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

Age- and sex-stratified risks of myocarditis and pericarditis attributable to COVID-19 vaccination: a systematic review and meta-analysis

Although COVID-19 vaccines are generally very safe, the risks of myocarditis and pericarditis after receiving an messenger RNA (mRNA) vaccine have been established, with the highest risk in young men. Most systematic reviews and meta-analyses of the risk of myocarditis or pericarditis have included passive surveillance data, which is subject to reporting errors. Accurate measures of age-, sex-, and vaccine dose- and type-specific risks are crucial for assessment of the benefits and risks of the vaccination. A systematic review and meta-analysis of the risks of myocarditis and pericarditis attributable COVID-19 vaccines were conducted, stratified by age groups, sex, vaccine type, and vaccine dose. Five electronic databases and gray literature sources were searched on November 21, 2023. Article about studies that compared a COVID-19-vaccinated group with an unvaccinated group or time period (eg, self-controlled) were included. Passive surveillance data were excluded. Meta-analyses were conducted using random-effects models. A total of 4030 records were identified; ultimately, 17 articles were included in this review. Compared with unvaccinated groups or unvaccinated time periods, the highest attributable risk of myocarditis or pericarditis was observed after the second dose in boys aged 12-17 years (10.18 per 100 000 doses [95% CI, 0.50-19.87]) of the BNT162b2 vaccine and in young men aged 18-24 years (attributable risk, 20.02 per 100 000 doses [95% CI, 10.47-29.57]) for the mRNA-1273 vaccine. The stratified results based on active surveillance data provide the most accurate available estimates of the risks of myocarditis and pericarditis attributable to specific COVID-19 vaccinations for specific populations. Trial registration: International Prospective Register of Systematic Reviews (PROSPERO) Identifier: CRD42023443343.

[Experiences and Challenges of the Ecuadorean National Advisory Commission on Serious Events Supposedly Attributable to Vaccination or Immunization, 2020-2023Experiências e desafios da Comissão Consultiva Nacional sobre Eventos Supostamente Atribuíveis à Vacinação ou Imunização graves do Equador, 2020-2023]

Objective

To describe the experiences of the National Advisory Commission on Serious Events Supposedly Attributable to Vaccination or Immunization (ESAVI) implemented in Ecuador for the period 2020-2023.

Methods

A report analyzing the implementation, operations, and results of the National Advisory Commission on Serious ESAVI in Ecuador was prepared. A quantitative analysis of vaccination records was carried out, as well as a qualitative analysis based on expert interviews, reflecting the direct experiences and operational challenges faced by the members of the Commission.

Results

Implementation of the Commission has allowed for the systematic recording and analysis of serious ESAVIs. Of 256 reported cases, 139 were analyzed: 59% were considered coincident events; 16.6%, unclassifiable; 6.5%, indeterminate; 5%, stress-related; 3.6% as events related to a programmatic error; and 9.4% as vaccine-related, which included allergic reactions, Guillain-Barré syndrome, and thrombosis, among others. The experts highlighted the need to improve staff training and technology infrastructure, and noted that the Commission played a crucial role in monitoring vaccine safety, as well as in increasing public confidence in vaccination processes.

Conclusions

The National Advisory Commission has played an essential role in vaccine safety surveillance in Ecuador by ensuring reporting, causality analysis, and investigation of serious ESAVIs. Challenges were identified and will need to be addressed to maintain public trust in immunization programs.

Pharmaceutical product recall and educated hesitancy towards new drugs and novel vaccines

Background: Of many pharmaceutical products launched for the benefit of humanity, a significant number have had to be recalled from the marketplace due to adverse events. A systematic review found market recalls for 462 pharmaceutical products between 1953 and 2013. In our current and remarkable period of medical history, excess mortality figures are high in many countries. Yet these statistics receive limited attention, often ignored or dismissed by mainstream news outlets. This excess mortality may include adverse effects caused by novel pharmaceutical agents that use gene-code technology.Objective: To examine key pharmaceutical product withdrawals and derive lessons that inform the current use of gene-based COVID-19 vaccines.Methods: Selective narrative review of historical pharmaceutical recalls and comparative issues with recent COVID-19 vaccines.Results: Parallels with past drug withdrawals and gene-based vaccines include distortion of clinical trial data, with critical adverse event data absent from high-impact journal publications. Delayed regulatory action on pharmacovigilance data to trigger market withdrawal occurred with Vioxx (rofecoxib) and is apparent with the gene-based COVID-19 vaccines.Conclusion: Public health requires access to raw clinical trial data, improved transparency from corporations and heightened, active pharmacovigilance worldwide.

