Routine Vaccination Research Articles

Abstract A143: The development of a risk prediction model to predict patients’ likelihood of completing human papillomavirus vaccination

Abstract Background: Human Papillomavirus (HPV) cancers can be preventable if HPV vaccination is received in adolescents before the age of 13, yet only 55% of Oregonian adolescents had an HPV series completion in 2020.2 The recommended vaccination age for HPV recently dropped to age 9. This new recommended age allows providers to offer HPV vaccination with routine vaccinations. To further increase HPV vaccination rates, research is critically needed on new interventions to promote vaccination among vaccine resistant groups, and populations that are most in need of targeted interventions. We assessed patterns in vaccination from 2015-2022, in preparation of the development of a prognostic risk prediction model to identify patients’ likelihood of obtaining HPV vaccination. Methods: We used a retrospective cohort from a large health system to assess vaccination patterns from 2015-2022. Eligible patients were members of Kaiser Permanente Northwest, 9-18 years old, and did not have a history of adverse vaccination outcomes. We assessed vaccination initiation, completion by age, gender and year. Results: Among 29,398 eligible patients, 44.3% had no vaccination, 14.5% had one dose, and 41.2% had completed the series. More patients were vaccinating at earlier ages from 2015-2022. Of those with one dose or who had completed the series, 84% had vaccinated by the age of 12 in 2022 compared to 74% in 2015. The change was greater in boys with 70.5% before age 12 in 2015 compared with 84% in 2022. ConclusionsWhile efforts to increase HPV vaccination and initiate at younger ages have been successful, efforts need to be targeted to specific populations. The patterns of HPV vaccination over the past 7 years highlights improvement, but system level interventions may be needed to adequately increase vaccination among resistant populations. This presentation will discuss the assessment of vaccination patterns in preparation of the development of a prognostic risk prediction model and describe how the model will be used in a system to target populations for early interventions to complete vaccination. Citation Format: Amanda A. Petrik, Matthew Slaugher, Gloria Coronado, Eric Johnson. The development of a risk prediction model to predict patients’ likelihood of completing human papillomavirus vaccination [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A143.

Abstract A162: The influence of parental barriers to healthcare on adolescent HPV vaccination uptake and completion among Latinos in Los Angeles

Abstract Objective: This study aims to investigate the association between parental barriers to healthcare access and HPV vaccination uptake among Latino adolescents in Los Angeles. Background: Human papillomavirus (HPV) induced cervical cancer (CC) remains a significant public health concern. Routine HPV vaccination has been recommended in the United States for girls since 2006 and boys since 2011 yet disparities in vaccine initiation and completion persist, particularly among Latino adolescents in Los Angeles. Methods: This cross-sectional study analyzed child data provided by mothers recruited from the Es Tiempo campaign (2016-2018). A total of 353 Latino adolescents aged 9 to 26 years were included in the sample. We used crosstabs to assess vaccine initiation and completion differences by child sex and birth order, while logistic regression models were used to evaluate the association between parental barriers to healthcare, such as lack of health insurance and access to a primary care provider (PCP), and HPV vaccination initiation. Results: Among the sample, 44% initiated the HPV vaccine, and 23% completed the series, with significantly higher rates among girls and firstborn children. Regarding barriers, lack of health insurance was associated with decreased odds of HPV vaccination uptake while access to a PCP showed a slight increase in vaccination uptake odds. Conclusion: HPV vaccination uptake among Latino adolescents in Los Angeles remains suboptimal, with disparities observed by gender and birth order. To improve public health outcomes, targeted interventions are needed to increase HPV vaccination uptake among Latino adolescent boys, and further research is needed to understand vaccine adherence patterns within families and among siblings. Moreover, while parental barriers to healthcare may influence vaccination uptake, future studies should also explore how factors like parental education level and socioeconomic status influence HPV vaccination status in combination with access barriers. Citation Format: Anju F. Kane, Lourdes Baezconde-Garbanati. The influence of parental barriers to healthcare on adolescent HPV vaccination uptake and completion among Latinos in Los Angeles [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A162.

Vaccine hesitancy among parents of children in their first two years of life.

