Effect of vaccination programmes on mortality burden among children and young adults in the Netherlands during the 20th century: a historical analysis

Childhood vaccination coverage and regional differences in Swiss birth cohorts 2012-2021: Are we on track?

AIMS

Many western countries are challenged by delayed and insufficient vaccination coverage rates in children, and thus missing WHO coverage targets. This study aimed to estimate vaccination coverage and timeliness in Swiss children over a decade. Furthermore, we evaluated the impact of COVID-19, regional variations, and the adherence to the amended vaccination schedule in 2019.

METHODS

Retrospective observational study with Swiss health insurance claims data including birth cohorts 2012-2021 of children continuously observed until ages 13, 25, and 48 months respectively. We used population-weighted proportions and time-to-event analyses to describe coverage and timeliness of diphtheria/tetanus/pertussis/poliomyelitis/haemophilus influenzae type b (DTaP-IPV-Hib), measles/mumps/rubella (MMR), hepatitis B (HBV), pneumococcal (PCV), and meningococcal (MCV) vaccinations according to the national schedule. The potential impact of COVID-19 and vaccination schedule adherence were evaluated descriptively. Logistic regression was used to investigate regional factors potentially associated with non-vaccination.

RESULTS

120,073 children, representing between 12 and 17 % of all Swiss children born in corresponding years, were included. Coverage remained stable or improved over the years. The 2019 amendment of the national immunization schedule was associated with an increase of ~10 % points in full coverage in Swiss children for DTaP-IPV-Hib, MMR and HBV despite the concurrent COVID-19 pandemic. Nonetheless, full vaccination coverage remained below 90 % with many vaccination series being delayed or not completed. The comparison across the different vaccines revealed large differences in coverage. Moreover, we observed large regional differences in non-vaccination with children living in rural and German-speaking areas more likely to be entirely unvaccinated.

CONCLUSION

Full vaccination coverage in Swiss children is still below 90 % with many vaccinations administered delayed. Given regional differences, missed or delayed booster vaccinations, and differences in vaccine-specific acceptability, more effort may be needed to achieve national vaccination targets.

Regional differences in historical diphtheria and scarlet fever notification rates in The Netherlands, 1905-1925: a spatial-temporal analysis

BACKGROUND

We describe how rates of two frequently occurring notifiable diseases-diphtheria and scarlet fever-varied between regions of The Netherlands in the early twentieth century, and identify potential factors underlying this variation.

METHODS

Digitized weekly mandatory notification data for 1905-1925, municipality level, were aggregated into 27 'spatial units' defined by unique combinations of province and population density category (high: more than 4500; mid : 1250-4500; low: less than 1250 inhabitants km-2). Generalized additive regression models were fitted to estimate the associations between notification rates and population density, infant mortality rate and household income, while adjusting for temporal trends per spatial unit.

RESULTS

Annual per capita notification rates for both diphtheria and scarlet fever tended to rise from the beginning of the period 1905-1925 until peaking around 1918/1919. Adjusted diphtheria notification rates were higher for high- and mid- compared with low-density municipalities (by 71.6 cases per 100 000, 95% confidence interval (CI) : 52.7-90.5; 39.0/100 k, 95% CI : 24.7-53.3, respectively). Scarlet fever showed similar associations with population density (35.7 cases per 100 000, 95% CI : 9.4-62.0; 21.4/100 k, 95% CI: 1.5-41.3).

CONCLUSIONS

There was considerable spatial variation in notification rates for both diseases in early twentieth century Netherlands, which could partly be explained by factors capturing variation in living conditions and socio-economic circumstances. These findings aid understanding of contemporary respiratory infection transmission.

Infant and child mortality in the Netherlands 1935-47 and changes related to the Dutch famine of 1944-45: A population-based analysis

Precise estimates of the impact of famine on infant and child mortality are rare due to lack of representative data. Using vital statistics reports on the Netherlands for 1935-47, we examine the impact of the Dutch famine (November 1944 to May 1945) on age-specific mortality risk and cause of death in four age groups (stillbirths, <1 year, 1-4, 5-14) in the three largest famine-affected cities and the remainder of the country. Mortality during the famine is compared with the pre-war period January 1935 to April 1940, the war period May 1940 to October 1944, and the post-war period June 1945 to December 1947. The famine's impact was most visible in infants because of the combined effects of a high absolute death rate and a threefold increase in proportional mortality, mostly from gastrointestinal conditions. These factors make infant mortality the most sensitive indicator of famine severity in this setting and a candidate marker for comparative use in future studies.

Infants' immunisations, their timing and the risk of allergic diseases (INITIAL): an observational prospective cohort study protocol

INTRODUCTION

Vaccinations are considered to have a large impact on disease control, hence a multitude of vaccines in infancy is recommended. Retrospective studies suggest a possible relation between timing, kind or number of vaccines given in the first year of life and the subsequent incidence of allergic diseases. It must be clarified whether a causal relationship exists to ensure safety and reduce vaccine hesitancy.

METHODS AND ANALYSIS

Due to the high recommendation rate of vaccines, a long-term randomised controlled trial is not considered as ethically acceptable. Therefore, this study aims to observe prospectively the allergic incidence at the age of 5 years after various vaccine interventions in the early months of life.Parents of infants up to the age of 4-6 weeks will be recruited before the first recommended vaccination. Relevant prognostic factors for allergies, status of immunisation and general health will be evaluated up to the age of 5.Allergic symptoms will be assessed by the International Study of Asthma and Allergies in Childhood-questionnaire and a medical confirmation of the allergy is mandatory.The main objective is to compare the incidence of asthma, atopic dermatitis, rhinoconjunctivitis, food allergy or any of these atopies at the age of 5 between infants who were not vaccinated or were vaccinated according to recommendations in the first year of life.The sample size calculation with about 4000 participants can prove a 5% difference to the basic prevalence with about 80% power and global 5% alpha error for the five primary endpoints adjusting according to Bonferroni-Holm and assuming a rate of 10% not early vaccinated infants.

ETHICS AND DISSEMINATION

The study was registered (DRKS00029677) and has received approval by the ethics committee of Universität Witten/Herdecke (no. 113/2022). The results will be published.

Grandmother presence improved grandchild survival against childhood infections but not vaccination coverage in historical Finns

Grandmother presence can improve the number and survival of their grandchildren, but what grandmothers protect against and how they achieve it remains poorly known. Before modern medical care, infections were leading causes of childhood mortality, alleviated from the nineteenth century onwards by vaccinations, among other things. Here, we combine two individual-based datasets on the genealogy, cause-specific mortality and vaccination status of eighteenth- and nineteenth-century Finns to investigate two questions. First, we tested whether there were cause-specific benefits of grandmother presence on grandchild survival from highly lethal infections (smallpox, measles, pulmonary and diarrhoeal infections) and/or accidents. We show that grandmothers decreased all-cause mortality, an effect which was mediated through smallpox, pulmonary and diarrhoeal infections, but not via measles or accidents. Second, since grandmothers have been suggested to increase vaccination coverage, we tested whether the grandmother effect on smallpox survival was mediated through increased or earlier vaccination, but we found no evidence for such effects. Our findings that the beneficial effects of grandmothers are in part driven by increased survival from some (but not all) childhood infections, and are not mediated via vaccination, have implications for public health, societal development and human life-history evolution.