Global burden of vaccine-associated Guillain-Barré syndrome over 170 countries from 1967 to 2023

Research on Guillain-Barré syndrome (GBS) as a neurological adverse effect of vaccines on a global scale is scarce, highlighting the need for further investigation to evaluate its long-term impact and associated risk factors comprehensively. Hence, this study aims to assess the global burden of vaccine-associated GBS and its associated vaccines. This study utilized data from VigiBase, the World Health Organization global database of adverse event reports of medicines and vaccines, encompassing the period from 1967 to 2023 (total reports, n = 131,255,418) to investigate vaccine-associated GBS. Reported odds ratios (ROR) and information components (IC) were analyzed to assess the association between 19 vaccines and the occurrence of vaccine-associated GBS over 170 countries. We identified 15,377 (8072 males [52.49%]) reports of vaccine-associated GBS among 22,616 reports of all drugs-cause GBS from 1978 to 2023. Cumulative reports of vaccine-associated GBS have been increasing steadily over time, with a notable surge observed since the commencement of COVID-19 vaccines administration in 2020. Most vaccines showed significant associations with GBS such as Ad5-vectored COVID-19 vaccines (ROR, 14.88; IC, 3.66), COVID-19 mRNA vaccines (ROR, 9.66; IC, 2.84), and inactivated whole-virus COVID-19 vaccines (ROR, 3,29; IC 1.69). Influenza vaccines showed the highest association (ROR, 77.91; IC 5.98). Regarding age-and sex-specific risks, the association remained similar regardless of sex, with an increased association observed with advancing age. The mean time to onset was 5.5 days. Amid the COVID-19 pandemic, the reports of GBS surged in response to widespread COVID-19 vaccination. Nonetheless, COVID-19 vaccines exhibited the lowest association compared to other vaccines. Vigilance for at least one-week post-vaccination is crucial, particularly for older adults. Further research is warranted to elucidate the underlying mechanisms linking vaccines and GBS.

Incidence of anaphylaxis to YF-VAX® yellow fever vaccination: a retrospective evaluation of vaccine adverse event reports 1999-2018

BACKGROUND

The incidence of anaphylaxis after receipt of yellow fever (YF) vaccine is highly variable based upon previously published reports. Anaphylaxis after receiving the YF vaccine has been reported to range from 0 up to 22 per 1 000 000 doses. Our clinical experience suggested increased incidence, which prompted our investigation. We sought to evaluate the current incidence rate of anaphylaxis after receipt of the 17D-204 strain YF-VAX® brand reported in the US.

METHODS

We performed a retrospective review of the Vaccine Adverse Event Reporting System (VAERS) reports of anaphylaxis after receiving the YF-VAX vaccine occurring between 1 October 1999 and 30 September 2018. We utilized the Brighton Collaboration Case Definition and inclusion determination was made by a board-certified allergist. We also obtained the total number of YF-VAX doses distributed across the US during this same time-period and then calculated an updated incidence rate of YF-VAX vaccine-associated anaphylaxis.

RESULTS

We identified 132 potential cases of possible or probable anaphylaxis. Of these, 111 met inclusion criteria: level 1 (n = 51), level 2 (n = 59) and level 3 (n = 1). The manufacturer reported a total distribution of 7 624 160 doses of YF-VAX from 1 October 1999 to 30 September 2018. The calculated incidence rate of YF-VAX vaccine-associated anaphylaxis is estimated at 14.6 events per 1 000 000 doses.

CONCLUSIONS

We conclude the estimated rate of anaphylaxis per VAERS reports is 14.6 events per 1 000 000 doses after YF-VAX vaccination. This is consistent with some previous reports and substantially higher than rates of anaphylaxis after other vaccines.

Determinants of COVID-19 vaccine-induced myocarditis

BACKGROUND

Following the roll-out of the Pfizer-BioNTech BNT162b2, Moderna mRNA-1273, and Janssen Ad26.COV2.S coronavirus disease 2019 (COVID-19) injections in the United States, millions of individuals have reported adverse events (AEs) using the vaccine adverse events reports system (VAERS). The objective of this analysis is to describe the myocarditis data in VAERS and the COVID-19 vaccines as potential determinants of myocarditis.

