVID-19. This study aims to estimate the prevalence of AEFI in the first [...] Read more.
Background: Despite adverse events following immunization (AEFI) being well described in vaccine trials, there is a need to produce more real-world data on events supposedly attributed to vaccination against COVID-19. This study aims to estimate the prevalence of AEFI in the first dose of COVID-19 vaccines in the state of Brazil and to verify whether such events differ among the types of vaccines offered in this country. Methods: A population-based study using linked administrative data on vaccine registry and adverse events following immunization in 2021 and 2022. The study included 10,169,378 individuals aged 18 or over who lived in Bahia and received the first dose of COVID-19 vaccines. We calculated AEFI prevalence and verified differences among vaccines by logistic regression to estimate crude and adjusted by sex and age group prevalence ratio (PR). Results: The prevalence of AEFI was 74.3 per 100,000 doses applied, with a higher rate of nonserious events, mainly following the ChAdOx1-S. More than two-thirds of these adverse effects occurred in women, and almost half were between 30 and 49 years old. The individuals who received ChAdOx1-S had a 125% higher prevalence than those who received CoronaVac. Those who received BNT162b2 and Ad26.COV2.S had a 71% and 58%, respectively, lower prevalence of AEFI than those who received CoronaVac. Conclusions: The use of vaccines against COVID-19 has proven to be positive and effective in combating SARS-CoV-2, significantly reducing morbidity and mortality from the disease. We cannot deny the presence of adverse events in the context of vaccination. However, the vaccines have proven to be safe and reliable. The results of this study offer relevant data that can contribute to the qualification of AEFI pharmacovigilance in Brazil and worldwide. Full article
(This article belongs to the Special Issue Impact of Immunization Safety Monitoring on Vaccine Coverage)
►▼ Show Figures

Figure 1

14 pages, 578 KiB  
Article
Exploring Parent-Driven Determinants of COVID-19 Vaccination in Indigenous Children: Insights from a National Survey
by Abdallah Alami, Sailly Dave, Marwa Ebrahim, Israa Zareef, Caren Uhlik and Julie Laroche
Vaccines 2025, 13(2), 132; https://doi.org/10.3390/vaccines13020132 - 28 Jan 2025
Viewed by 1026
Abstract
Background: Globally and in Canada, Indigenous populations have faced heightened vulnerability during pandemics, with historical inequities exacerbated by multigenerational colonial policies. This study aimed to identify parental factors influencing COVID-19 vaccination among Indigenous children in Canada. Methods: Data from a nationally representative, cross-sectional [...] Read more.
Background: Globally and in Canada, Indigenous populations have faced heightened vulnerability during pandemics, with historical inequities exacerbated by multigenerational colonial policies. This study aimed to identify parental factors influencing COVID-19 vaccination among Indigenous children in Canada. Methods: Data from a nationally representative, cross-sectional survey of parents/guardians with children under 18 years of age were analyzed. The study focused on Indigenous children, examining vaccine uptake, parental hesitancy, and related sociodemographic factors. Multivariable logistic regression models were employed to identify key predictors of COVID-19 vaccination. Results: COVID-19 vaccine coverage among Indigenous children was 61.8%, with higher uptake among Inuit (74.4%) children compared to Métis (61.2%) and First Nations (59.6%) children. Nearly half of Indigenous parents (53.4%) expressed hesitancy, primarily due to perceived concerns about insufficient research on the vaccine in children. Higher vaccine uptake was associated with parental education, adherence to routine vaccinations, and urban residence. Conversely, parental hesitancy, particularly related to medical concerns, significantly decreased the likelihood of vaccine uptake. Conclusions: The study highlights the complexity of vaccine hesitancy among Indigenous parents. Targeted interventions, including culturally adapted educational initiatives, community engagement, and healthcare provider advocacy, are essential to improve vaccine uptake. Full article
(This article belongs to the Special Issue Impact of Immunization Safety Monitoring on Vaccine Coverage)
►▼ Show Figures

Figure 1

15 pages, 1520 KiB  
Article
Economic and Clinical Benefits of Bivalent Respiratory Syncytial Virus Prefusion F (RSVpreF) Maternal Vaccine for Prevention of RSV in Infants: A Cost-Effectiveness Analysis for Mexico
by José Luis Huerta, Robyn Kendall, Luka Ivkovic, Carlos Molina, Amy W. Law and Diana Mendes
Vaccines 2025, 13(1), 77; https://doi.org/10.3390/vaccines13010077 - 16 Jan 2025
Viewed by 1628
Abstract
Background/Objectives: Respiratory syncytial virus (RSV) is a leading cause of respiratory infections in children. A novel RSVpreF vaccine for use among pregnant women for the prevention of RSV in infants is expected to be licensed in Mexico. Hence, the clinical and economic burden [...] Read more.
Background/Objectives: Respiratory syncytial virus (RSV) is a leading cause of respiratory infections in children. A novel RSVpreF vaccine for use among pregnant women for the prevention of RSV in infants is expected to be licensed in Mexico. Hence, the clinical and economic burden of RSV among infants in Mexico, with and without a year-round RSVpreF maternal vaccination program, was estimated. Methods: A cohort model was developed to project clinical and economic outcomes of RSV from birth to 1 year of age for maternal vaccination and no intervention. Incremental cost-effectiveness ratios were calculated from direct cost outcomes, life years, and quality-adjusted life years (QALYs). The value per dose of the RSVpreF for which the program would be cost-effective was explored. Analyses were conducted from the healthcare system perspective, with direct costs (2024 Mexican Pesos [MXN]) and outcomes discounted at 5% annually; scenario and sensitivity analyses tested the robustness of model settings and inputs. Results: Compared to no intervention, a year-round RSVpreF vaccine administered to 1891 M pregnant women would prevent 15,768 hospitalizations, 5505 emergency department cases, and 5505 physician office visits annually, averting MXN 1754 M in direct medical costs with an increase of 3402 life years or 3666 QALYs. The RSVpreF vaccine would be cost-saving up to MXN 1301/dose and cost-effective up to MXN 2105–MXN 3715/dose under an assumed cost-effectiveness threshold range of 1–3× the gross domestic product (GDP) per capita (MXN 247,310) per QALY gained. Conclusions: Year-round RSVpreF maternal vaccination would substantially reduce RSV’s clinical and economic burden among infants in Mexico and likely be a cost-effective program. Full article
(This article belongs to the Special Issue Impact of Immunization Safety Monitoring on Vaccine Coverage)
►▼ Show Figures

