Incidence of narcolepsy before and after MF59-adjuvanted influenza A(H1N1)pdm09 vaccination in South Korean soldiers

BackgroundPrevious reports mostly from Europe suggested an association between an occurrence of narcolepsy and an influenza A(H1N1)pdm09 vaccine adjuvanted with AS03 (Pandemrix^®). During the 2009 H1N1 pandemic vaccination campaign, the Korean military performed a vaccination campaign with one type of influenza vaccine containing MF59-adjuvants. This study was conducted to investigate the background incidence rate of narcolepsy in South Korean soldiers and the association of the MF59-adjuvanted vaccine with the occurrence of narcolepsy in a young adult group.MethodsTo assess the incidence of narcolepsy, we retrospectively reviewed medical records of suspicious cases of narcolepsy in 2007–2013 in the whole 20 military hospitals of the Korean military. The screened cases were classified according to the Brighton Collaboration case definition of narcolepsy. After obtaining the number of confirmed cases of narcolepsy per 3 months in 2007–2013, we compared the crude incidence rate of narcolepsy before and after the vaccination campaign.ResultsWe included 218 narcolepsy suspicious cases in the initial review, which were screened by the diagnostic code on the computerized disease registry in 2007–2013. Forty-one cases were finally diagnosed with narcolepsy in 2007–2013 (male sex, 95%; median age, 21 years). The average background incidence rate of narcolepsy in Korean soldiers was 0.91 cases per 100,000 persons per year. During the 9 months before vaccination implementation (April to December 2009), 6 narcolepsy cases occurred, whereas during the next 9 months (January to September 2010) including the 3-month vaccination campaign, 5 cases occurred.ConclusionsThe incidence of narcolepsy in South Korean soldiers was not increased after the pandemic vaccination campaign using the MF59-adjuvanted vaccine. Our results suggest that the MF59-adjuvanted H1N1 vaccine did not contribute to the occurrence of narcolepsy in this young adult group.     

Spontaneous reports of vaccination errors in the European regulatory database EudraVigilance: A descriptive study

BackgroundAmong all post-marketing medication error reports submitted to EudraVigilance, vaccines are the most frequently reported medicinal products. This study aims to describe the characteristics of vaccination errors submitted to Eudravigilance between 2001 and 2016.MethodsEudraVigilance is a spontaneous reporting database for adverse events maintained by the European Medicines Agency. We extracted Individual Case Safety Reports (ICSRs) submitted to EudraVigilance between 1 January 2001 and 31 December 2016. Reports were included for analysis if a vaccine was reported as interacting or suspect drug and at least one medication error term was listed as an adverse reaction. ICSRs were stratified by age and gender, by year of reporting, region of origin, reporter profession, seriousness of outcome, ATC, and type of error.ResultsIn total, 7097 ICSRs were included in the study. We observed a yearly increase in the reporting of vaccination errors, with the proportion to all vaccine ICSRs increasing from 0.4% to 4.0% between 2001 and 2016. The majority of reports was classified as serious (4248, 59.9%), but non-serious reports were increasingly reported since 2012. The mean age of patients was 24.1 years. The most frequently reported vaccines were influenza (13.5%), bacterial and viral combined (12.3%), and hepatitis vaccines (11.8%). A total of 8167 medication error terms were reported. The most frequently reported terms were “Inappropriate schedule of drug administration” (27.2%), “Incorrect route of drug administration” (12.5%) and “Drug administered to patient of inappropriate age” (10.0%). For infants and children, the error “Drug administered to patient of inappropriate age” was reported more often than for all other age categories.DiscussionVaccination errors are increasingly submitted to EudraVigilance. Errors related to the schedule are the most common errors reported with vaccines. However, consequences of vaccination errors appear to be relatively mild.     