Vaccine hesitancy is considered a primary cause of outbreaks of vaccine-preventable infectious diseases. The Austrian vaccination plan includes 24 vaccinations in the first 2 years of life, 12 for free and 12 subject to a fee. Since preterm babies are more susceptible to severe infections, immunization is a vital protection strategy. This study examines the routine immunization schedule recommended for children in Austria, the number of timely vaccinations, and the number of delayed and rejected vaccinations. Possible reasons for vaccination delays and rejection and potential influencing factors (preterm birth, COVID-19 pandemic, information sources) are also analyzed. We included children aged 2 to 5 years who presented to Vienna's largest pediatric center with an Austrian mother-child pass and spent the first 2 years of their lives in Austria. Data was collected using questionnaires about the vaccination status, parents' reasons for any rejections or delays in the recommended vaccination regimen, the impact of the COVID-19 pandemic on individuals' vaccination behavior, and child-specific influencing factors such as preterm birth and socioeconomic factors. 90% of the 150 study subjects follow the recommendations on routine vaccinations, while 40-62% accept vaccinations subject to a fee. Preterm infants received less fee-based (53%) as well as gratuitous (88%) vaccinations. While free vaccinations tend to be delayed, more fee based vaccinations are rejected. With free vaccinations, delays and refusals occur due to illness or missed appointments. In the case of fee- required vaccinations, however, fears of side effects are also one of the main reasons. Due to the COVID-19 pandemic, about a quarter of parents have become more skeptical about vaccines. However, the vaccination rate of premature babies is usually just below that of full-term babies. Physicians remain the most trustworthy source of information about vaccinations. Free vaccinations are more accepted by parents than fee based vaccinations. Preterm babies, which are a high risk group for vaccination preventable diseases, show a lower or delayed vaccination rate, which must be prevented through intensive doctor education. In addition, vaccination hesitancy changed during the COVID-19 pandemic, which needs to be addressed during the medical consultation.

An Application of an Initial Full Value of Vaccine Assessment Methodology to Measles-Rubella MAPs for Use in Low- and Middle-Income Countries.

Measles and rubella micro-array patches (MR-MAPs) are a promising innovation to address limitations of the current needle and syringe (N&S) presentation due to their single-dose presentation, ease of use, and improved thermostability. To direct and accelerate further research and interventions, an initial full value vaccine assessment (iFVVA) was initiated prior to MR-MAPs entering phase I trials to quantify their value and identify key data gaps and challenges. The iFVVA utilized a mixed-methods approach with rapid assessment of literature, stakeholder interviews and surveys, and quantitative data analyses to (i) assess global need for improved MR vaccines and how MR-MAPs could address MR problem statements; (ii) estimate costs and benefits of MR-MAPs; (iii) identify the best pathway from development to delivery; and (iv) identify outstanding areas of need where stakeholder intervention can be helpful. These analyses found that if MR-MAPs are broadly deployed, they can potentially reach an additional 80 million children compared to the N&S presentation between 2030-2040. MR-MAPs can avert up to 37 million measles cases, 400,000 measles deaths, and 26 million disability-adjusted life years (DALYs). MR-MAPs with the most optimal product characteristics of low price, controlled temperature chain (CTC) properties, and small cold chain volumes were shown to be cost saving for routine immunization (RI) in low- and middle-income countries (LMICs) compared to N&S. Uncertainties about price and future vaccine coverage impact the potential cost-effectiveness of introducing MR-MAPs in LMICs, indicating that it could be cost-effective in 16-81% of LMICs. Furthermore, this iFVVA highlighted the importance of upfront donor investment in manufacturing set-up and clinical studies and the critical influence of an appropriate price to ensure country and manufacturer financial sustainability. To ensure that MR-MAPs achieve the greatest public health benefit, MAP developers, vaccine manufacturers, donors, financiers, and policy- and decision-makers will need close collaboration and open communications.

Prevalence and Trends of Not Receiving a Dose of DPT-Containing Vaccine Among Children 12–35 Months: An Analysis of 81 Low- And Middle-Income Countries

AbstractNot receiving a DPT-containing vaccine in early childhood indicates an absence of routine immunization, which puts children at an elevated risk of mortality, morbidity, and worse human development over the life course. We estimated the percentage of children 12–35 months who did not receive a dose of DPT-containing vaccine (termed zero-dose children) using household surveys from 81 low- and middle-income countries conducted between 2014 and 2023. For 68 countries with more than one survey (with the earlier survey conducted 2000–2013), we estimated the average annual percentage point change in prevalence of zero-dose children between the earliest and latest surveys. We also explored the association of zero-dose prevalence with postneonatal and child mortality, health expenditure, and Gavi-eligibility. Overall, 16% of children in our pooled sample had not received a dose of DPT-containing vaccine. There was a 0.8% point decline in zero-dose prevalence per year on average across the period studied. A single percentage point average annual decline in zero-dose prevalence was associated with an average annual decrease of 1.4 deaths in the postneonatal and childhood period per 1000 live births. Gavi-eligible countries had a much faster decline in zero-dose prevalence than other countries. Large gains have been made in reducing the percentage of children who did not receive a DPT-containing vaccine. Efforts to reduce the number of zero-dose children should focus on countries with high prevalence to achieve the Immunization Agenda 2030. Healthcare spending could be prioritized so that the prevalence of zero-dose children is reduced.