Health and Economic Evaluation of Vaccination Against Pertussis in China: A 40-Year Analysis

OBJECTIVES

This study aimed to evaluate the health and economic impact of diphtheria, tetanus, whole-cell pertussis vaccine (DTwP) and diphtheria-tetanus-acellular pertussis vaccine (DTaP) vaccination on pertussis prevention and control in China during the 40 years from 1978 to 2017.

METHODS

We conducted cost-benefit analyses with a decision tree model populated with historical vaccination coverage levels and pertussis incidence and mortality data from before 1978 and during 1978 to 2017. We modeled 40 birth cohorts from birth until death. Costs and benefits were estimated from direct cost and societal perspectives (direct and indirect costs). Costs and benefits were adjusted to 2017 US dollars (USD), and future values were discounted at a 3% annual rate. We calculated net benefit values (net savings) and benefit-cost ratios of pertussis vaccination of children younger than 5 years. We conducted sensitivity analyses by varying key parameters within plausible ranges.

RESULTS

Without DTwP and DTaP vaccination, there would be an estimated 115.76 million pertussis cases and 426 650 pertussis deaths in the 40 cohorts. With DTwP/DTaP vaccination, pertussis cases and deaths were decreased by an estimated 92.57% and 97.43%, saving 46 987.81 million USD in direct costs and 82 013.37 million USD from societal perspective. Pertussis vaccination program costs were 2168.76 million USD and 3961.28 million USD from direct cost and societal perspectives. Benefit-cost ratios were 21.67:1 from the direct cost perspective and 20.70:1 from the societal perspective. Sensitivity analyses showed the results to be robust.

CONCLUSIONS

Over the lifetime of 40 birth cohorts, China's immunization program is preventing 93% of pertussis cases and 97% of pertussis deaths, resulting in substantial savings to the healthcare system and society.

Essential childhood immunization in 43 low- and middle-income countries: Analysis of spatial trends and socioeconomic inequalities in vaccine coverage

BACKGROUND

Globally, access to life-saving vaccines has improved considerably in the past 5 decades. However, progress has started to slow down and even reverse in recent years. Understanding subnational heterogeneities in essential child immunization will be critical for closing the global vaccination gap.

METHODS AND FINDINGS

We use vaccination information for over 220,000 children across 1,366 administrative regions in 43 low- and middle-income countries (LMICs) from the most recent Demographic and Health Surveys. We estimate essential immunization coverage at the national and subnational levels and quantify socioeconomic inequalities in such coverage using adjusted concentration indices. Within- and between-country variations are summarized via the Theil index. We use local indicator of spatial association (LISA) statistics to identify clusters of administrative regions with high or low values. Finally, we estimate the number of missed vaccinations among children aged 15 to 35 months across all 43 countries and the types of vaccines most often missed. We show that national-level vaccination rates can conceal wide subnational heterogeneities. Large gaps in child immunization are found across West and Central Africa and in South Asia, particularly in regions of Angola, Chad, Nigeria, Guinea, and Afghanistan, where less than 10% of children are fully immunized. Furthermore, children living in these countries consistently lack all 4 basic vaccines included in the WHO's recommended schedule for young children. Across most countries, children from poorer households are less likely to be fully immunized. The main limitations include subnational estimates based on large administrative divisions for some countries and different periods of survey data collection.

CONCLUSIONS

The identified heterogeneities in essential childhood immunization, especially given that some regions consistently are underserved for all basic vaccines, can be used to inform the design and implementation of localized intervention programs aimed at eliminating child suffering and deaths from existing and novel vaccine-preventable diseases.

Historical trends in mortality from "older" vaccine-preventable diseases, Colombia: implications for elimination and control

OBJECTIVE

This study aimed to describe the trends in mortality from eight vaccine-preventable diseases in Colombia in the last 40 years and their relationship with vaccination coverage.

STUDY DESIGN

It is a population-based descriptive study.

METHODS

The frequencies of deaths by decade, disease, sex, and the specific mortality rates by age group were calculated. Using a negative binomial regression model, the 10-year changes in mortality and their relationship with vaccination coverage were determined.

RESULTS

The number of deaths and the adjusted rates decreased since 1989 in all diseases (incidence rate ratio <1 when compared with the 1979-1988 decade). Vaccination coverage below 90% is associated with an increase in mortality from diphtheria, measles, mumps, neonatal tetanus, and pertussis.

CONCLUSION

Historical changes in mortality support the benefits of vaccination, but new efforts are required to sustain the elimination of diseases.

The Long-Term Success of Mandatory Vaccination Laws After Implementing the First Vaccination Campaign in 19th Century Rural Finland

In high-income countries, childhood infections are on the rise, a phenomenon attributed in part to persistent hesitancy toward vaccines. To combat vaccine hesitancy, several countries recently made vaccinating children mandatory, but the effect of such vaccination laws on vaccination coverage remains debated, and the long-term consequences are unknown. Here we quantified the consequences of vaccination laws on vaccination coverage, monitoring for a period of 63 years (1837-1899) rural Finland's first vaccination campaign against the highly lethal childhood infection smallpox. We found that annual vaccination campaigns were focused on children up to 1 year old and that their vaccination coverage was low and declined over time until the implementation of the vaccination law, which stopped the declining trend and was associated with an abrupt coverage increase, of 20%, to cover >80% of all children. Our results indicate that vaccination laws can have a long-term beneficial effect of increasing the vaccination coverage and will help public health practitioners to make informed decisions on how to act against vaccine hesitancy and optimize the impact of vaccination programs.

Prophylactic and Therapeutic EBV Vaccines: Major Scientific Obstacles, Historical Progress, and Future Direction

The Epstein-Barr virus (EBV) infects more than 95% of adults worldwide and is associated with various malignant tumors and immune diseases, imparting a huge disease burden on the human population. Available EBV vaccines are imminent. Prophylactic vaccines can effectively prevent the spread of infection, whereas therapeutic vaccines mainly stimulate cell-mediated immunity and kill infected cells, thus curbing the development of malignant tumors. Nevertheless, there are still no approved EBV vaccines after decades of effort. The complexity of the EBV life cycle, the lack of appropriate animal models, and the limited reports on adjuvant selection and immune responses are gravely impeding progress in EBV vaccines. The soluble gp350 vaccine could reduce the incidence of infectious mononucleosis (IM), which seemed to offer hope, but could not prevent EBV infection. Continuous research and vaccine trials provide deep insights into the structural biology of viruses, the designs for immunogenicity, and the evolving vaccine platforms. Moreover, the new vaccine candidates are expected to achieve further success via combined immunization to elicit both a dual protection of B cells and epithelial cells, and sustainable immunization against infected cells at several phases of infection.