Estimating the number of averted illnesses and deaths as a result of vaccination against an influenza pandemic in nine low- and middle-income countries

BackgroundDuring the 2009 influenza A(H1N1)pdm09 pandemic, 77 countries received donated monovalent A(H1N1)pdm09 vaccine through the WHO Pandemic Influenza A(H1N1) Vaccine Deployment Initiative. However, 47% did not receive their first shipment until after the first wave of virus circulation, and 8% did not receive their first shipment until after the WHO declared the end of the pandemic. Arguably, these shipments were too late into the pandemic to have a substantial effect on virus transmission or disease burden during the first waves of the pandemic.ObjectivesIn order to evaluate the potential benefits of earlier vaccine availability, we estimated the number of illnesses and deaths that could be averted during a 2009-like influenza pandemic under five different vaccine-availability timing scenarios.MethodsWe adapted a model originally developed to estimate annual influenza morbidity and mortality burden averted through US seasonal vaccination and ran it for five vaccine availability timing scenarios in nine low- and middle-income countries that received donated vaccine.ResultsAmong nine study countries, we estimated that the number of averted cases was 61–216,197 for actual vaccine receipt, increasing to 2,914–283,916 had vaccine been available simultaneously with the United States.ConclusionsEarlier delivery of vaccines can reduce influenza case counts during a simulated 2009-like pandemic in some low- and middle-income countries. For others, increasing the number of cases and deaths prevented through vaccination may be dependent on factors other than timely initiation of vaccine administration, such as distribution and administration capacity.     

Fatal outcomes following immunization errors as reported to the EudraVigilance: A case series

BackgroundSerious adverse reactions after immunization are rare but do occur. In very rare instances, cases with fatal outcome have been reported. These reports can have a huge impact and even more so when due to an immunization error. The aim of this study is to systematically review immunization errors with fatal outcomes in EudraVigilance.MethodsThis was a case-series analysis of Individual Case Safety Reports (ICSRs) reporting immunization errors and a fatal outcome. To determine the level of certainty of a causal association between the immunization errors and fatal outcomes two independent reviewers assessed all ICSRs using the WHO tool “Causality assessment of an Adverse Event Following Immunization (AEFI)”. In accordance with the tool, the ICSRs were classified as consistent, indeterminate, inconsistent/coincidental, or unclassifiable. In addition, we estimated the contribution of reported errors to the fatal outcomes as large, moderate, small, none, or unclassifiable using a classification developed for this study.ResultsA total of 154 ICSRs met the inclusion criteria. Vaccines reported most frequently were pneumococcal (33), rabies (27) and influenza vaccines (24). Most frequently reported errors were non-compliance with recommended schedules of immunization (63). The most frequently reported vaccine-error combination was rabies vaccines and non-compliance with a recommended schedule of immunization (23). Twelve cases were classified as consistent with causal association and had a large error contribution. These cases concerned a cluster of six cases reporting incorrect handling of multi-dose vials containing measles vaccine and six cases reporting administration of live-attenuated vaccines to immunocompromised patients.DiscussionIn this study, we showed that fatal outcomes following immunization errors are very rare. Four key issues were the importance of: (1) quality control of multi-dose vaccines, (2) screening patients for immunocompromising factors, (3) education on the importance of adherence, and (4) measures to improve distinction between vaccines and medicines.     

An algorithm developed using the Brighton Collaboration case definitions is more efficient for determining diagnostic certainty

The Brighton Collaboration is a global research network focused on vaccine safety. The Collaboration has created case definitions to determine diagnostic certainty for several adverse events. Currently nested within multi-page publications, these definitions can be cumbersome for use. We report the results of a randomized trial in which the case definition for anaphylaxis was converted into a user-friendly algorithm and compared the algorithm with the standard case definition. The primary outcomes were efficiency and accuracy. Forty medical students determined the Brighton Level of diagnostic certainty of a sample case of anaphylaxis using either the algorithm or the original case definition. Most participants in both groups selected the correct Brighton Level. Participants using the algorithm required significantly less time to review the case and determine the level of diagnostic certainty [mean difference = 107 s (95% CI: 13–200; p = 0.026)], supporting that the algorithm was more efficient without impacting accuracy.     

Italian post-marketing surveillance for adverse event reports after MF59-adjuvanted H1N1v vaccination

According to European recommendations, the Italian Medicines Agency (AIFA) required close monitoring of the safety of the MF59-adjuvanted H1N1v vaccine, which was the only vaccine available in Italy for prophylaxis of the A/H1N1 (2009) pandemic influenza. From October 2009 to June 2010, the Italian Pharmacovigilance Adverse Event (AE) Spontaneous Reporting System [Rete Nazionale Farmacovigilanza] (RNF) received 1330 reports of AEs temporally related with the pandemic influenza vaccination out of a total of 924,057 doses administered. Among these, 1,162 (87.37%) AE reports were classified ‘non serious’, 91 (6.84%) ‘serious’, 3 (0.23%) had a fatal outcome and 74 (5.56%) did not include the degree of seriousness. Among the serious AE reports, some unexpected AEs emerged. Even though some typical vaccine safety issues which emerged should be further explored, such as vaccination in pregnancy, the analysis of all AE reports sent to RNF shows that the vaccine has a well-tolerated safety profile which resembles that of the already available seasonal influenza vaccines. This contrasts with the widespread public concern about its safety, which has been one of the major causes of the low vaccination rate observed in Italy, as well as in other countries.     