Vaccination Across the Lifespan: A Public Health Imperative

Vaccination is an essential public health intervention, preventing infectious diseases, saving millions of lives globally, and reducing the burden on the healthcare system. Currently, vaccines prevent between 3.5 and 5 million deaths annually from diseases like diphtheria, tetanus, pertussis, influenza, and measles.1 It not only protects individuals but also contributes to herd immunity, safeguarding entire communities. Maintaining high vaccination coverage across all age groups reduces the burden of preventable illnesses and safeguards public health. Childhood immunization is a cornerstone of preventive healthcare, providing protection against various life-threatening diseases during the most vulnerable years of life. Key vaccines include the DTP, MMR, IPV, Hib, and pneumococcal. 2 Global immunization coverage has stagnated since 2022, with 14.5 million children missing all DTP doses and 6.5 million not completing follow-up doses. There is an urgent need for innovative solutions to meet the Immunization Agenda 2030 targets of 90% vaccination coverage. 3 Vaccination has a pivotal role in women's healthcare, especially during pregnancy. The CDC recommends the inactivated flu and Tdap vaccines for protection of both mother and baby, with the flu vaccine best administered by the end of October and Tdap between 27 and 36 weeks of gestation. The HPV vaccine is recommended for girls aged 9–14 (two doses) and women over 14 (three doses) to protect against cervical cancer and genital warts, but it should not be given during pregnancy due to insufficient safety data.4 Regular vaccinations are crucial for adults aged 50–64, including COVID-19, influenza, shingles, and Tdap/Td. Hepatitis B is recommended for those up to 59 years old, and MMR for those born in 1957 or later. For those 65 and older, COVID-19, influenza, pneumococcal, and shingles vaccines are essential, with an RSV recommended. Healthcare providers should be consulted to determine additional vaccines for older adults, as regular vaccinations are important to prevent serious health issues due to immune decline and chronic conditions. 5 A comprehensive vaccination strategy is important for community health, encompassing children, women, adults, and older adults. A strong public health infrastructure that guarantees vaccine access and affordability should serve as the foundation for this strategy. In order to improve vaccination coverage, public awareness campaigns must be customized to address the concerns of all age groups. Children's immunization programs must be implemented in schools and coincide with routine physical examinations while women, particularly those who are of reproductive age, require special attention. Adult immunization programs must to prioritize occupational health, and older people need to remain updated. Considering immunization as a top public health priority, policy makers and healthcare professionals must work together to ensure continuous monitoring and evaluation of vaccination campaign’s coverage and effectiveness in order to spot gaps and launch prompt interventions.

Qualitative assessment of the enablers and barriers of COVID-19 vaccination integration, into routine immunization Programme at primary health care facilities in Ekiti state, Nigeria

BackgroundThe introduction of the COVID-19 vaccine influenced discussions to explore integrating COVID-19 vaccination into routine immunization (RI) programs. Subsequently, the WHO Strategic Advisory Group Experts (SAGE) on immunization plausibly advised countries to leverage the COVID-19 vaccination rollout as a transformative opportunity to establish a resilient immunization system, through an integrated immunization system, resulting in strengthened primary healthcare services.ObjectiveThis study assessed the enablers and barriers to integrating COVID-19 vaccination into the routine immunization programme in Ekiti state, Nigeria.MethodsThis study utilized a qualitative research approach to obtain information from 40 participants selected purposively across the primary healthcare facilities, LGA, and state levels. A three-tier approach was employed to select the LGAs. At the same time, In-depth interviews were conducted to elicit relevant information on the assessment of enablers and barriers to integrating COVID-19 vaccination into routine immunization through an interview guide. All the audio interview files were transcribed into English Language, coded, and presented using a thematic approach.ResultsA total of 40 healthcare workers across Ekiti state were selected to participate in this study. Our study found the enablers of integrating COVID-19 into routine immunization to include demand generation and social mobilization, health education, health workers training, data validation, financing, and supervision. However, rumors, demand for incentives, Adverse Events Following Immunization (AEFI), manpower shortage, poor internet network services, and bad road networks were reported as barriers to integrating COVID-19 vaccination into routine immunization in Ekiti state.ConclusionWhile the enablers of integrating COVID-19 vaccination into routine immunization may outweigh its barriers, it is pertinent to know that the efforts towards integrating COVID–19 vaccination in the RI Program is a call to all stakeholders to ensure sustainability. The identified barriers in the study must be addressed to ensure a strengthened health system. Therefore, achieving a successful integration and uptake of vaccination/immunization is anchored on driving demand generation, social mobilization, health education, availability of healthcare workers, integrated supervision, and financing.