[Factors associated with scale-up human papillomavirus (HPV) vaccine in Senegal: a case-control survey of parents]

Introduction

après une phase pilote, le Sénégal est le premier pays en Afrique de l´Ouest à introduire le vaccin contre le cancer du col de l´utérus dans le Programme élargi de vaccination. Malgré la gratuité et la disponibilité du vaccin, la couverture est restée faible. L´objectif de cette étude était d´identifier les facteurs associés à la vaccination des filles contre le virus du papillome humain.

Méthodes

il s´agissait d´une étude analytique de type cas-témoin réalisée du 4 au 20 janvier 2020 à Dakar. La population d´étude était constituée de parents ou tuteurs de filles âgées de 9 à 10 ans. Nous avons réalisé un échantillonnage en grappes, des entretiens structurés directs et une revue documentaire. Les caractéristiques sociodémographiques, les connaissances des parents/tuteurs et les informations sur l´acte vaccinal ont été collectées à l´aide d´un questionnaire standardisé. Une régression logistique a permis d´estimer les odds-ratio.

Résultats

au cours de cette étude, 510 cas et 510 témoins, soient 1020 parents/tuteurs étaient interviewés. Les facteurs significatifs associés à la vaccination des filles étaient: l´instruction des parents/tuteurs (ORa=1,97; [1,81-2,25]), la connaissance de la maladie (ORa=3,05; [2,75-4,53], le revenu élevé du ménage (ORa=1,21; [1,13-1,85]), la crainte des effets secondaires (ORa=0,35; [0,27-0,44]), la réception de messages via internet/réseaux sociaux (ORa=0,54; [0,41-0,92]) et les horaires de vaccination adaptées à la communauté (ORa= 2,12 [1,59-2,64]).

Conclusion

la vaccination des filles peut être améliorée par un renforcement des connaissances des parents à travers des canaux appropriés et une meilleure organisation des services de santé.

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 20⁰ and 24⁰ w of gestation vs third trimester Tdap-vaccination. Further aims are assessing the determinants that underlie acceptance of second trimester maternal Tdap-vaccination as well as the tolerability of vaccination.

Methods

This prospective cohort study consists of two parts. In the acceptance part, pregnant women complete a questionnaire on determinants that underlie acceptance of a second trimester Tdap-vaccination, which is offered subsequently between 20⁰ and 24⁰ w of gestation. Vaccinated women complete an additional questionnaire on vaccination tolerability. Vaccinated women may also participate in the immunogenicity part, in which blood is drawn from mother at delivery and from infant at birth and 2 months after birth. Women are also eligible for the immunogenicity part if they received a Tdap-vaccination between 20⁰ and 24⁰ w of gestation via the national immunization program and get hospitalized for an imminent preterm delivery. Blood sampling continues until 60 term and 60 preterm mother-infant-pairs have been included. Pertussis-specific IgG antibody concentrations are determined in serum using a fluorescent bead-based multiplex immunoassay. For term infants, non-inferiority in IgG antibody concentrations against pertussis toxin (anti-PT) will be assessed referred to a historical control group in which mothers were Tdap-vaccinated between 30⁰ and 32⁰ w of gestation. For preterm infants, non-inferiority of anti-PT IgG concentrations is referred to as 85% of infants having ≥ 20 international units/mL at 2 months after birth.

Discussion

This study investigates acceptance, tolerability and immunogenicity regarding maternal Tdap-immunization between 20⁰ and 24⁰ w of gestation. Its results provide insight into the effects of second trimester Tdap-vaccination on IgG antibody concentrations in term and preterm infants before primary infant vaccinations. Results on acceptance and tolerability guide antenatal care providers in communication with pregnant women and maintain the safety of second trimester Tdap-vaccination.

Trial registration: EU Clinical Trials Register, 2018-002976-41, retrospectively registered 24 July 2019, https://www.clinicaltrialsregister.eu/ctr-search/search?query=2018-002976-41.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06559-w.

Rotavirus Vaccination of Infants Delayed and Limited within the National Immunization Programme in the Netherlands: An Opportunity Lost

In this study, we estimated the benefits of rotavirus vaccination for infants had the rotavirus vaccine been introduced in the Netherlands as of its market authorization in 2006. An age-structured, deterministic cohort model was developed to simulate different birth cohorts over a period of 15 years from 2006 until 2021, comparing both universal and targeted high-risk group vaccination to no vaccination. Different scenarios for the duration of protection (5 or 7 years) and herd immunity (only for universal vaccination) were analyzed. All birth cohorts together included 2.6 million infants, of which 7.9% were high-risk individuals, and an additional 13.2 million children between 1-15 years born prior to the first cohort in 2006. The costs and health outcomes associated with rotavirus vaccination were calculated per model scenario and discounted at 4% and 1.5%, respectively. Our analysis reveals that, had rotavirus vaccination been implemented in 2006, it would have prevented 356,800 (51% decrease) and 32,200 (5% decrease) cases of rotavirus gastroenteritis after universal and targeted vaccination, respectively. Over the last 15 years, this would have led to significant avoided costs and quality-adjusted life year losses for either vaccination strategy with the most favorable outcomes for universal vaccination. Clearly, an opportunity has been lost.

Estimating the health impact of vaccination against ten pathogens in 98 low-income and middle-income countries from 2000 to 2030: a modelling study

BACKGROUND

The past two decades have seen expansion of childhood vaccination programmes in low-income and middle-income countries (LMICs). We quantify the health impact of these programmes by estimating the deaths and disability-adjusted life-years (DALYs) averted by vaccination against ten pathogens in 98 LMICs between 2000 and 2030.

METHODS

16 independent research groups provided model-based disease burden estimates under a range of vaccination coverage scenarios for ten pathogens: hepatitis B virus, Haemophilus influenzae type B, human papillomavirus, Japanese encephalitis, measles, Neisseria meningitidis serogroup A, Streptococcus pneumoniae, rotavirus, rubella, and yellow fever. Using standardised demographic data and vaccine coverage, the impact of vaccination programmes was determined by comparing model estimates from a no-vaccination counterfactual scenario with those from a reported and projected vaccination scenario. We present deaths and DALYs averted between 2000 and 2030 by calendar year and by annual birth cohort.

FINDINGS

We estimate that vaccination of the ten selected pathogens will have averted 69 million (95% credible interval 52-88) deaths between 2000 and 2030, of which 37 million (30-48) were averted between 2000 and 2019. From 2000 to 2019, this represents a 45% (36-58) reduction in deaths compared with the counterfactual scenario of no vaccination. Most of this impact is concentrated in a reduction in mortality among children younger than 5 years (57% reduction [52-66]), most notably from measles. Over the lifetime of birth cohorts born between 2000 and 2030, we predict that 120 million (93-150) deaths will be averted by vaccination, of which 58 million (39-76) are due to measles vaccination and 38 million (25-52) are due to hepatitis B vaccination. We estimate that increases in vaccine coverage and introductions of additional vaccines will result in a 72% (59-81) reduction in lifetime mortality in the 2019 birth cohort.

INTERPRETATION

Increases in vaccine coverage and the introduction of new vaccines into LMICs have had a major impact in reducing mortality. These public health gains are predicted to increase in coming decades if progress in increasing coverage is sustained.