METHODS

We used VAERS data to examine the frequency of reporting myocarditis since the beginning of the mass vaccination campaign and compared this with historical values in VAERS and COVID-19 vaccine administration data from the Our World in Data database. We examined myocarditis reports in VAERS in the context of sex, age, and dose. Statistical analysis was done using the Student's t-test to determine statistically significant differences between ages among myocarditis adverse events (AEs) and the chi-square test to determine relationships between categorical variables with statistical significance.

RESULTS

We found the number of myocarditis reports in VAERS after COVID-19 vaccination in 2021 was 223 times higher than the average of all vaccines combined for the past 30 years. This represented a 2500% increase in the absolute number of reports in the first year of the campaign when comparing historical values prior to 2021. Demographic data revealed that myocarditis occurred most in youths (50%) and males (69%). A total of 76% of cases resulted in emergency care and hospitalization. Of the total myocarditis reports, 92 individuals died (3%). Myocarditis was more likely after dose 2 (p < 0.00001) and individuals less than 30 years of age were more likely than individuals older than 30 to acquire myocarditis (p < 0.00001).

CONCLUSION

COVID-19 vaccination is strongly associated with a serious adverse safety signal of myocarditis, particularly in children and young adults resulting in hospitalization and death. Further investigation into the underlying mechanisms of COVID-19 vaccine-induced myocarditis is imperative to create effective mitigation strategies and ensure the safety of COVID-19 vaccination programs across populations.

Gene-based COVID-19 vaccines: Australian perspectives in a corporate and global context

Pandemic management requires societal coordination, global orchestration, respect for human rights and defence of ethical principles. Yet some approaches to the COVID-19 pandemic, driven by socioeconomic, corporate, and political interests, have undermined key pillars of ethical medical science. We explore significant mistakes that may have occurred in recent pandemic control, in order to better navigate the future. Within corporate and geopolitical infrastructure, we review the COVID-19 pandemic and novel mRNA and viral-vector DNA COVID-19 vaccines, deployed by wealthy western countries. The pandemic, together with rollouts of unconventional, gene-based vaccine technology, has provided experimental opportunity to engineer social control of entire populations. The haste and scale of development, production, and distribution of these new pharmaceuticals is unprecedented in history. Key phase III clinical trials for these products are yet to be fully completed, despite administration to billions of people. Mass vaccination of workforces has been mandated, and vaccine mandates correlate with excess mortality. Many independent data sets concur - we have experienced a pandemic of viral illness, followed by a pandemic of vaccine injury. For Australia, matters have operated the other way around. Vaccination followed later by the main viral wave. Australian excess mortality data correlates with this. Neither risk nor cost can justify these products for the vast majority of people. Lack of efficacy against infection and transmission, and the equivalent benefits of natural immunity, obviate mandatory therapeutics. With the many gene-based pharmaceuticals planned, a new era of pathology lies ahead. We should pause, reflect, and reaffirm essential freedoms, welcome the end of the COVID-19 pandemic, embrace natural immunity, and lift all mandated medical therapy.

Feline Injection-Site Sarcoma and Other Adverse Reactions to Vaccination in Cats

Vaccine-associated adverse events (VAAEs), including feline injection-site sarcomas (FISSs), occur only rarely but can be severe. Understanding potential VAAEs is an important part of informed owner consent for vaccination. In this review, the European Advisory Board on Cat Diseases (ABCD), a scientifically independent board of feline medicine experts, presents the current knowledge on VAAEs in cats, summarizing the literature and filling the gaps where scientific studies are missing with expert opinion to assist veterinarians in adopting the best vaccination practice. VAAEs are caused by an aberrant innate or adaptive immune reaction, excessive local reactions at the inoculation site, an error in administration, or failure in the manufacturing process. FISS, the most severe VAAE, can develop after vaccinations or injection of other substances. Although the most widely accepted hypothesis is that chronic inflammation triggers malignant transformation, the pathogenesis of FISS is not yet fully understood. No injectable vaccine is risk-free, and therefore, vaccination should be performed as often as necessary, but as infrequently as possible. Vaccines should be brought to room temperature prior to administration and injected at sites in which FISS surgery would likely be curative; the interscapular region should be avoided. Post-vaccinal monitoring is essential.