Progress with the Second Dose Measles Vaccine Introduction and Coverage in the WHO African Region.

To achieve global and regional measles elimination objectives, the World Health Organization (WHO) recommends coverage of 95% or higher with two doses of measles-containing vaccine. A second dose of measles-containing vaccine (MCV) is typically administered in the second year of life after 12 months of age. We reviewed WHO-UNICEF estimates of national coverage (WUENIC) for the first and second doses of MCV (MCV1 and MCV2, respectively) and calculated drop-out rates between MCV1 and MCV2 for countries in the WHO African Region. From 2013 to 2023, estimated regional MCV2 coverage increased from 7% to 49%, and at the end of 2023, 43 (91%) countries had introduced MCV2 into their routine immunization programs. Countries with more antigens provided in the second year of life had higher mean and median MCV2 coverage levels, and lower drop-out rates between MCV1 and MCV2, as compared to countries providing only MCV2. Despite substantial progress, MCV2 coverage remains below the required levels to achieve and sustain elimination, and many countries have high drop-out rates between MCV1 and MCV2 coverage, indicating challenges in reaching children over 12 months of age. Increasing coverage of MCV2 and other vaccines in the second year of life is essential to achieving higher and equitable routine immunization coverage. This will require continued efforts to understand and mitigate barriers to reaching children after 12 months of age and accelerated implementation of available tools.

“Build back the confidence”: qualitative exploration of community experiences with polio vaccination in the Covid-19 context in Cameroon and Ethiopia

BackgroundIn 2020, as the Global Polio Eradication Initiative worked to address outbreaks of vaccine-derived poliovirus Type 2, particularly in sub-Saharan Africa, the Covid-19 pandemic suspended routine immunization campaigns worldwide. There were concerns about how Covid-19 – and the introduction of Covid-19 vaccines – might influence uptake of the oral polio vaccine (OPV). To inform communications strategies, we conducted a qualitative study to explore insights from community stakeholders into how Covid-19 influenced perceptions of OPV and vaccination campaigns.MethodsWe conducted 32 focus group discussions with caregivers of children under 5 and polio frontline workers as well as 22 in-depth interviews with healthcare practitioners and social influencers in Cameroon and Ethiopia. In each country, we purposively sampled stakeholders per discrete eligibility criteria from one urban (Yaoundé and Addis Ababa) and one peri-urban site (Bafia and Adama).ResultsWe found that the Covid-19 pandemic and related precautionary measures introduced new challenges for OPV campaigns in Cameroon and Ethiopia, including reduced caregiver confidence in routine immunizations and an erosion of trust between caregivers and frontline workers. A salient concern among caregivers was that Covid-19 vaccines might be delivered in place of OPV. When asked how to maximize community support for future OPV campaigns, stakeholders suggested to rebuild caregiver trust for frontline workers; use a variety of information sources to ensure consistent messaging on vaccination reaches caregivers in a timely manner; increase remuneration, resources, and training for frontline workers; and leverage existing community influencers and groups.ConclusionsDespite the challenges to vaccination campaigns experienced during the Covid-19 pandemic, it was anticipated that the Polio Programme would continue to experience community support for OPV with appropriate messaging and community coordination. These efforts would “build back the confidence” among caregivers and other community stakeholders regarding community-based vaccination campaigns. Social and behavior change approaches that leverage clear, consistent messaging from multiple trusted platforms could address caregiver trust and dismantle mis/dis-information that creates confusion surrounding vaccines.

Zero-dose children in Latin America: analysis of the problem and possible solutions

Introduction Zero-dose children (ZDC) are defined as those that have never been reached by routine immunization services. In Latin America, almost 2.7 million infants younger than 1 year of age, have incomplete vaccination schedules, and vaccine preventable diseases such as measles or polio have increase worldwide. ZDC are reported to reside in high risk and fragile settings, including remote-rural areas, urban slums, and conflict-affected areas. Identifying the problem and settings in each country is mandatory to propose possible solutions to the immunization coverage situation. Areas covered In November 2023, a group of experts of the Latin America Society of Pediatric Infectious Diseases (SLIPE) analyzed the global and regional reality of ZDC, and present in this document an updated reality of the Latin American region and the weight of the possible interventions to overcome this problem. Expert commentary Communication is a key element to improve vaccination coverage, as it is quality and use of vaccination data. Campaigns that deliver targeted and effective messages to communities and families, provide education about vaccination, avoid missed vaccination opportunities, and coordinate efforts across different sectors and communities, among other strategies, could improve the current immunization situation.