Narcolepsy and hypersomnia in Norwegian children and young adults following the influenza A(H1N1) 2009 pandemic

BackgroundAssociations between influenza infection and sleep disorders are poorly studied. We investigated if pandemic influenza infection or vaccination with Pandemrix in 2009/2010 was associated with narcolepsy or hypersomnia in children and young adults.MethodsWe followed the Norwegian population under age 30 from January 2008 through December 2012 by linking national health registry data. Narcolepsy diagnoses were validated using hospital records. Risks of narcolepsy or hypersomnia were estimated as adjusted hazard ratios (HRs) in Cox regression models with influenza infection and vaccination as time-dependent exposures.ResultsAmong the 1,638,526 persons under age 30 in Norway in 2009, 3.6% received a physician diagnosis of influenza during the pandemic, while 41.9% were vaccinated against pandemic influenza. Between October 1st 2009 and December 31st 2012, 72 persons had onset of narcolepsy and 305 were diagnosed with hypersomnia. The risk of a sleep disorder was associated with infection during the first six months, adjusted HR 3.31 with 95% confidence interval [CI], 1.01–10.79 for narcolepsy and adjusted HR 3.13 (95% CI, 1.12–8.76) for hypersomnia. The risk of narcolepsy was strongly associated with vaccination during the first six months adjusted HR 17.21 (95% CI, 6.28–47.14), while the adjusted HR for hypersomnia was 1.54 (95% CI, 0.81–2.93).ConclusionsThe study confirms an increased HR of narcolepsy following pandemic vaccination. Slightly increased HRs of narcolepsy and hypersomnia are also seen after influenza infection. However, the role of infection should be viewed with caution due to underreporting of influenza.     

Increased risk of anaphylaxis following administration of 2009 AS03-adjuvanted monovalent pandemic A/H1N1 (H1N1pdm09) vaccine

Background

Anaphylaxis after trivalent influenza vaccination is typically reported at a rate of <1 per million doses. In Quebec, Canada, anaphylaxis following administration of the monovalent AS03-adjuvanted H1N1pdm09 vaccine was reported through passive surveillance at a rate of 8 per million doses administered. This was 20 times higher than the reporting rate for non-adjuvanted trivalent vaccines administered during the six previous seasons. However, adequate estimation of the incidence of anaphylaxis is hindered by wide variations in definitions and diagnosis.

Methods

Using the Brighton collaboration case definition of anaphylaxis, all cases with allergic symptoms (AS) reported to public health were reviewed to estimate the incidence of anaphylaxis following AS03-adjuvanted H1N1pdm09 vaccine.

Results

Among 752 reports of allergic symptoms, 33 were initially reported as anaphylaxis of which 20/33 (60%) met the Brighton definition (19/20 with certainty levels 1 or 2). A total of 38 additional cases with onset within 1 h of vaccination also met the Brighton definition of anaphylaxis (27 (71%) with certainty levels 1 or 2). The 58 cases meeting Brighton Level 1 or 2 criteria for anaphylaxis represent a 75% increase over the 33 passively reported and an incidence of 13 per million doses administered.

Conclusion

A substantial number of patients with early-onset allergic symptoms met the most specific levels of the Brighton case definition but were not reported as anaphylaxis. Based on this specific case definition, the incidence of anaphylaxis after AS03-adjuvanted H1N1pdm09 vaccine substantially exceeded that reported with seasonal influenza vaccines, a signal that warrants better understanding.     

