Respiratory syncytial virus vaccination during pregnancy for improving infant outcomes.

Background: Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections (LRTIs) in infants. Maternal RSV vaccination is a preventive strategy of great interest, as it could have a substantial impact on infant RSV disease burden. In recent years, the clinical development of maternal RSV vaccines has advanced rapidly.

Are maternal vaccines effective and safe for mothers and infants? A systematic review and meta-analysis of randomised controlled trials.

Introduction: Maternal vaccination is a promising strategy to reduce the burden of vaccine-preventable diseases for mothers and infants. We aimed to provide an up-to-date overview of the efficacy and safety of all available maternal vaccines.

Methods: We searched PubMed, Embase, CENTRAL and ClinicalTrials.

Socio-psychological determinants of second trimester maternal pertussis vaccination acceptance in the Netherlands.

Background: A maternal tetanus-diphtheria-and-acellular-pertussis (Tdap) vaccine is offered to all pregnant women in the Netherlands in their second trimester since December 2019. However, former studies solely investigated the socio-psychological factors that influence vaccine acceptance among pregnant women in the third trimester. We identified predicting factors for attitude, intention and acceptance of maternal Tdap vaccination during the second trimester of pregnancy.

Maternal vaccination against pertussis as part of the national immunization program: a qualitative evaluation among obstetric care providers one year after the implementation in December 2019.

Background: Immunization of pregnant women with a tetanus-diphtheria-and-acellular-pertussis (Tdap) vaccine is an effective and safe way to protect infants from pertussis before their primary vaccinations. Vaccine uptake among pregnant women is influenced by their care providers' attitudes toward maternal vaccination. This qualitative study aimed to evaluate the implementation of the maternal Tdap vaccination under the National Immunization Program of the Netherlands from the perspective of obstetric care providers.

Reactogenicity and safety of second trimester maternal tetanus, diphtheria and acellular pertussis vaccination in the Netherlands.

Background: Maternal tetanus-diphtheria-and-acellular-pertussis (Tdap) vaccination is offered to all pregnant women during their second trimester in the Netherlands since December 2019. We assessed second trimester Tdap vaccination reactogenicity and compared with third trimester data from a similar study. For safety assessment, adverse pregnancy outcomes were compared with national data from 2018, before Tdap vaccine-introduction.

More than 10 years after introduction of an acellular pertussis vaccine in infancy: a cross-sectional serosurvey of pertussis in the Netherlands.

Background: Pertussis is a respiratory disease and still endemic despite high vaccination coverage. In the Dutch national immunisation programme (NIP) whole cell pertussis (wP) priming vaccines for infants were replaced by acellular pertussis (aP) priming vaccines in 2005. Serosurveillance gives the opportunity to objectively monitor effects of changes in the NIP on infection prevalence and vaccine response in the population over time.

Study protocol of the PIMPI-project, a cohort study on acceptance, tolerability and immunogenicity of second trimester maternal pertussis immunization in relation to term and preterm infants.

Background: Maternal immunization confers passive immunity to the fetus by transplacental antibody transfer. Infants may be better protected against pertussis if the mother received a diphtheriae, tetanus and acellular pertussis (Tdap) vaccination in the second trimester of pregnancy compared to the third trimester. This study evaluates IgG antibody concentrations in term and preterm infants at birth and 2 months after birth after maternal Tdap-vaccination between 20 and 24 w of gestation vs third trimester Tdap-vaccination.

Circulation of Bordetella pertussis in the Caribbean Netherlands: a population-based seroepidemiological study.

Objectives: Pertussis is a respiratory infectious disease caused by Bordetella pertussis. In the Caribbean Netherlands (CN), comprising the islands Bonaire, St Eustatius, and Saba, registration of cases is mandatory for disease surveillance. However, insufficient laboratory facilities hamper case confirmation, and circulation persists.

Short term impact of the COVID-19 pandemic on incidence of vaccine preventable diseases and participation in routine infant vaccinations in the Netherlands in the period March-September 2020.