Impact of the COVID-19 Pandemic on Measles Vaccination Coverage and Estimated Catch-up Efforts for Serbia.

Measles is highly infectious, requiring ≥95% vaccine coverage rate (VCR) to prevent outbreaks. This study aimed to understand the impact of the COVID-19 pandemic on routine measles-containing vaccine (MCV) VCRs in Serbia and estimate national and regional catch-up vaccination required to prevent outbreaks. A multiplier model was used to calculate annual MCV dose 1 (MCV1) and MCV dose 2 (MCV2) VCRs for children 1-6 and 6-12 years of age, respectively, for 2011-2022. Postpandemic (2023-2024) VCRs were modeled. The numbers of administered doses were compared to prepandemic and postpandemic, and monthly catch-up rates were calculated for 12-, 18- and 24-month campaigns. Between prepandemic and pandemic periods, national MCV1 VCR decreased from 88% to 81%, while MCV2 VCR decreased from 92% to 89%, corresponding to 20,856 missed MCV1 and 8760 missed MCV2 doses. Assuming national VCRs returned to prepandemic levels post-2022, 18% of children 1-6 years of age and 11% of children 6-12 years of age would have missed their MCV1 and MCV2 doses, respectively, by 2024. To catch up missed doses under this scenario, most regions would require monthly catch-up rates of 25%, 16% or 12% for MCV1 and 14%, 9% or 7% for MCV2, considering 12-, 18- or 24-month campaigns, respectively. The pandemic negatively impacted MCV VCRs in Serbia, leaving a sizeable proportion of children with missed doses. Significant catch-up efforts are required to recover VCRs to prepandemic levels and avoid future measles outbreaks, with increased monthly administration rates versus those in prepandemic periods.

Study on Trend of Immunization Coverage in Mutum Biyu Ward "B" From 2016-2019 in Gassol Local Government Area, Taraba State, Nigeria

This study examines the trend of immunisation coverage for Bacille Calmette-Guerin (BCG), Oral Polio Vaccine (OPV), Measles, and Yellow Fever in Mutum Biyu Ward 'B' of Gassol local Government Area, Taraba State, Nigeria, from 2016 to 2019. The DHIS2 Nigeria platform was used to gather secondary data using a quantitative, cross-sectional approach. In order to analyse the completion and non-completion rates of Routine Immunisation (RI) schedules, vaccination cards and carer recollection were the main sources of immunisation histories. One-way ANOVA testing and descriptive statistics were used in the data analysis. The study's findings showed that vaccination coverage varied over time. The BCG coverage saw notable fluctuations, peaking in the years 2017 and 2019. In 2018, OPV coverage rose on average but somewhat decreased. Measles vaccination rates were steady at first, then they fell in 20l8 and then sharply recovered in 2019. The vaccination rate for yellow fever was low in 20l6, improved slightly in 2017, declined sharply in 2018, and then reached its peak in 2019. The study recommended localized use of geo-mapping to identify and map communities with low immunisation coverage in Mutum Biyu Ward "B" of Gassol LGA, Taraba State.

False-Positive Human Immunodeficiency Virus-1 Test Results With Rapid Seroreversion After Third-Trimester Tdap Booster Vaccination.

False-positive and false-negative results in human immunodeficiency virus (HIV) testing are expected at some frequency. False-positive results have been reported in association with various conditions, including pregnancy, autoimmune disease, and infection. We present an atypical case of a pregnant patient receiving false-positive HIV results for both screening and antibody confirmatory tests after a recent routine vaccination. A 34-year-old woman, G4P1021, with a negative first-trimester HIV test result received a tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) booster at 35 2/7 weeks of gestation. Test results at 36 2/7 weeks of gestation were positive in both HIV-1/2 antigen-antibody screening and a confirmatory HIV-1 antibody differentiation immunoassay, but follow-up test results at 36 5/7 weeks and later were negative. Repeat testing and erythrocyte typing confirmed that this was not a result of laboratory error or specimen mishandling. HIV antiretroviral therapy was started and was later discontinued. A scheduled primary cesarean delivery performed at 39 1/7 weeks of gestation due to breech presentation was uncomplicated. False-positive results in HIV screen and confirmation testing were associated with receipt of a Tdap vaccine booster 7 days prior. This test result pattern is similar to that seen very rarely in previous cases, and the rapid seroreversion to negative suggests an acute immunologic trigger leading to a falsely reactive antibody. Clinicians should be aware of the potential for false-positive HIV test results in patients who recently received vaccination or with other immune triggers and retest at a short interval if suspected.