Vaccinomics: A scoping review

BackgroundThis scoping review summarizes a key aspect of vaccinomics by collating known associations between heterogeneity in human genetics and vaccine immunogenicity and safety.MethodsWe searched PubMed for articles in English using terms covering vaccines routinely recommended to the general US population, their effects, and genetics/genomics. Included studies were controlled and demonstrated statistically significant associations with vaccine immunogenicity or safety. Studies of Pandemrix®, an influenza vaccine previously used in Europe, were also included, due to its widely publicized genetically mediated association with narcolepsy.FindingsOf the 2,300 articles manually screened, 214 were included for data extraction. Six included articles examined genetic influences on vaccine safety; the rest examined vaccine immunogenicity. Hepatitis B vaccine immunogenicity was reported in 92 articles and associated with 277 genetic determinants across 117 genes. Thirty-three articles identified 291 genetic determinants across 118 genes associated with measles vaccine immunogenicity, 22 articles identified 311 genetic determinants across 110 genes associated with rubella vaccine immunogenicity, and 25 articles identified 48 genetic determinants across 34 genes associated with influenza vaccine immunogenicity. Other vaccines had fewer than 10 studies each identifying genetic determinants of their immunogenicity. Genetic associations were reported with 4 adverse events following influenza vaccination (narcolepsy, GBS, GCA/PMR, high temperature) and 2 adverse events following measles vaccination (fever, febrile seizure).ConclusionThis scoping review identified numerous genetic associations with vaccine immunogenicity and several genetic associations with vaccine safety. Most associations were only reported in one study. This illustrates both the potential of and need for investment in vaccinomics. Current research in this field is focused on systems and genetic-based studies designed to identify risk signatures for serious vaccine reactions or diminished vaccine immunogenicity. Such research could bolster our ability to develop safer and more effective vaccines.     

Does having a seasonal influenza program facilitate pandemic preparedness? An analysis of vaccine deployment during the 2009 pandemic

BackgroundNational seasonal influenza programs have been recommended as a foundation for pandemic preparedness. During the 2009 pandemic, WHO aimed to increase Member States’ equitable access to influenza vaccines through pandemic vaccine donation.MethodsThis analysis explores whether the presence of a seasonal influenza program contributed to more rapid national submission of requirements to receive vaccine during the 2009 influenza pandemic. Data from 2009 influenza vaccine donation, deployment, and surveillance initiatives were collected during May-September 2018 from WHO archival material. Data about the presence of seasonal influenza vaccine programs prior to 2009 were gathered from the WHO-UNICEF Joint Reporting Form. Cox proportional hazards models were used to assess the relationship between presence of a seasonal influenza program and time to submission of a national deployment and vaccination plan and to vaccine delivery.FindingOf 97 countries eligible to receive WHO-donated vaccine, 83 (86%) submitted national deployment and vaccination plans and 77 (79%) received vaccine. Countries with a seasonal influenza vaccine program were more likely to submit a national deployment and vaccination plan (hazards ratio [HR] 2.1; 95% confidence interval [CI]. Countries with regulatory delays were less likely to receive vaccine than those without these delays (HR 0.4, 95% CI: 0.2–0.6).InterpretationDuring the 2009 pandemic, eligible countries with a seasonal influenza vaccine program were more ready to receive and use donated vaccines than those without a program. Our findings suggest that robust seasonal influenza vaccine programs increase national familiarity with the management of influenza vaccines and therefore enhance pandemic preparedness.FundingN/A.     

Postmarketing safety surveillance of trivalent recombinant influenza vaccine: Reports to the Vaccine Adverse Event Reporting System

On January 16, 2013, the Food and Drug Administration approved recombinant hemagglutinin influenza vaccine (RIV3) (Spodoptera frugiperda cell line; Flublok), which is the first completely egg-free flu vaccine licensed in the United States. To improve our understanding of the safety profile of this vaccine, we reviewed and summarized reports to the Vaccine Adverse Event Reporting System (VAERS) following RIV3. Through June 30, 2016, VAERS received 88 reports. Allergic reactions, including anaphylaxis, were the most common type of adverse event. Based on medical review, 10 cases met the Brighton Collaboration case definition of anaphylaxis, 21 reports described allergic reactions other than anaphylaxis, and 11 reports described signs and symptoms that suggested hypersensitivity. Other adverse events included injection site reactions, fatigue, myalgia, headache, and fever. The occurrence of anaphylaxis and other allergic reactions in some individuals may reflect an underlying predisposition to atopy that may manifest itself after an exposure to any drug or vaccine, and it does not necessarily suggest a causal relationship with the unique constituents that are specific to the vaccine product administered. Further research may elucidate the mechanism of allergic reactions following influenza vaccination: it is possible that egg proteins and influenza hemagglutinin play little or no role. Vaccination remains the single best defense against influenza and its complications. The information summarized here may enable policy makers, health officials, clinicians, and patients to make a more informed decision regarding vaccination strategies.     