We aimed to assess the impact of the COVID-19 pandemic on the incidence of vaccine-preventable diseases (VPDs) and participation in the routine infant vaccination programme in the Netherlands. The incidence of various VPDs initially decreased by 75-97% after the implementation of the Dutch COVID-19 response measures. The participation in the first measles-mumps-rubella vaccination among children scheduled for vaccination in March-September 2020 initially dropped by 6-14% compared with the previous year.

Background incidence rates of adverse pregnancy outcomes in the Netherlands: Data of 2006-2018.

Objective: Maternal vaccination is an effective and safe intervention to protect newborns against infectious diseases shortly after birth. We assessed background rates of adverse pregnancy outcomes before the implementation of a maternal pertussis immunisation programme in the Netherlands, to put into perspective the safety concerns about such outcomes following immunisation.

Study Design: In this retrospective cross-sectional study, annual numbers of pregnancy outcomes derived from the Dutch Perinatal Registry were used to calculate incidence rates per 10,000 in the 2006-2018 period.

Social-psychological determinants of maternal pertussis vaccination acceptance during pregnancy among women in the Netherlands.

Background: Maternal Pertussis Vaccination (MPV) during pregnancy became part of the National Immunization Program in the Netherlands late 2019. This study aims to identify social-psychological factors associated with MPV acceptance among Dutch women to add to the current understanding of vaccine hesitancy worldwide, and to inform the development of communication and information campaigns about MPV.

Methods: We conducted a cross-sectional study using an online survey among 611 women (174 pregnant women, 205 women who had given birth in the past two years and 232 women of 20-35 years old).

Quantifying outcome misclassification in multi-database studies: The case study of pertussis in the ADVANCE project.

Background: The Accelerated Development of VAccine beNefit-risk Collaboration in Europe (ADVANCE) is a public-private collaboration aiming to develop and test a system for rapid benefit-risk (B/R) monitoring of vaccines using European healthcare databases. Event misclassification can result in biased estimates. Using different algorithms for identifying cases of Bordetella pertussis (BorPer) infection as a test case, we aimed to describe a strategy to quantify event misclassification, when manual chart review is not feasible.

Advance system testing: Vaccine benefit studies using multi-country electronic health data - The example of pertussis vaccination.

The Accelerated Development of VAccine benefit-risk Collaboration in Europe (ADVANCE), a public-private consortium, implemented and tested a distributed network system for the generation of evidence on the benefits-risks of marketed vaccines in Europe. We tested the system by estimating the incidence rate (IR) of pertussis and pertussis-related complications in children vaccinated with acellular (aP) and whole-cell (wP) pertussis vaccine. Data from seven electronic databases from four countries (Denmark: AUH and SSI, Spain: SIDIAP and BIFAP, UK: THIN and RCGP RSC and Italy: Pedianet) were included in a retrospective cohort analysis.

Pertussis hospitalizations among term and preterm infants: clinical course and vaccine effectiveness.

Background: Pertussis causes severe disease in young unvaccinated infants, with preterms potentially at highest risk. We studied pertussis in hospitalized infants as related to gestational age (GA) and vaccination history.

Methods: Medical record data of 0-2y old patients hospitalized for pertussis during 2005-2014 were linked to vaccination data.

Effect of measles vaccination in infants younger than 9 months on the immune response to subsequent measles vaccine doses: a systematic review and meta-analysis.

Background: Vaccinating infants with a first dose of measles-containing vaccine (MCV1) before 9 months of age in high-risk settings has the potential to reduce measles-related morbidity and mortality. However, there is concern that early vaccination might blunt the immune response to subsequent measles vaccine doses. We systematically reviewed the available evidence on the effect of MCV1 administration to infants younger than 9 months on their immune responses to subsequent MCV doses.

Immunogenicity, effectiveness, and safety of measles vaccination in infants younger than 9 months: a systematic review and meta-analysis.

Background: Measles is an important cause of death in children, despite the availability of safe and cost-saving measles-containing vaccines (MCVs). The first MCV dose (MCV1) is recommended at 9 months of age in countries with ongoing measles transmission, and at 12 months in countries with low risk of measles. To assess whether bringing forward the age of MCV1 is beneficial, we did a systematic review and meta-analysis of the benefits and risks of MCV1 in infants younger than 9 months.