FUNDING

Gavi, the Vaccine Alliance and the Bill & Melinda Gates Foundation.

Vaccination of immune compromised children-an overview for physicians

Immune compromised children are threatened by a higher risk of infections; some of these are preventable by vaccination. Primary care physicians play a fundamental role in optimising vaccination status. In this narrative review, we present the evidence on vaccine safety and immunogenicity in immune compromised children and discuss in which conditions live-attenuated vaccines can possibly be used. Vaccination schedules differ in some of these conditions, including the use of vaccines with higher antigenic contents (e.g. high-dose hepatitis B vaccine), additional vaccine doses (e.g. 2-dose schedule meningococcal vaccine), more frequent booster doses (e.g. life-long pneumococcal vaccine booster), supplementary vaccines (e.g. meningococcal B vaccine) and use of vaccines beyond the age of usual recommendation (e.g. Haemophilus influenza type b vaccine after 5 years of age). Serological monitoring is a useful tool for customizing vaccination schedule in immune compromised children, confirming adequate vaccine response and documenting seroprotection (especially against measles and varicella). Finally, verification of vaccination status of all household members can prevent them being vector of transmission of an infection to the immune compromised children. Conclusion: Intensified information strategies are needed to improve trust, rectify perceived risks and improve vaccine acceptability; primary physicians can play a critical role in the latter. What is Known: • Physician's awareness is key to success, since it repeatedly correlates with higher vaccination rates What is New: • The vaccination status of immunocompromised children is rarely up-to-date • Knowing the latest vaccine recommendations is challenging, as they differ for each medical condition and change periodically • This review summarises the vaccine recommendations for children with compromised immune systems and highlights how paediatricians play a key role in coordinating their application.

Vaccination Policies: Between Best and Basic Interests of the Child, between Precaution and Proportionality

How should liberal-democratic governments deal with emerging vaccination hesitancy when that leads to the resurgence of diseases that for decades were under control? This article argues that vaccination policies should be justified in terms of a proper weighing of the rights of children to be protected against vaccine-preventable diseases and the rights of parents to raise their children in ways that they see fit. The argument starts from the concept of the ‘best interests of the child involved’. The concept is elaborated for this context into the dual regime structure in which parents have fiduciary authority over what they consider to be best for their child, and the state has fiduciary authority over a child’s basic interests. This argument leads to conditional mandatory vaccination programs that should be informed by a correct balancing of the two legal principles of proportionality and precaution. This results in contextual childhood vaccination policies of upscaling interference: a three-tiered approach of increased intrusion, from voluntary program when possible and mandatory or even compulsory programs when necessary to protect the child’s basic interests.

Association between season of vaccination and antibody levels against infectious diseases

Vaccination has reduced the disease burden of vaccine-preventable diseases. However, the extent to which seasonal cycles of immunity could influence vaccine-induced immunity is not well understood. A national cross-sectional serosurveillance study performed in the Netherlands (Pienter-2) yielded data to investigate whether season of vaccination was associated with antibody responses induced by DT-IPV (diphtheria, tetanus and poliomyelitis), MMR (measles, mumps and rubella) and meningococcus C (MenC) vaccines in children. In total, 434 children met the inclusion criteria to study DT-IPV immunity, 811 for MMR and 311 for MenC. Differences in log(antibody levels) by season of vaccination were investigated with linear multivariable regression analyses. Seroconversion rates varied according to season of vaccination for rubella (90% of autumn-vaccinated children vs. 99% of winter-vaccinated had concentrations above cut-off levels). Summer-vaccinated boys showed a slower decline of tetanus antibodies (6% per month), in comparison with winter-vaccinated boys. In conclusion, season of vaccination showed little association with immunological protection. However, a number of associations were seen with a P-value of about 0.03; and adding data from a just-completed nationwide serological study might add more power to the current study. Further immunological and longitudinal investigations could help understand the mechanisms of seasonal influence in vaccine-induced responses.

Major Scientific Hurdles in HIV Vaccine Development: Historical Perspective and Future Directions

Following the discovery of HIV as a causative agent of AIDS, the expectation was to rapidly develop a vaccine; but thirty years later, we still do not have a licensed vaccine. Progress has been hindered by the extensive genetic variability of HIV and our limited understanding of immune responses required to protect against HIV acquisition. Nonetheless, valuable knowledge accrued from numerous basic and translational science research studies and vaccine trials has provided insight into the structural biology of the virus, immunogen design and novel vaccine delivery systems that will likely constitute an effective vaccine. Furthermore, stakeholders now appreciate the daunting scientific challenges of developing an effective HIV vaccine, hence the increased advocacy for collaborative efforts among academic research scientists, governments, pharmaceutical industry, philanthropy, and regulatory entities. In this review, we highlight the history of HIV vaccine development efforts, highlighting major challenges and future directions.

Skin thickness in neonates: Implications for intradermal vaccination

INTRODUCTION

Intradermal (ID) injection is an alternate route that enhances vaccine immunogenicity and decreases vaccine dose. Regular immunization usually starts at age 2 months, and the limited immune capacity of neonates and young infants makes them vulnerable to infection. Successful ID vaccine delivery in this population requires knowledge of skin thickness. Although skin thickness has been evaluated in infants aged 2 months or older, no comparable data are available for neonates, including preterm neonates.

METHODS

This prospective observational study used ultrasonography to assess skin thickness in 70 neonates (35 full-term and 35 preterm neonates) at deltoid, suprascapular, and thigh sites. The measurements were compared in relation to anatomical site, between full-term and preterm infants, and with skin thickness values for children aged 2 months or older, which were collected in our previous study using the same measurement technique.

RESULTS

In full-term neonates, skin was significantly thicker at the suprascapular site than at the deltoid and thigh sites (P < 0.05); in preterm neonates, skin was significantly thicker at the suprascapular site than at the thigh site (P < 0.05). Skin thickness values at all three sites were significantly lower in preterm neonates than in full-term neonates (P < 0.05). As compared with skin thickness values for infants aged 2 months, values for full-term neonates were significantly lower for the deltoid and suprascapular sites (P < 0.001).

CONCLUSIONS

Skin thickness values for neonates were affected by prematurity and were significantly lower than those for infants aged 2 months. These findings are important in the design of ID injection devices for neonates and young infants.

Disease burden of varicella versus other vaccine-preventable diseases before introduction of vaccination into the national immunisation programme in the Netherlands

Introduction

Estimating burden of disease (BoD) is an essential first step in the decision-making process on introducing new vaccines into national immunisation programmes (NIPs). For varicella, a common vaccine-preventable disease, BoD in the Netherlands was unknown.

Aim

To assess national varicella BoD and compare it to BoD of other vaccine-preventable diseases before their introduction in the NIP.

Methods

In this health estimates reporting study, BoD was expressed in disability-adjusted life years (DALYs) using methodology from the Burden of Communicable Diseases in Europe (BCoDE)-project. As no parameters/disease model for varicella (including herpes zoster) were available in the BCoDE toolkit, incidence, disease progression model and parameters were derived from seroprevalence, healthcare registries and published data. For most other diseases, BoD was estimated with existing BCoDE-parameters, adapted to the Netherlands if needed.