Figure 1

16 pages, 752 KiB  
Article
SMS-Based Active Surveillance of Adverse Events following Immunization in Children: The VigiVax Study
by Laura Augusta Gonella, Francesca Moretti, Annalisa Capuano, Caterina De Sarro, Lorenza Ferrara, Elisabetta Geninatti, Greta Guarnieri, Xhikjana Hysolakoj, Margherita Lalli, Olivia Leoni, Antea Maria Pia Mangano, Patrizia Marani Toro, Viviana Mecchia, Maria Caterina Merlano, Caterina Palleria, Anna Maria Potenza, Paola Rossi, Marco Rossi, Francesca Sanità, Ester Sapigni, Cristina Scavone, Claudia Sommaro, Marco Tuccori, Giovanna Zanoni, Ugo Moretti and VigiVax Working Groupadd Show full author list remove Hide full author list
Vaccines 2024, 12(9), 1076; https://doi.org/10.3390/vaccines12091076 - 20 Sep 2024
Viewed by 1480
Abstract
Underreporting is the main limitation of spontaneous reporting systems. This cohort-event monitoring study aims to examine the potential of short message service (SMS)-based surveillance compared to traditional surveillance systems. Using VigiVax software, parents of vaccinated children aged two years or younger, in the [...] Read more.
Underreporting is the main limitation of spontaneous reporting systems. This cohort-event monitoring study aims to examine the potential of short message service (SMS)-based surveillance compared to traditional surveillance systems. Using VigiVax software, parents of vaccinated children aged two years or younger, in the period March 2021–May 2022, received a single SMS inquiry about adverse events following immunization (AEFI). Responses were collected, validated by health operators and integrated with the information on electronic immunization registries. AEFI reports were automatically submitted to the Italian Pharmacovigilance system. Among 254,160 SMS messages sent, corresponding to 451,656 administered doses (AD), 71,643 responses were collected (28.2% response rate), and 21,231 of them (8.3%) reported AEFI. After a seriousness assessment based on clinical criteria, 50 reports (0.24%) were classified as serious. Among these, a causality assessment identified 31 reports at least potentially related to the vaccination (RR: 6.86/100,000 AD). Febrile seizures following MMRV (measles, mumps, rubella, varicella) vaccination accounted for 11 of these 31 cases, with an incidence of 32 per 100,000 AD. No fatal outcomes were reported. Our findings support the highly favorable risk profile of pediatric vaccinations and the possibility to improve spontaneous reporting through the integration of digital technologies. Full article
(This article belongs to the Special Issue Impact of Immunization Safety Monitoring on Vaccine Coverage)
►▼ Show Figures

Figure 1

Other

Jump to: Research

16 pages, 416 KiB  
Systematic Review
Postpartum Interventions to Increase Maternal Vaccination Uptake: Is It Worth It?
by Eleni Konstantinou, Sofia Benou, Eleftheria Hatzidaki, Aggeliki Vervenioti, Gabriel Dimitriou, Vassiliki Papaevangelou, Christine E. Jones and Despoina Gkentzi
Vaccines 2024, 12(10), 1130; https://doi.org/10.3390/vaccines12101130 - 1 Oct 2024
Viewed by 1364
Abstract
Background/Objectives: Vaccination of pregnant and postpartum women for pertussis, influenza and COVID-19 not only protects themselves but also offspring. Despite the benefits of this approach, vaccination uptake remains suboptimal in pregnancy. Where the opportunity to be vaccinated in pregnancy is missed, the offer [...] Read more.
Background/Objectives: Vaccination of pregnant and postpartum women for pertussis, influenza and COVID-19 not only protects themselves but also offspring. Despite the benefits of this approach, vaccination uptake remains suboptimal in pregnancy. Where the opportunity to be vaccinated in pregnancy is missed, the offer of vaccination in the post-partum period may be an alternative strategy. The aim of this systematic review is to assess the impact of interventions to increase vaccination uptake in the postpartum period on vaccination uptake. Methods: A literature search was performed in MEDLINE, including interventional studies promoting vaccination uptake in postpartum women published between 2009 and 2024. The search was conducted according to PRISMA guidelines and registered with PROSPERO. Results: We finally included 16 studies in the review, and the primary outcome was vaccination uptake in the postpartum period. The most significant factors for increasing uptake were recommendation from healthcare providers, type of interventions used, and delivery of vaccines in the maternity wards or the community. Conclusions: In conclusion, maternal vaccination rates in the postpartum period may increase with targeted education by healthcare professionals and positive reinforcement. The interventions described in these studies could be applied in the healthcare systems worldwide. Full article
(This article belongs to the Special Issue Impact of Immunization Safety Monitoring on Vaccine Coverage)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-7
Back to TopTop