Long term effectiveness of adjuvanted influenza A(H1N1)pdm09 vaccine in children

BackgroundImmunological studies have indicated that the effectiveness of AS03 adjuvanted monovalent influenza A(H1N1)pdm09 vaccine (Pandemrix^®) may be of longer duration than what is seen for non-adjuvanted seasonal influenza vaccines. Sixty-nine percent of children 6 months–18 years of age in Stockholm County received at least one dose of Pandemrix^® during the 2009 pandemic. We studied the effectiveness of the vaccine during the influenza seasons 2010–2011 and 2012–2013 in children hospitalized with virologically confirmed influenza. The season 2011–2012 was not included, since influenza A(H3N2) was the predominant circulating strain.MethodsIn a retrospective case-control study using a modified test-negative design we compared the percentage vaccinated with Pandemrix^® among children diagnosed with influenza A(H1N1)pdm09 (cases), with that of those diagnosed with influenza A(H3N2) or influenza B (controls) during the two seasons. We excluded children born after July 1, 2009, since only children who were 6 months of age or older received the pandemic vaccine in October–December 2009.ResultsDuring the 2010–2011 season, 3/16 (19%) of children diagnosed with influenza A(H1N1)pdm09, vs. 32/41 (78%) of those with influenza A(H3N2) or influenza B had been vaccinated with Pandemrix^® in 2009. The odds ratio, after adjustment for sex, age and underlying diseases, for becoming a case when vaccinated with Pandemrix^® was 0.083 (95%CI 0.014, 0.36), corresponding to a VE of 91.7%. During the season 2012–2013, there was no difference between the two groups; 59% of children diagnosed with influenza A(H3N2)/B and 60% of those with influenza A(H1N1)pdm09 had been vaccinated with Pandemrix^® in 2009.ConclusionThe AS03 adjuvanted monovalent influenza A(H1N1) pdm09 vaccine (Pandemrix^®) was effective in preventing hospital admission for influenza A(H1N1)pdm09 in children during at least two seasons.     

Safety reporting in developing country vaccine clinical trials-a systematic review

With more vaccines becoming available worldwide, vaccine research is on the rise in developing countries. To gain a better understanding of safety reporting from vaccine clinical research in developing countries, we conducted a systematic review in Medline and Embase (1989-2011) of published randomized clinical trials (RCTs) reporting safety outcomes with ≥50% developing country participation (PROSPERO systematic review registration number: CRD42012002025). Developing country vaccine RCTs were analyzed with respect to the number of participants, age groups studied, inclusion of safety information, number of reported adverse events following immunization (AEFI), type and duration of safety follow-up, use of standardized AEFI case definitions, grading of AEFI severity, and the reporting of levels of diagnostic certainty for AEFI. The systematic search yielded a total number of 50 randomized vaccine clinical trials investigating 12 different vaccines, most commonly rotavirus and malaria vaccines. In these trials, 94,459 AEFI were reported from 446,908 participants receiving 735,920 vaccine doses. All 50 RCTs mentioned safety outcomes with 70% using definitions for at least one AEFI. The most commonly defined AEFI was fever (27), followed by local (16) and systemic reactions (14). Logistic regression analysis revealed a positive correlation between the implementation of a fever case definition and the reporting rate for fever as an AEFI (p=0.027). Overall, 16 different definitions for fever and 7 different definitions for erythema were applied. Predefined AEFI case definitions by the Brighton Collaboration were used in only two out of 50 RCTs. The search was limited to RCTs published in English or German and may be missing studies published locally. The reported systematic review suggests room for improvement with respect to the harmonization of safety reporting from developing country vaccine clinical trials and the implementation of standardized case definitions.     

