Examining a possible association between human papilloma virus (HPV) vaccination and migraine: results of a cohort study in the Netherlands

Since the introduction of the bivalent human papilloma virus (HPV) vaccine in the Netherlands, migraine has been reported as a notable event in the passive safety surveillance system. Research on the association between HPV vaccination and migraine is needed. Therefore, potential migraine cases in 2008–2010 were selected from a group of general practitioners and linked to the vaccination registry. Data were analysed in three ways: (i) incidences of migraine postvaccination (2009/2010) were compared to pre-vaccination incidences (2008); (ii) in a cohort, incidence rates of migraine in vaccinated and unvaccinated girls were compared and (iii) in a self-controlled case series analysis, the relative incidence of migraine in potentially high-risk periods was compared to non-high-risk periods. Incidence rates of migraine for 12- to 16-year-old girls and boys postvaccination were slightly higher than pre-vaccination incidence rates. Incidence rate ratios (IRRs) for vaccinated compared to unvaccinated girls were not statistically significantly higher. Furthermore, the RR for migraine in the high-risk period of 6 weeks following each dose versus non-high-risk period was 4.3 (95% confidence interval (CI) 0.69–26.6) for certain migraine. Conclusion: Using different methods, no statistically significant association between HPV vaccination and incident migraine was found. However, the number of cases was low; to definitively exclude the risk, an increased sample size is needed

Epidemic of mumps among vaccinated persons, the Netherlands, 2009-2012

To analyze the epidemiology of a nationwide mumps epidemic in the Netherlands, we reviewed 1,557 notified mumps cases in persons who had disease onset during September 1, 2009-August 31, 2012. Seasonality peaked in sprin

Additional evidence on serological correlates of protection against measles: An observational cohort study among once vaccinated children exposed to measles

To assess correlates of protection against measles and against subclinical measles virus (MV) infection, we recruited once-vaccinated children from geographic regions associated with increased MV circulation and/or at schools with low vaccination coverage in the Netherlands. Paired blood samples were collected shortly after onset of the measles outbreak and after the outbreak. A questionnaire was used to document the likelihood of exposure to MV and occurrence of measles-like symptoms. All blood samples were tested for MV-specific antibodies with five different assays. Correlates of protection were assessed by considering the lowest neutralizing antibody levels in children without MV infection, and by ROC analyses. Among 91 participants, two seronegative children (2%) developed measles, and an additional 19 (23%) experienced subclinical MV infection. The correlate of protection against measles was lower than 0.345 IU/mL. We observed a decreasing attack rate of subclinical MV infection with increasing levels of specific antibodies until 2.1 IU/mL, above which no subclinical MV infections were detected. The ROC analyses found a correlate of protection of 1.71 IU/mL (95% CI 1.01–2.11) for subclinical MV infection. Our correlates of protection were consistent with previous estimates. This information supports the analyses of serosurveys to detect immunity gaps that require targeted intervention strategies

No evidence found for an increased risk of long-term fatigue following human papillomavirus vaccination of adolescent girls

METHODS: In this retrospective cohort study conducted in the Integrated Primary Care Information database, we investigated the occurrence of chronic fatigue syndrome (CFS), fatigue ≥6 months and 3-6 months in all girls born in 1991-2000 during the follow-up period January 1st 2007-December 31st 2014 (2007-2008 pre-vaccination and 2009-2014 post-vaccination). Patients with certain fatigue ≥6 m were asked for consent to link their primary care information with vaccination data. Incidence rates per 10,000 person years (PY) for 12-16-year-old girls were compared between pre- and post-HPV-vaccine era. A self-controlled case series (SCCS) analysis was performed using consenting vaccinated cases. A primary high-risk period of 12 months after each dose was defined.CONCLUSIONS: Fatigue ≥6 m and 3-6 m was frequently found among adolescent girls, but CFS was rarely diagnosed. No statistically significant increased incidence rates were found post-vaccination compared to similar age groups of girls pre-vaccination. The SCCS analysis included a low number of cases but revealed no elevated risk of certain fatigue ≥6 m in the high-risk period.RESULTS: The cohort consisted of 69,429 12-16-year-old girls accounting for 2758 PY pre-vaccination and 57,214 PY post-vaccination. Differences between pre- and post-vaccination incidences (CFS: 3.6 (95% CI 0.5-25.7)/10,000 PY and 0.9 (0.4-2.1); certain fatigue ≥6 m: 7.3 (1.8-29.0) and 19.4 (16.1-23.4); certain fatigue 3-6 m: 0.0 and 16.6 (13.6-20.3), respectively) were not statistically significant. SCCS analyses in 16 consenting vaccinated cases resulted in an age-adjusted RR of 0.62 (95%CI 0.07-5.49).INTRODUCTION: In 2013, the Netherlands Pharmacovigilance Center Lareb published an overview of reports of long-lasting fatigue following bivalent HPV-vaccination (2vHPV). After an update of this overview in 2015, concerns regarding the safety of 2vHPV was picked up by the media, which led to further reports of long-lasting fatigue. Therefore, the Dutch National Institute for Public Health and the Environment (RIVM) investigated a possible association between HPV-vaccination and long-term fatigue

International collaboration to assess the risk of Guillain Barre Syndrome following Influenza A (H1N1) 2009 monovalent vaccines

<p>Background: The global spread of the 2009 novel pandemic influenza A (H1N1) virus led to the accelerated production and distribution of monovalent 2009 Influenza A (H1N1) vaccines (pH1N1). This pandemic provided the opportunity to evaluate the risk of Guillain-Barre syndrome (GBS), which has been an influenza vaccine safety concern since the swine flu pandemic of 1976, using a common protocol among high and middle-income countries. The primary objective of this project was to demonstrate the feasibility and utility of global collaboration in the assessment of vaccine safety, including countries both with and without an established infrastructure for vaccine active safety surveillance. A second objective, included a priori, was to assess the risk of GBS following pH1N1 vaccination.</p><p>Methods: The primary analysis used the self-controlled case series (SCCS) design to estimate the relative incidence (RI) of GBS in the 42 days following vaccination with pH1N1 vaccine in a pooled analysis across databases and in analysis using a meta-analytic approach.</p><p>Results: We found a relative incidence of GBS of 2.42(95% CI 1.58-3.72) in the 42 days following exposure to pH1N1 vaccine in analysis of pooled data and 2.09(95% CI 1.28-3.42) using the meta-analytic approach.</p><p>Conclusions: This study demonstrates that international collaboration to evaluate serious outcomes using a common protocol is feasible. The significance and consistency of our findings support a conclusion of an association between 2009 H1N1 vaccination and GBS. Given the rarity of the event the relative incidence found does not provide evidence in contradiction to international recommendations for the continued use of influenza vaccines. (C) 2013 Elsevier Ltd. All rights reserved.</p>