Cost-Effectiveness Analysis of Routine Childhood Immunization with 20-Valent versus 15-Valent Pneumococcal Conjugate Vaccines in Germany.

This study aimed to evaluate the cost-effectiveness of routine childhood immunization with the 20-valent pneumococcal conjugate vaccine (PCV20) in a four-dose regimen (3 + 1 schedule) versus the 15-valent PCV (PCV15/V114) in a three-dose regimen (2 + 1) in Germany. The study utilized a decision-analytic Markov model to estimate lifetime costs and effectiveness outcomes for a single birth cohort in Germany. The model tracked the incidence of acute pneumococcal infections and long-term pneumococcal meningitis sequelae for both vaccination strategies. The vaccine effectiveness data were derived from published clinical trials and observational studies of PCV7 and PCV13. Indirect effects, such as herd protection and serotype replacement, were included in the model. The model adopted a societal perspective, including direct medical, direct non-medical, and indirect costs. Scenario and sensitivity analyses were performed. In the base case, PCV20 prevented more pneumococcal disease cases and deaths, with an expected gain of 96 quality-adjusted life years (QALYs) compared to V114. However, PCV20 was associated with a total incremental cost of EUR 48,358,424, resulting in an incremental cost-effectiveness ratio (ICER) of EUR 503,620/QALY. Most of the scenario and sensitivity analyses estimated that the ICER for PCV20 exceeded EUR 150,000/QALY. Routine childhood immunization with PCV20 instead of V114 may not be an economically efficient use of healthcare resources in Germany.

Analysis of health claims data on vaccination coverage in older adults in Bavaria, Germany: Influenza, pneumococcus and herpes zoster

BackgroundVaccination is essential, especially in older adults whose immune system function declines with age. The COVID-19 pandemic and its associated lockdowns temporarily disrupted routine vaccination services. We aimed to assess vaccination coverage for Influenza, Pneumococcus, and Herpes zoster among older adults in Bavaria over time and investigate potential pandemic effects on these rates. MethodsBased on health claims data from the Bavarian Association of Statutory Health Insurance Physicians (KVB), we estimated the percentage of adults aged 60 years and older vaccinated following the German Standing Committee on Vaccinations (STIKO) recommendation for Influenza (2012−2021), Pneumococcus (2017–2021) and Herpes zoster (2019–2021), stratified by sex and 10-year age groups. Using time series regression analysis, we estimated the effect of the pandemic period (2020−2021) on quarterly Influenza and Pneumococcal vaccination rates. ResultsIn the first year of the pandemic (2020), Influenza, Pneumococcus and Herpes zoster coverage in both sexes increased by 9.9, 8.7, and 2.5 percentage points (pp), respectively. In 2021, Influenza coverage decreased by 4.7 pp., while Pneumococcus and Herpes zoster coverage increased by 2.7 and 3.8 pp., respectively. Influenza and Pneumococcal vaccinations showed a seasonal pattern, with vaccinations occurring mainly in the fourth quarter; this pattern was distorted for Pneumococcus during the pandemic. Per the time series regression analysis, Influenza vaccination rates in the fourth quarters of 2020 and 2021 were 7.86 (95 %CI: 5.10–10.62) and 8.87 (95 %CI: 5.80–11.54) pp. higher for males and females, respectively, compared to that of the pre-pandemic period. During the pandemic, the quarterly Pneumococcal vaccination rates increased by 0.68 (95 %CI: 0.19–1.18) pp. in males and 0.80 (95 %CI: 0.30–1.30) pp. in females. ConclusionThe heightened increase in vaccination rates observed in 2020 may have resulted from increased vaccination awareness during the pandemic. As the pandemic effect wanes, more efforts are needed to sustain and increase these vaccination rates.