Impact of media reports regarding influenza vaccine on obstetricians’ vaccination practices

BackgroundIn 2017, three media stories regarding influenza vaccine may have impacted obstetricians’ (OB) influenza vaccination practices: reports of reduced influenza vaccine effectiveness, a severe influenza season, and a possible increased risk of miscarriage among pregnant women receiving 2009 H1N1 vaccine in the 1st trimester who had received H1N1 vaccine the previous season (later disproven).ObjectiveDescribe OB’s: (1) awareness of; (2) attitudes and experiences related to; and (3) reported alterations in practice as a result of these reports.MethodsA survey among a nationally representative sample of OBs April to June 2018.ResultsResponse rate was 65% (302/468). 88% of OBs were “very aware” of the severe season, 74% of lower effectiveness, and 25% of the miscarriage study (47% “completely unaware” of miscarriage study). Among those aware, 58%, 57%, and 16% reported ≥10% of pregnant patients initiated discussions about the severe season, lower effectiveness, and miscarriage study, respectively. Most (83%) agreed reports about increased severity increased their enthusiasm for recommending influenza vaccine; fewer agreed reports about the miscarriage study (18%) and lower vaccine effectiveness (12%) decreased their enthusiasm for recommending influenza vaccine. Providers were more likely to initiate discussion with patients about increased severity of the season than the other reports. However, 35% agreed the miscarriage study reports increased their concerns about influenza vaccine safety; 18% (n = 48) reported changing the way they recommended influenza vaccine. Of those, 17 (6% of all respondents) reported not recommending influenza vaccine to women during the 1st trimester and 26 (10% of all respondents) recommended it but were willing to delay until the 2nd trimester.ConclusionsDuring a season in which media stories could have influenced OB influenza vaccination behaviors in different directions, reports underscoring importance of influenza vaccine may have had more impact on OBs’ recommendations than reports questioning vaccine safety or effectiveness.     

The reporting sensitivity of the Vaccine Adverse Event Reporting System (VAERS) for anaphylaxis and for Guillain-Barré syndrome

BackgroundUnderreporting is a limitation common to passive surveillance systems, including the Vaccine Adverse Event Reporting System (VAERS) that monitors the safety of U.S.-licensed vaccines. Nonetheless, previous reports demonstrate substantial case capture for clinically severe adverse events (AEs), including 47% of intussusception cases after rotavirus vaccine, and 68% of vaccine associated paralytic polio after oral polio vaccine.ObjectivesTo determine the sensitivity of VAERS in capturing AE reports of anaphylaxis and Guillain-Barré syndrome (GBS) following vaccination and whether this is consistent with previous estimates for other severe AEs.MethodsWe estimated VAERS reporting rates following vaccination for anaphylaxis and GBS. We used data from VAERS safety reviews as the numerator, and estimated incidence rates of anaphylaxis and GBS following vaccination from the Vaccine Safety Datalink (VSD) studies as the denominator. We defined reporting sensitivity as the VAERS reporting rate divided by the VSD incidence rate. Sensitivity was reported as either a single value, or a range if data were available from >1 study.ResultsVAERS sensitivity for capturing anaphylaxis after seven different vaccines ranged from 13 to 76%; sensitivity for capturing GBS after three different vaccines ranged from 12 to 64%. For anaphylaxis, VAERS captured 13–27% of cases after the pneumococcal polysaccharide vaccine, 13% of cases after influenza vaccine, 21% of cases after varicella vaccine, 24% of cases after both the live attenuated zoster and quadrivalent human papillomavirus (4vHPV) vaccines, 25% of cases after the combined measles, mumps and rubella (MMR) vaccine, and 76% of cases after the 2009 H1N1 inactivated pandemic influenza vaccine. For GBS, VAERS captured 12% of cases after the 2012–13 inactivated seasonal influenza vaccine, 15–55% of cases after the 2009 H1N1 inactivated pandemic influenza vaccine, and 64% of cases after 4vHPV vaccine.ConclusionsFor anaphylaxis and GBS, VAERS sensitivity is comparable to previous estimates for detecting important AEs following vaccination.     

Performance of the Brighton collaboration case definition for hypotonic-hyporesponsive episode (HHE) on reported collapse reactions following infant vaccinations in the Netherlands

We reviewed collapse (sudden onset of pallor, limpness and hyporesponsiveness) following the first infant (DPTP+Hib) vaccination reported to the enhanced passive surveillance system of the Netherlands in 1994-2003. All 1303 reports identified by the current RIVM (National Institute for Public Health and Environment) case definition were captured by the Brighton Collaboration (BC) case definition, with in 17 (1.3%) reports insufficient information. Over the years the proportion of the highest level of diagnostic certainty (level 1) increased due to more complete data from 70% to over 90%. We checked the BC case definition also on a sample of cases (with pallor or hyporesponsiveness) not meeting RIVM's case definition for collapse at the time. Sixty out of 200 cases were captured by BC but again rejected by RIVM. The sensitivity BC levels 2 and 3 appeared too high. We recommend a more restrict case definition by the Brighton Collaboration with certain exclusion criteria to make it more specific. Furthermore a change in the specifications for levels 2 and 3 will increase specificity and accommodate for the loss of sensitivity.     