Results

In 2017, the estimated BoD of varicella in the Netherlands was 1,800 (95% uncertainty interval (UI): 1,800–1,900) DALYs. Herpes zoster mainly contributed to this BoD (1,600 DALYs; 91%), which was generally lower than the BoD of most current NIP diseases in the year before their introduction into the NIP. However, BoD for varicella was higher than for rotavirus gastroenteritis (1,100; 95%UI: 440–2,200 DALYs) and meningococcal B disease (620; 95%UI: 490–770 DALYs), two other potential NIP candidates.

Conclusions

When considering the introduction of a new vaccine in the NIP, BoD is usually estimated in isolation. The current approach assesses BoD in relation to other vaccine-preventable diseases’ BoD, which may help national advisory committees on immunisation and policymakers to set vaccination priorities.

Understanding factors associated with vaccine uptake and vaccine hesitancy in patients with rheumatoid arthritis: a scoping literature review

Due to higher risk of complications associated with vaccine-preventable infections (e.g., influenza, pneumococcus), patients with rheumatoid arthritis (RA) are a priority group for vaccination. However, vaccination rates among RA patients are low, indicating a need to understand the determinants of vaccine hesitancy in this group. This study conducted an evidence synthesis of various stakeholders' (patients, physicians/rheumatologists) perspectives about the determinants of vaccine hesitancy and uptake among patients with RA. We searched three bibliographic and reference databases (PUBMED, PsychINFO, and SCOPUS) for relevant English or French articles published in peer-reviewed journals through July 2019 that conducted either qualitative or quantitative assessments of vaccine hesitancy or uptake. Key themes associated with vaccination hesitancy themes according to different stakeholders were extracted and summarized. Of 783 unique citations, 16 articles met the inclusion criteria. Most studies (78%; n = 134,787 RA patients) examined barriers reported by patients, 13% (n = 114) by rheumatologists. Two principal themes and six sub-themes associated with vaccination hesitancy were identified among both patients and rheumatologists: 'social and contextual factors' (including healthcare policies, access to care/high patient loads, and social/media influences) and 'patient and provider factors' (including patient understanding of benefits and risks, provider awareness of guidelines and perceived responsibility for vaccination, and implementation challenges). Determinants of vaccine hesitancy and uptake in RA identified by different stakeholders implicate patient-, provider-, and healthcare system‑related factors. This information is relevant for the design of interventions that target improving vaccine uptake in RA patients.

Vaccinating for Whom? Distinguishing between Self-Protective, Paternalistic, Altruistic and Indirect Vaccination

Preventive vaccination can protect not just vaccinated individuals, but also others, which is often a central point in discussions about vaccination. To date, there has been no systematic study of self- and other-directed motives behind vaccination. This article has two major goals: first, to examine and distinguish between self- and other-directed motives behind vaccination, especially with regard to vaccinating for the sake of third parties, and second, to explore some ways in which this approach can help to clarify and guide vaccination debates and policy. I propose conceiving of vaccination in terms of three basic elements: the vaccination decision-maker, the vaccine recipient and the primary beneficiary. I develop a taxonomy based on the relations between these elements to distinguish four kinds of vaccination: self-protective, paternalistic, altruistic and indirect. I finally discuss the case of human papillomavirus vaccine regulation for men and women to show how each kind of vaccination is associated with and raises specific ethical questions.

Trends in governmental expenditure on vaccination programmes in the Netherlands, a historical analysis

BACKGROUND

Health economic evaluations are often required before implementing a vaccination programme. Such evaluations rarely consider the historical context of a vaccination programme. We review the financial history of vaccination programmes in the Netherlands, and compare these to demographic and macroeconomic developments as well as avoided mortality burden.

METHODS

Previously uncatalogued historical expenditures on the Dutch National Immunisation Programme (NIP) and influenza vaccination were obtained from official reports. Costs were adjusted for inflation using Consumer Price Indices and expressed in Euro of 2016. Estimates on mortality burden averted were obtained from previous research and used to calculate the ratio of expenses to averted mortality burden for vaccinations against diphtheria, tetanus, pertussis, polio, measles, mumps and rubella for birth cohorts 1953-1992.

RESULTS

Developments towards a uniform government funded NIP started early 1950s with vaccinations against diphtheria, pertussis and tetanus, culminating in its official launch in 1957 together with polio vaccinations. Since the 1980s, expenditure increased nearly five-fold mostly due to the addition of new vaccines, while spending on already implemented vaccinations tended to decline. Overall, expenditure increased from € 5 million in 1957 to € 93 million in 2014. Relative to total healthcare expenditure, the NIP contributed little, ranging between 0.05% and 0.14%. Spending on influenza vaccination increased from € 37 million in 1996 to € 52 million in 2014, while relative to total healthcare expenditure it decreased from 0.069% to 0.055%. In 2014, 0.15% of healthcare expenditure and € 533 per birth was spent on vaccination programmes. Overall, for birth cohorts 1953-1992, € 5.4 thousand (95% confidence interval: 4.0-7.3) was expended per year-of-life-lost averted.

CONCLUSION

The actual costs per year-of-life gained are more favorable than estimated here since averted medical costs were not included. Although expenditure on vaccination programmes increased substantially, the contribution to overall healthcare expenditure remained small.

Adult vaccination as part of a healthy lifestyle: moving from medical intervention to health promotion

As the global population ages, there is concern about the effect of an increased proportion of older individuals on the economic sustainability of healthcare systems and the social effects of an older society. Health authorities and advocacy groups in countries at the forefront of this trend are now developing strategies to ameliorate the social and financial effects of an ageing population. There is broad agreement that for both society and for the individuals, it is important to ensure that increasing lifespans are matched with increased "healthspans" - the number of years spent in good health. There is also growing consensus that vaccination is one of the tools that can play an important role in improving adult health - though currently vaccination coverage is often poor. This review focuses on two issues that consistently appear to be associated with under-vaccination: the low awareness of risk (and potential consequences) for vaccine-preventable diseases and a poor understanding of the value of improved vaccination coverage for adults. We suggest that understanding of vaccination as a health-promoting activity, rather than a medical intervention designed to prevent the spread of a specific pathogen - is a crucial step to improve vaccination uptake among adults (see Supplementary video abstract ). Key messages As populations age globally, we are seeing an increasing burden of vaccine-preventable disease in adults. Adult vaccination against some common diseases has been shown to dramatically improve health and quality of life for older people. Despite the attested benefits, vaccination coverage is almost always poor in adults, even in countries where access is free at point of care. In this article, we discuss what appears to a neglected issue in adult vaccination, that of personal autonomy. We argue that adult vaccination will only be successful if it respects individual autonomy and that this requires treating the choice to vaccinate as a public health issue akin to smoking cessation, exercise and healthy diet.