Governance matters: Exploring the impact of governance on routine immunization performance in 54 African countries: A 10-year (2012−2021) analysis using linear mixed models

BackgroundImmunization coverage across numerous African nations has, unfortunately, shown little improvement and, in some cases, has even decreased over the past decade, leaving millions of children vulnerable to vaccine-preventable diseases. While efforts to improve immunization performance have primarily focused on the health system, effective delivery of immunization services is intricately linked to a country's governance, which, in this context, reflects a government's ability to provide comprehensive services to its citizens. This study investigated the relationship between governance, measured using the Mo Ibrahim Index for African Governance, and the trajectory of immunization coverage for three vaccines in 54 African countries from 2012 to 2021. MethodsWe conducted an ecological study utilizing publicly available datasets, the WHO/UNICEF estimates of National Immunization Coverage and the Ibrahim Index of African Governance score (IIAG). We described the trends in routine immunization performance, evaluated and assessed the impact of governance on immunization coverage across 54 African countries for the period 2012 to 2021, using linear mixed models and focusing on three vaccines provided through the Expanded Program on Immunization (DTPCV1, DTPCV3, and MCV1). ResultsAmong the 54 African countries studied, 32 (59.3 %) witnessed an overall decrease (slope of change in immunization coverage over time < 0) in immunization coverage, with 16 (29.6 %) experiencing a significant decline (slope of change significantly different from zero (P < 0.05)) in coverage. For DTPCV3, 31 countries (57.4 %) demonstrated a decline in coverage, with 12 (22.2 %) being significant declines. Thirty-two countries (59.2 %) reported a decrease in MCV1 coverage over the analysis period, with 17 (31.5 %) significant. Across all three antigens, the IIAG overall score was positively associated with immunization coverage over time. One unit increase in the IIAG score correlated with an average annual increase of 0.64 (95 % CI: 0.35–0.93) percentage points in DTPCV1 coverage, 0.74 percentage points (95 % CI: 0.42–1.07) in DTPCV3 coverage, and 0.60 (95 % CI: 0.30–0.91) percentage points in MCV1 coverage. These findings suggest that an African country with an average IIAG score just one unit higher than their observed average value over the study period, would have achieved a 6.4 %, 7.4 %, and 6.0 % coverage for DTPCV1, DTPCV3, and MCV1, respectively, above its 2021 coverage levels. ConclusionThe Expanded Program on Immunization aspires to reach all eligible populations with life-saving vaccines, regardless of the context. We found that country governance may be an important determinant of immunization performance, potentially explaining the observed stagnation or decline in immunization performance and the heightened vulnerability of immunization programs to external shocks. Understanding the nexus between governance and service delivery suggests that immunization actors, funders, and other stakeholders may need to adjust their expectations of countries' immunization performance accordingly.

Don't wait, vaccinate: evaluation of routine vaccination administration and reactogenicity in preterm infants.

To evaluate the incidence of cardiorespiratory events in preterm infants when administering the 2-month vaccine series all at once compared to spreading vaccines over multiple days. This single-center, retrospective cohort study from 2019-2022 included preterm neonates receiving 2-month vaccinations. The primary outcome was incidence of cardiorespiratory events from time of initial vaccine administration up to 48 h after final administration. Univariate analysis was performed to identify predictors of primary outcome. There were 127 patients (pre-practice change n1 = 52, post-practice change n2 = 75) included with no difference in the number of cardiorespiratory events between groups. Predictors of severe event included younger gestational age, smaller birth weight, shorter birth length, and greater cardiorespiratory events at baseline. Vaccine schedule interruptions occur more often when administration is spread over multiple days. Administration of 2-month vaccinations all at once was not associated with increased cardiorespiratory events and prevents interruptions to vaccine schedule.

The Improvement of Adaptive Immune Responses towards COVID-19 Following Diphtheria-Tetanus-Pertussis and SARS-CoV-2 Vaccinations in Indonesian Children: Exploring the Roles of Heterologous Immunity.

Routine childhood vaccination, e.g., for diphtheria, tetanus, and pertussis (DTP), might provide additional protection against SARS-CoV-2 infection. This concept of heterologous immunity was explored in healthy children receiving both DTP and inactivated SARS-CoV-2 vaccines. A cross-sectional study was performed on 154 healthy children aged 6-8 years old in Jakarta, Indonesia. Their vaccination status for the DTP (including a diphtheria-tetanus booster vaccine at 5 years old) and CoronaVac (from 6 years old) vaccines were recorded. Peripheral blood samples were collected from all participants, in which anti-diphtheria toxoid IgG and anti-SARS-CoV-2 S-RBD antibodies and T cell-derived IFN-γ were measured. The study participants with complete DTP vaccination had significantly higher titers of anti-diphtheria toxoid IgG than the ones without (median = 0.9349 versus 0.2113 IU/mL; p < 0.0001). Upon stratification based on DTP and CoronaVac vaccination statuses, the participants with complete DTP and CoronaVac vaccinations had the highest titer of anti-SARS-CoV-2 S-RBD antibodies (median = 1196 U/mL) and the highest concentration of SARS-CoV-2-specific T cell-derived IFN-γ (median = 560.9 mIU/mL) among all the groups. Healthy children aged 6-8 years old with complete DTP and CoronaVac vaccinations exhibited stronger SARS-CoV-2-specific T cell immune responses. This might suggest an additional benefit of routine childhood vaccination in generating protection against novel pathogens, presumably via heterologous immunity.