Narcolepsy and adjuvanted pandemic influenza A (H1N1) 2009 vaccines - Multi-country assessment.

Background: In 2010, a safety signal was detected for narcolepsy following vaccination with Pandemrix, an AS03-adjuvanted monovalent pandemic H1N1 influenza (pH1N1) vaccine. To further assess a possible association and inform policy on future use of adjuvants, we conducted a multi-country study of narcolepsy and adjuvanted pH1N1 vaccines.

Methods: We used electronic health databases to conduct a dynamic retrospective cohort study to assess narcolepsy incidence rates (IR) before and during pH1N1 virus circulation, and after pH1N1 vaccination campaigns in Canada, Denmark, Spain, Sweden, Taiwan, the Netherlands, and the United Kingdom.

Enhanced acquisition rate in adolescents during the 2012 epidemic in the Netherlands and evidence for prolonged antibody persistence after infection.

IntroductionIn 2012 a large epidemic of pertussis occurred in the Netherlands. We assessed pertussis toxin (PT) antibody levels in longitudinal serum samples from Dutch 10-18 year-olds, encompassing the epidemic, to investigate pertussis infection incidence. : Blood was sampled in October 2011 (n = 239 adolescents), then 1 year (2012; n = 228) and 3 years (2014; n = 167) later.

Elevated Immune Response Among Children 4 Years of Age With Pronounced Local Adverse Events After the Fifth Diphtheria, Tetanus, Acellular Pertussis Vaccination.

Background: In the Netherlands, acellular pertussis vaccines replaced the more reactogenic whole-cell pertussis vaccines. This replacement in the primary immunization schedule of infants coincided with a significant increase in pronounced local adverse events (AEs) in 4 years old children shortly after the administration of a fifth diphtheria, tetanus, acellular pertussis and inactivated polio (DTaP-IPV) vaccine. The objective of this study was to investigate possible differences in vaccine antigen-specific immune responses between children with and without a pronounced local AE after the fifth DTaP-IPV vaccination.

Dutch national immunization schedule: compliance and associated characteristics for the primary series.

Unlabelled: In the Netherlands, the recommended priming immunization schedule for diphtheria, tetanus, pertussis and polio (DTaP-IPV) is at 2, 3 and 4 months of age. We evaluated the compliance with the recommended schedule, as well as its characteristics. We included all infants born between 2007 and 2012 who received minimally one DTaP-IPV vaccination (n = 1,061,578).

Comparison of the tolerability of newly introduced childhood vaccines in the Netherlands.

Unlabelled: In 2011, the 7-valent conjugated pneumococcal vaccine (PCV7) was replaced by the 10-valent vaccine (PCV10) and universal hepatitis B vaccination has been introduced in the Netherlands. A questionnaire study was conducted to assess the tolerability of DTaP-IPV-Hib + PCV7 (PCV7-cohort), DTaP-IPV-Hib + PCV10 (PCV10-cohort), and DTaP-IPV-Hib-HepB + PCV10 (HepB-cohort). Parents were asked to report in questionnaires local reactions and systemic adverse events (AEs) before and after vaccination of their infant at 2, 3, 4, and 11 months of age.

Effectiveness of Early Measles, Mumps, and Rubella Vaccination Among 6-14-Month-Old Infants During an Epidemic in the Netherlands: An Observational Cohort Study.

Background: Routinely, the first measles, mumps, and rubella (MMR) vaccine dose is given at 14 months of age in the Netherlands. However, during a measles epidemic in 2013-2014, MMR vaccination was also offered to 6-14-month-olds in municipalities with <90% MMR vaccination coverage. We studied the effectiveness of the early MMR vaccination schedule.

Comparison of different collection methods for reported adverse events following pandemic and seasonal influenza vaccination.

Background: During the 2009/2010 season, information on adverse events after administration of seasonal and pandemic influenza vaccines was collected by different active surveys in the Netherlands. In the present paper, we compared data from a paper-based questionnaire with data from a web-based questionnaire with respect to outcomes and target population, in order to guide future influenza vaccine safety monitoring.

Methods: The paper-based survey collected data from patients who attended primary care practices in the province of Utrecht for influenza vaccination.