Reporting rates for VAERS death reports following COVID-19 vaccination, December 14, 2020-November 17, 2021

PURPOSE

Despite widely available safety information for the COVID-19 vaccines, vaccine hesitancy remains a challenge. In some cases, vaccine hesitancy may be related to concerns about the number of reports of death to the Vaccine Adverse Event Reporting System (VAERS). We aimed to provide information and context about reports of death to VAERS following COVID-19 vaccination.

METHODS

This is a descriptive study evaluating reporting rates for VAERS death reports for COVID-19 vaccine recipients in the United States between December 14, 2020, and November 17, 2021. Reporting rates were calculated as death events per million persons vaccinated and compared to expected all-cause (background) death rates.

RESULTS

9201 death events were reported for COVID-19 vaccine recipients aged 5 years and older (or age unknown). Reporting rates for death events increased with increasing age, and males generally had higher reporting rates than females. For death events within 7 days and 42 days of vaccination, respectively, observed reporting rates were lower than the expected all-cause death rates. Reporting rates for Ad26.COV2.S vaccine were generally higher than for mRNA COVID-19 vaccines, but still lower than the expected all-cause death rates. Limitations of VAERS data include potential reporting bias, missing or inaccurate information, lack of a control group, and reported diagnoses, including deaths, are not causally verified diagnoses.

CONCLUSIONS

Reporting rates for death events were lower than the all-cause death rates expected in the general population. Trends in reporting rates reflected known trends in background death rates. These findings do not suggest an association between vaccination and overall increased mortality.

A practical guide to address reactions to vaccines in children

Currently available vaccines are safe, but, potentially, any vaccine can cause an allergic reaction and, albeit very rare, anaphylaxis can occur. Although its rarity, the precise diagnostic management of a suspected anaphylaxis postvaccination is of paramount importance due to the risk of a potentially serious reaction after re-exposure, while a misdiagnosis might lead to an increase in the number of children that interrupt vaccinations resulting in an unjustifiably individual and collective risk of loss of protection against immune preventable diseases. In the light that most cases of suspected allergy to a vaccine are not effectively confirmed in up to 85% of the cases referred for an allergy evaluation, patients can continue the vaccination schedule with the same formulation and tolerance of the booster doses. The patient assessment has to be done by an expert in the vaccine field, usually an allergist or an immunologist depending on the country, to select subjects at risk of allergic reactions and to perform the correct procedures for vaccine hypersensitivity diagnosis and management, in order to guarantee safe immunization practices. The aim of this review is to provide a practical guidance for the safe management of allergic children undergoing immunization procedures. The guide is referred both to the evaluation of children who have previously experienced a suspected allergic reaction to a specific vaccine and their management in case of further booster doses, and to children allergic to a component of the vaccine to be administered.

Anaphylactic Reactions to COVID-19 Vaccines: An Updated Assessment Based on Pharmacovigilance Data

This study aimed at producing an updated assessment of the incidence of anaphylaxis associated with COVID-19 vaccines based on pharmacovigilance data. Anaphylactic reaction and anaphylactic shock data post-COVID-19-vaccination reported from week 52, 2020 to week 1 or week 2, 2023 were collected from the VAERS and EudraVigilance databases, respectively, and analyzed comparatively. Incidence rates were calculated using the corresponding administered vaccine doses as denominators for all licensed vaccines and both platform types (mRNA or vectored). The latest data from the present analysis showed lower anaphylaxis incidence associated with COVID-19 vaccination compared to previous estimates from week 52, 2020 to week 39, 2021 (anaphylactic reaction: 8.96 (95% CI 8.80-9.11)/million doses overall (EEA: 14.19 (95% CI 13.92-14.47)/million/US: 3.17 (95% CI 3.03-3.31)/million); anaphylactic shock: 1.46 (95% CI 1.39-1.52)/million doses overall (EEA: 2.47 (95% CI 2.36-2.58)/million/US: 0.33 (95% CI 0.29-0.38)/million)). Incidence rates varied by vaccine and were higher as captured in EudraVigilance compared to the VAERS and for vectored compared to mRNA vaccines. Most reported cases had a favorable outcome. The extremely rare fatalities (overall rates across continents 0.04 (95% CI 0.03-0.06)/million doses for anaphylactic reaction and 0.02 (95% CI 0.01-0.03)/million vaccine doses for anaphylactic shock) were also associated with vector-rather than mRNA-based vaccines. The diminished incidence of anaphylaxis post-vaccination with COVID-19 vaccines offers assurance about their safety, as does the continuous potential adverse events monitoring through specialized pharmacovigilance databases.