Pertussis Epidemiology in Children: The Role of Maternal Immunization.

In the last twelve months, a significant global increase in pertussis cases has been observed, particularly among infants under three months of age. This age group is at the highest risk for severe disease, hospitalization, and death. Maternal immunization with the Tdap vaccine during pregnancy has been recommended to protect newborns by transferring maternal antibodies transplacentally. This review examines the current epidemiology of pertussis, the importance of preventing it in young children, and the effectiveness of maternal immunization. Despite the proven benefits of maternal vaccination, which has been found effective in pertussis prevention in up to 90% of cases, coverage remains suboptimal in many countries. Factors contributing to low vaccination rates include vaccine hesitancy due to low trust in health authority assessments, safety concerns, practical barriers to vaccine access, and the impact of the COVID-19 pandemic, which disrupted routine vaccination services. The recent increase in pertussis cases may also be influenced by the natural cyclic nature of the disease, increased Bordetella pertussis (Bp) activity in older children and adults, and the genetic divergence of circulating Bp strains from vaccine antigens. Given the high efficacy of maternal vaccination in preventing pertussis in infants, increasing coverage rates is crucial. Efforts to improve vaccine uptake should address barriers to access and vaccine hesitancy, ensuring consistent immune protection for the youngest and most vulnerable populations. Enhanced maternal vaccination could significantly reduce the incidence of whooping cough in infants, decreasing related hospitalizations and deaths.

Pediatric Varicella-related Hospitalization in Turkey Between 2008 and 2018: Impact of Universal Single Dose Varicella Vaccine (VARICOMP Study).

A single-dose varicella vaccine at 12 months of age was introduced to the National Immunization Program in February 2013 in Turkey. This study aimed to evaluate varicella-related hospitalization in children and the impact of a single-dose live attenuated varicella vaccine over the first 5.5 years of introducing a universal varicella vaccination. We analyzed data collected from the medical records of children <18 years old who required hospitalization due to varicella in 17 cities representing 50% of the childhood population in Turkey between 2008 and 2018. We calculated the rate of hospitalization for varicella per 100,000 children during the study period. The main objective of this study was to determine the yearly rate of hospitalization due to varicella and to compare these rates in the pre-vaccine and post-vaccine periods. The secondary objective was to compare demographic features, varicella-related complications, and outcomes between the pre-vaccine and post-vaccine periods. A total of 4373 children (2458 boys and 1915 girls; 72.3% previously healthy) were hospitalized for varicella over a 10-year period, including 2139 children during the pre-vaccine period and 2234 children during the post-vaccine period. Overall, varicella hospitalization rates decreased significantly after the introduction of varicella vaccination [pre-vaccine vs. post-vaccine period; 3.79 vs. 2.87 per 100,000 per year; P < 0.001; odds ratio 0.75; 95% confidence interval 0.64-0.88]. The incidence of varicella-related hospitalization among children between 1 and 5 years of age was significantly lower in the post-vaccine era than in the pre-vaccine era, with a 60.2% decrease in hospitalizations (2.43 vs. 6.12 per 100,000 children; P < 0.001, odds ratio 0.39; 95% confidence interval 0.34-0.46). In both the <1-year and 6- to 10-year age groups, the incidence of varicella-related hospitalizations was similar in the pre-vaccine and post-vaccine periods. The incidence of varicella-related hospitalization was higher in the post-vaccine era among 11-15 years and >15-year-old groups (P < 0.01 and P < 0.05). The mean age was higher during the post-vaccine period than during the pre-vaccine period (P < 0.001). The absolute number of secondary bacterial infections (P < 0.01), respiratory complications (P < 0.01), and neurological complications (P < 0.001) was significantly lower during the post-vaccine period. The incidence of severe varicella was lower during the post-vaccine period than during the pre-vaccine period (P < 0.001). After 5.5 years of routine single-dose varicella vaccine use, we observed the impact of varicella vaccination on the incidence of varicella-related hospitalizations, especially in the target age group. However, we did not observe herd protection in the other age groups. The implementation of a second dose of the varicella vaccine in the National Immunization Program would help control disease activity.