Estimating the Population-Level Effectiveness of Vaccination Programs in the Netherlands

BACKGROUND

There are few estimates of the effectiveness of long-standing vaccination programs in developed countries. To fill this gap, we investigate the direct and indirect effectiveness of childhood vaccination programs on mortality at the population level in the Netherlands.

METHODS

We focused on three communicable infectious diseases, diphtheria, pertussis, and poliomyelitis, for which we expect both direct and indirect effects. As a negative control, we used tetanus, a noncommunicable infectious disease for which only direct effects are anticipated. Mortality data from 1903 to 2012 were obtained from Statistics Netherlands. Vaccination coverage data were obtained from various official reports. For the birth cohorts 1903 through 1975, all-cause and cause-specific childhood mortality burden was estimated using restricted mean lifetime survival methods, and a model was used to describe the prevaccination decline in burden. By projecting model results into the vaccination era, we obtained the expected burden without vaccination. Program effectiveness was estimated as the difference between observed and expected mortality burden.

RESULTS

Each vaccination program showed a high overall effectiveness, increasing to nearly 100% within 10 birth cohorts. For diphtheria, 14.9% (95% uncertainty interval [UI] = 12.3%, 17.6%) of mortality burden averted by vaccination was due to indirect protection. For pertussis, this was 32.1% (95% UI = 31.3%, 32.8%). No indirect effects were observed for poliomyelitis or tetanus with -2.4% (UI = -16.7%, 7.1%) and 0.6% (UI = -17.9%, 10.7%), respectively.

CONCLUSION

Vaccination programs for diphtheria and pertussis showed substantial indirect effects, providing evidence for herd protection.

Using feeding to reduce pain during vaccination of formula-fed infants: a randomised controlled trial

OBJECTIVES

To assess the effectiveness and potential side effects of formula feeding to reduce pain during vaccination among infants.

STUDY DESIGN

In the setting of well-baby clinics we recruited a community-based sample of full-term born infants who were already formula fed by the choice of the parents (n=48, aged 4-10 weeks) and received their first DTaP-IPV-HepB-Hib and pneumococcal vaccinations and randomised them into two groups. To evaluate pain experienced during vaccination we compared infants who drank formula feeding before, during and after vaccination with infants who did not. Outcomes were observed cry duration and pain scores measured by means of the Neonatal Infant Pain Scale (NIPS) and the Face, Legs, Activity, Cry and Consolability (FLACC) scale. Side effects of drinking during vaccination were recorded. We performed intention-to-treat analyses using regression models, crude and adjusted for sex and age of the infant.

RESULTS

Pain at the moment of the second injection did not differ between groups. Drinking infants cried 33.5 s shorter (-56.6; -10.3). In the first minute after injection drinking infants experienced a faster pain reduction on the NIPS_Δt: regression coefficient 3.86 (95% CI 2.70 to 5.02) and FLACC_Δt: 4.42 (95% CI 2.85 to 5.99).

CONCLUSIONS

In line with findings of previous studies regarding breast feeding, formula feeding reduced vaccination pain in the recovery phase in full-term born infants receiving their first vaccinations between ages 4 and 10 weeks with no adverse effects. Professionals should discuss this non-costly and feasible pain-reducing intervention with parents of infants who receive vaccinations.

TRIAL REGISTRATION NUMBER

IRCTN 31383, post-results.

Studies into the mechanism of measles-associated immune suppression during a measles outbreak in the Netherlands

Measles causes a transient immune suppression, leading to increased susceptibility to opportunistic infections. In experimentally infected non-human primates (NHPs) measles virus (MV) infects and depletes pre-existing memory lymphocytes, causing immune amnesia. A measles outbreak in the Dutch Orthodox Protestant community provided a unique opportunity to study the pathogenesis of measles immune suppression in unvaccinated children. In peripheral blood mononuclear cells (PBMC) of prodromal measles patients, we detected MV-infected memory CD4⁺ and CD8⁺ T cells and naive and memory B cells at similar levels as those observed in NHPs. In paired PBMC collected before and after measles we found reduced frequencies of circulating memory B cells and increased frequencies of regulatory T cells and transitional B cells after measles. These data support our immune amnesia hypothesis and offer an explanation for the previously observed long-term effects of measles on host resistance. This study emphasises the importance of maintaining high measles vaccination coverage.

The mechanisms by which measles virus infection induces transient immune suppression in humans are poorly understood. Here, Laksono and colleagues characterise the pathogenesis of measles-associated immune suppression in unvaccinated children, and shed new light on the long-term effects of measles on the host.

Immunogenicity and Safety of Monovalent Acellular Pertussis Vaccine at Birth: A Randomized Clinical Trial

IMPORTANCE

An alternative option to maternal vaccination to prevent severe pertussis in infants is vaccination at birth. Data are needed on the immunogenicity and safety of a birth dose of monovalent acellular pertussis (aP) vaccine.

OBJECTIVE

To compare IgG antibody responses to vaccine antigens at 6, 10, 24, and 32 weeks of age between newborn infants receiving the aP vaccine and hepatitis B vaccine (HBV) or HBV alone.

DESIGN, SETTING, AND PARTICIPANTS

A randomized clinical trial was conducted at 4 sites in Australia (Sydney, Melbourne, Adelaide, and Perth) between June 11, 2010, and March 14, 2013, among 440 healthy term (>36 weeks' gestation) infants aged less than 5 days at recruitment. Statistical analysis was performed from March 1, 2015, to June 2, 2016.

INTERVENTION

Newborns received HBV and, after stratification by maternal receipt of adult-formulated aP-containing vaccine (tetanus toxoid, reduced diphtheria toxoid, and pertussis antigen content [Tdap]) prior to pregnancy, were block randomized to receive the aP vaccine (without diphtheria or tetanus) within 5 days of birth or not. At 6, 16, and 24 weeks, infants received a hexavalent vaccine with pediatric-formulated diphtheria, tetanus and pertussis antigens (DTaP), Haemophilus influenzae type b (Hib), HBV, and polio vaccine, as well as the 10-valent pneumococcal conjugate vaccine.

MAIN OUTCOMES AND MEASURES

Detectable (>5 enzyme-linked immunosorbent assay units per milliliter) and geometric mean concentrations of IgG antibody to pertussis toxin (PT), pertactin, and filamentous hemagglutinin at 6, 10, and 24 weeks stratified by maternal Tdap history, and antibody at 32 weeks to HBV, Hib, polio, diphtheria, tetanus, and pneumococcal serotypes. The primary outcome was detectable IgG to both PT and pertactin at 10 weeks.

RESULTS

A total of 440 infants (207 girls and 233 boys; median gestation, 39.2 weeks) were randomized to receive the aP vaccine plus HBV (n = 221) or HBV only (control group; n = 219). At 10 weeks, 192 of 206 infants who received the aP vaccine (93.2%) had detectable antibodies to both PT and pertactin vs 98 of 193 infants in the control group (50.8%) (P < .001), with the geometric mean concentration for PT IgG 4-fold higher among the group that received the aP vaccine. At age 32 weeks, all infants (n = 181 with sera available for testing) who received the aP vaccine at birth had detectable PT IgG and significantly lower IgG geometric mean concentrations for Hib, hepatitis B, diphtheria, and tetanus antibodies. Local and systemic adverse events were similar between both groups at all time points.