Surveillance of adverse events after the first trivalent inactivated influenza vaccine produced in mammalian cell culture (Flucelvax®) reported to the Vaccine Adverse Event Reporting System (VAERS), United States, 2013–2015

BackgroundIn November 2012, the first cell cultured influenza vaccine, a trivalent subunit inactivated influenza vaccine (Flucelvax^®, ccIIV3), was approved in the US for adults aged ≥18 years.ObjectiveTo assess adverse events (AEs) after ccIIV3 reported to the US Vaccine Adverse Event Reporting System (VAERS), a spontaneous reporting surveillance system.MethodsWe searched VAERS for US reports after ccIIV3 among persons vaccinated from July 1, 2013–March 31, 2015. Medical records were requested for reports classified as serious (death, hospitalization, prolonged hospitalization, disability, life-threatening-illness), and those suggesting anaphylaxis and Guillain–Barré syndrome (GBS). Physicians reviewed available information and assigned a primary clinical category using MedDRA system organ classes (SOC) to each report. Empirical Bayesian data mining was used to identify disproportional AE reporting following ccIIV3.ResultsVAERS received 629 reports following ccIIV3 of which 313 were for administration of vaccine to persons <18 years. Among 309 reports with an AE documented, 19 (6.1%) were serious and the most common categories were 152 (49.2%) general disorders and administration site conditions (mostly injection site and systemic reactions) and 73 (23.6%) immune system disorders with two reports of anaphylaxis. Four reports of GBS were submitted. Disproportional reporting was identified for ‘drug administered to patient of inappropriate age.’ConclusionsReview of VAERS reports did not identify any concerning pattern of AEs after ccIIV3. Injection site and systemic reactions were the most commonly reported AEs, similar to the pre-licensure clinical trials. Reports following ccIIV3 in persons <18 years highlight the need for education of healthcare providers regarding approved ccIIV3 use.     

Immunization in pregnancy safety surveillance in low and middle-income countries- field performance and validation of novel case definitions

BackgroundA globally standardized approach in high and low and middle-income countries (LMIC) to actively monitor the safety of vaccines for pregnant women during development and implementation phases is critical. Brighton Collaboration’s (BC) Global Alignment of Immunization Safety Assessment in Pregnancy (GAIA) project has developed globally standardized case definitions (CDs) of key obstetric and neonatal terms for the assessment of safety of vaccines in pregnancy. CDs are categorized into levels of diagnostic certainty, facilitating their use in varied settings. This study evaluates the field performance of CDs in LMIC.MethodsData from pregnant participants of RCTs for trivalent inactivated influenza vaccine conducted at Chris Hani Baragwanath Academic Hospital, South Africa (SA) between 2011 and 2013 were reviewed retrospectively for preterm birth, stillbirth and hypertension CDs and the Gestational age assessment (GA) algorithm. Data from an ongoing pneumococcal vaccine trial (conducted at MRC Unit, The Gambia) were collected prospectively for GA.ResultsFor GA, 600 mother-infant dyads from Gambia and 155 mother-infant dyads from SA were reviewed. Level 2B (unsure LMP and US in 2nd trimester) was the most common level seen in Gambia (63%) and level 3B1 (unsure LMP with physical examination) in SA (43%). Preterm deliveries had similar results in SA. The pregnancy-induced hypertension definition performed well, with 96% (54/56) of cases fulfilling ‘level 1’ for ‘preeclampsia with severe features’. 24 stillbirths were identified and 21 records were reviewed; 73.3% (11/15) of the stillbirths classified as antepartum by attending physicians and 83.3% (5/6) of the intrapartum stillbirths did not fulfil the criteria for any level of certainty.ConclusionBC CDs for neonatal and maternal outcomes (preterm and hypertension) and GA were sensitive, reliable and feasible to use in RCTs in SA and Gambia. Modifications to the stillbirth CD are required to improve its usefulness in varied settings.