CONCLUSIONS AND RELEVANCE

The monovalent aP vaccine is immunogenic and safe in neonates and, if licensed and available, would be valuable for newborns whose mothers did not receive the Tdap vaccine during pregnancy.

TRIAL REGISTRATION

http://anzctr.org.au Identifier: ACTRN12609000905268.

Years of Life Lost Due to Influenza-Attributable Mortality in Older Adults in the Netherlands: A Competing-Risks Approach

We estimated the influenza mortality burden in adults aged 60 years or older in the Netherlands in terms of years of life lost, taking into account competing mortality risks. Weekly laboratory surveillance data for influenza and other respiratory pathogens and weekly extreme temperature served as covariates in Poisson regression models fitted to weekly mortality data, specific to age group, for the period 1999-2000 through 2012-2013. Burden for age groups 60-64 years through 85-89 years was computed as years of life lost before age 90 (YLL90), using restricted mean lifetime survival analysis and accounting for competing risks. Influenza-attributable mortality burden was greatest for persons aged 80-84 years, at 914 YLL90 per 100,000 persons (95% uncertainty interval: 867, 963), followed by persons aged 85-89 years (787 YLL90/100,000; 95% uncertainty interval: 741, 834). Ignoring competing mortality risks in the computation of influenza-attributable YLL90 would lead to substantial overestimation of burden, from 3.5% for persons aged 60-64 years to 82% for those aged 80-89 years at death. Failure to account for competing mortality risks has implications for the accuracy of disease-burden estimates, especially among persons aged 80 years or older. Because the mortality burden borne by the elderly is notably high, prevention initiatives may benefit from being redesigned to more effectively prevent infection in the oldest age groups.

Trends and inequalities in the burden of mortality in Scotland 2000-2015

BACKGROUND

Cause-specific mortality trends are routinely reported for Scotland. However, ill-defined deaths are not routinely redistributed to more precise and internationally comparable categories nor is the mortality reported in terms of years of life lost to facilitate the calculation of the burden of disease. This study describes trends in Years of Life Lost (YLL) for specific causes of death in Scotland from 2000 to 2015.

METHODS

We obtained records of all deaths in Scotland by age, sex, area and underlying cause of death between 2000 and 2015. We redistributed Ill-Defined Deaths (IDDs) to more exact and meaningful causes using internationally accepted methods. Years of Life Lost (YLL) using remaining life expectancy by sex and single year of age from the 2013 Scottish life table were calculated for each death. These data were then used to calculate the crude and age-standardised trends in YLL by age, sex, cause, health board area, and area deprivation decile.

RESULTS

Between 2000 and 2015, the annual percentage of deaths that were ill-defined varied between 10% and 12%. The proportion of deaths that were IDDs increased over time and were more common: in women; amongst those aged 1-4 years, 25-34 years and >80 years; in more deprived areas; and in the island health boards. The total YLL fell from around 17,800 years per 100,000 population in 2000 to around 13,500 years by 2015. The largest individual contributors to YLL were Ischaemic Heart Disease (IHD), respiratory cancers, Chronic Obstructive Pulmonary Disease (COPD), cerebrovascular disease and Alzheimer's/dementia. The proportion of total YLL due to IHD and stroke declined over time, but increased for Alzheimer's/dementia and drug use disorders. There were marked absolute inequalities in YLL by area deprivation, with a mean Slope Index of Inequality (SII) for all causes of 15,344 YLL between 2001 and 2015, with IHD and COPD the greatest contributors. The Relative Index of Inequality (RII) for YLL was highest for self-harm and lower respiratory infections.

CONCLUSION

The total YLL per 100,000 population in Scotland has declined over time. The YLL in Scotland is predominantly due to a wide range of chronic diseases, substance misuse, self-harm and increasingly Alzheimer's disease and dementia. Inequalities in YLL, in both relative and absolute terms, are stark.

Heterogeneity Between States in the Health and Economic Impact of Measles Immunization in the United States

Background

Vaccines have been used successfully for disease elimination programs in many countries. Evidence on the impact of vaccination programs can support decision-making among medical practitioners and policy makers to improve immunization rates. We estimated the health and economic impact of measles vaccination for each of the 48 contiguous states and the District of Columbia since 1964.

Methods

For each state, we fitted multiple time-series models to prevaccination data and used the best-fitting model to predict counterfactual cases that would have occurred in the absence of vaccination. We then subtracted observed from counterfactual measles cases, deaths, and related costs to estimate the impact of vaccination.

Results

We estimated that 149 million children were vaccinated against measles in the United States between 1964 and 2014, at a cost of $12.2 billion, and that vaccination prevented 29.8 million cases, 32 000 deaths, and $25.8 billion in societal costs. The impact exceeded the national average in 70% of Western and Northeastern states, compared with only 24% of Southern and Midwestern states.

Conclusions

The significant health and economic benefit of measles vaccination in the United States should encourage continued investments to sustain and expand vaccination programs globally.

Methodology for computing the burden of disease of adverse events following immunization

Purpose

Composite disease burden measures such as disability‐adjusted life‐years (DALY) have been widely used to quantify the population‐level health impact of disease or injury, but application has been limited for the estimation of the burden of adverse events following immunization. Our objective was to assess the feasibility of adapting the DALY approach for estimating adverse event burden.

Methods

We developed a practical methodological framework, explicitly describing all steps involved: acquisition of relative or absolute risks and background event incidence rates, selection of disability weights and durations, and computation of the years lived with disability (YLD) measure, with appropriate estimation of uncertainty. We present a worked example, in which YLD is computed for 3 recognized adverse reactions following 3 childhood vaccination types, based on background incidence rates and relative/absolute risks retrieved from the literature.

Results

YLD provided extra insight into the health impact of an adverse event over presentation of incidence rates only, as severity and duration are additionally incorporated. As well as providing guidance for the deployment of DALY methodology in the context of adverse events associated with vaccination, we also identified where data limitations potentially occur.

Conclusions

Burden of disease methodology can be applied to estimate the health burden of adverse events following vaccination in a systematic way. As with all burden of disease studies, interpretation of the estimates must consider the quality and accuracy of the data sources contributing to the DALY computation.

Quantifying the impact of mass vaccination programmes on notified cases in the Netherlands

Vaccination programmes are considered a main contributor to the decline of infectious diseases over the 20th century. In recent years, the national vaccination coverage in the Netherlands has been declining, highlighting the need for continuous monitoring and evaluation of vaccination programmes. Our aim was to quantify the impact of long-standing vaccination programmes on notified cases in the Netherlands. We collected and digitised previously unavailable monthly case notifications of diphtheria, poliomyelitis, mumps and rubella in the Netherlands over the period 1919-2015. Poisson regression models accounting for seasonality, multi-year cycles, secular trends and auto-correlation were fit to pre-vaccination periods. Cases averted were calculated as the difference between observed and expected cases based on model projections. In the first 13 years of mass vaccinations, case notifications declined rapidly with 82.4% (95% credible interval (CI): 74.9-87.6) of notified cases of diphtheria averted, 92.9% (95% CI 85.0-97.2) cases of poliomyelitis, and 79.1% (95% CI 67.1-87.4) cases of mumps. Vaccination of 11-year-old girls against rubella averted 49.9% (95% CI 9.3-73.5) of cases, while universal vaccination averted 68.1% (95% CI 19.4-87.3) of cases. These findings show that vaccination programmes have contributed substantially to the reduction of infectious diseases in the Netherlands.

Pertussis surveillance and control: exploring variations and delays in testing, laboratory diagnostics and public health service notifications, the Netherlands, 2010 to 2013

Pertussis is most severe among unvaccinated infants (< 1 year of age), and still leads to several reported deaths in the Netherlands every year. In order to avoid pertussis-related infant morbidity and mortality, pertussis surveillance data are used to guide pertussis control measures. However, more insight into the accuracy of pertussis surveillance and control, and into the range of healthcare and public health-related factors that impede this are needed. We analysed a unique combination of data sources from one Dutch region of 1.1 million residents, including data from laboratory databases and local public health notifications between 2010 and 2013. This large study (n = 12,090 pertussis tests) reveals possible misdiagnoses, substantial under-notification (18%, 412/2,301 laboratory positive episodes) and a delay between patient symptoms and notification to the local public health services (median 34 days, interquartile range (IQR): 27–54). It is likely that the misdiagnoses, under-notification and overall delay in surveillance data are not unique to this area of the Netherlands, and are generalisable to other countries in Europe. In addition to preventive measures such as maternal immunisation, based on current findings, we further recommend greater adherence to testing guidelines, standardisation of test interpretation guidelines, use of automatic notification systems and earlier preventive measures.

Global Childhood Deaths From Pertussis: A Historical Review

Impact of pertussis vaccines on mortality is a key World Health Organization indicator, and trends in mortality rates and age distribution can inform maternal immunization strategies. We systematically reviewed studies reporting pertussis mortality rates (PMRs) per million population, identifying 19 eligible studies. During a prevaccine observation period of ≥50 years in high-income countries (HICs), PMRs reduced in both infants and 1- to 4-year-olds by >80%, along with improvements in living conditions. In studies in low- and middle-income countries (LMICs), PMRs resembled highest prevaccine HIC rates. Postvaccine in HICs, significant further reduction in deaths (>98%) occurred, but with a large left shift in age of onset among residual deaths. Postvaccine in LMICs, limited data also show large and rapid decreases in PMRs, first in older infants and children, but long-term data fully enumerating residual deaths are lacking. In Sweden, large increases in the prevalence of undetectable pertussis antibodies were found at 10 years after high childhood coverage of acellular pertussis vaccines. Such data are not available from LMICs using whole-cell vaccines in a primary schedule without boosters. Data on residual infant deaths and maternal seroprevalence would be valuable inputs into consideration of pertussis vaccination in pregnancy in LMIC settings, especially if more precise immune correlates of infant protection against death from pertussis were known.

Non-specific effects of measles, mumps, and rubella (MMR) vaccination in high income setting: population based cohort study in the Netherlands

Objectives To investigate whether measles, mumps, and rubella (MMR) vaccine has positive non-specific effects in a high income setting and to compare rates of hospital admissions for infections between children aged ≤2 years who received live MMR vaccine and those who received an inactivated vaccine against diphtheria, tetanus, pertussis, polio, and Haemophilus influenzae type b (DTaP-IPV-Hib) as their most recent vaccination.Design Nationwide population based cohort study.Setting In the Netherlands, DTaP-IPV-Hib+pneumococcal vaccination (PCV) is recommended at ages 2, 3, 4, and 11 months and MMR + meningococcal C (MenC) vaccination at age 14 months. Data from the national vaccine register were linked to hospital admission data.Participants 1 096 594 children born in 2005-11 who received the first four DTaP-IPV-Hib+PCV vaccines.Main outcome measures Hazard ratio for admission to hospital for infection in children with MMR+MenC compared with the fourth DTaP-IPV-Hib+PCV as their most recent vaccination. Cox regression was performed with most recent vaccination as time dependent variable, adjusted for potential confounders. Analyses were repeated with admission for injuries or poisoning as a negative control outcome. In addition, rate of admission for infection was compared between the fourth and third DTaP-IPV-Hib+PCVas most recent vaccination.Results Having had MMR+MenC as the most recent vaccination was associated with a hazard ratio of 0.62 (95% confidence interval 0.57 to 0.67) for admission to hospital for infection and 0.84 (0.73 to 0.96) for injuries or poisoning, compared with the fourth DTaP-IPV-Hib+PCV as most recent vaccination. The fourth DTaP-IPV-Hib+PCV as most recent vaccination was associated with a hazard ratio of 0.69 (0.63 to 0.76) for admission to hospital for infection, compared with the third DTaP-IPV-Hib+PCV as most recent vaccination.Conclusions Healthy vaccinee bias could at least partly explain the observed lower rate of admission to hospital with infection after MMR vaccination. The lower rate is associated with receipt of any additional vaccine, not specifically MMR vaccine. This emphasises the caution required in the interpretation of findings from observational studies on non-specific effects of vaccination.

We strongly support childhood immunisation-statement from the European Academy of Paediatrics (EAP)

The eradication of smallpox and the elimination of several other infectious diseases from much of the world has provided convincing evidence that vaccines are among the most effective interventions for promoting health. The current scepticism about immunisation among members of the new US administration carries a risk of decreasing immunisation rates also in Europe. While only a small minority of the population are strongly anti-vaccine, their public activities have significantly influenced an uncertainty among the general population about both the safety of and the necessity for vaccination. Therefore, the EAP calls for greater publically available, scientifically supported information on vaccination, particularly targeted at health care providers, for the further development of electronically based immunisation information systems (IIS). We further call on all European countries to work together both in legislative and public health arenas in order to increase vaccination coverage among the paediatric population. In the interest of children and their parents, the EAP expresses its strong support for childhood immunisation and recommended vaccination schedules. We are prepared to work with governments and media and share the extensive evidence demonstrating the effectiveness and safety of vaccines.

Tetanus-diphtheria-acellular pertussis vaccination for adults: an update

Although tetanus and diphtheria have become rare in developed countries, pertussis is still endemic in some developed countries. These are vaccine-preventable diseases and vaccination for adults is important to prevent the outbreak of disease. Strategies for tetanus, diphtheria, and pertussis vaccines vary from country to country. Each country needs to monitor consistently epidemiology of the diseases and changes vaccination policies accordingly. Recent studies showed that tetanus–diphtheria–acellular pertussis vaccine for adults is effective and safe to prevent pertussis disease in infants. However, vaccine coverage still remains low than expected and seroprevalence of protective antibodies levels for tetanus, diphtheria, and pertussis decline with aging. The importance of tetanus–diphtheria–acellular pertussis vaccine administration should be emphasized for the protection of young adult and elderly people also, not limited to children.