Vaccine-Associated Uveitis after COVID-19 Vaccination: Vaccine Adverse Event Reporting System Database Analysis

PURPOSE

To assess the risk of vaccine-associated uveitis (VAU) after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination and evaluate uveitis onset interval and clinical presentations in the patients.

DESIGN

A retrospective study from December 11, 2020, to May 9, 2022, using the Centers for Disease Control and Prevention Vaccine Adverse Event Reporting System.

PARTICIPANTS

Patients diagnosed with VAU after administration of BNT162b2 (Pfizer-BioNTech, Pfizer Inc/BioNTech SE), mRNA-1273 (Moderna, Moderna Therapeutics Inc), and Ad26.COV2.S (Janssen, Janssen Pharmaceuticals) vaccine worldwide.

METHODS

A descriptive analysis of the demographics, clinical history, and presentation was performed. We evaluated the correlation among the 3 vaccines and continuous and categorical variables. A post hoc analysis was performed between uveitis onset interval after vaccination and age, dose, and vaccine type. Finally, a 30-day risk analysis for VAU onset postvaccination was performed.

MAIN OUTCOME MEASURES

The estimated global crude reporting rate, observed to expected ratio of VAU in the United States, associated ocular and systemic presentations, and onset duration.

RESULTS

A total of 1094 cases of VAU were reported from 40 countries with an estimated crude reporting rate (per million doses) of 0.57, 0.44, and 0.35 for BNT162b2, mRNA-1273, and Ad26.COV2.S, respectively. The observed to expected ratio of VAU was comparable for BNT162b2 (0.023), mRNA-1273 (0.025), and Ad26.COV2.S (0.027). Most cases of VAU were reported in patients who received BNT162b2 (n = 853, 77.97%). The mean age of patients with VAU was 46.24 ± 16.93 years, and 68.65% (n = 751) were women. Most cases were reported after the first dose (n = 452, 41.32%) and within the first week (n = 591, 54.02%) of the vaccination. The onset interval for VAU was significantly longer in patients who received mRNA-1273 (21.22 ± 42.74 days) compared with BNT162b2 (11.42 ± 23.16 days) and rAd26.COV2.S (12.69 ± 16.02 days) vaccines (P < 0.0001). The post hoc analysis revealed a significantly shorter interval of onset for the BNT162b2 compared with the mRNA 1273 vaccine (P < 0.0001). The 30-day risk analysis showed a significant difference among the 3 vaccines (P < 0.0001).

CONCLUSIONS

The low crude reporting rate and observed to expected ratio suggest a low safety concern for VAU. This study provides insights into a possible temporal association between reported VAU events and SARS-CoV-2 vaccines; however, further investigations are required to delineate the associated immunological mechanisms.

Death and Disability Reported with Cases of Vaccine Anaphylaxis Stratified by Administration Setting: An Analysis of the Vaccine Adverse Event Reporting System from 2017 to 2022

The serious nature of post-vaccination anaphylaxis requires healthcare professionals to be adequately trained to respond to these hypersensitivity emergencies. The aim of this study was to compare outcomes reported with cases of vaccine anaphylaxis stratified by administration setting. We queried reports in the Vaccine Adverse Event Reporting System (VAERS) database from 2017 to 2022 and identified cases involving anaphylaxis with an onset within one day of vaccine administration. The primary outcome was the combined prevalence of death or disability for each setting while the secondary outcome was the prevalence of hospitalization. Adjusted (age, sex, prior history of allergy, vaccine type) odds ratios (aOR) and associated 95% confidence intervals (CI) were calculated using logistic regression analysis. A total of 2041 cases of anaphylaxis comprised the primary study cohort with representation in the sample from all 50 US states and the District of Columbia. The mean age was 43.3 ± 17.5 years, and most cases involved women (79.9%). Cases of anaphylaxis were reported after receiving a coronavirus vaccine (85.2%), influenza vaccine (5.9%), tetanus vaccine (2.2%), zoster vaccine (1.6%), measles vaccine (0.7%), and other vaccine (4.5%). Outcomes associated with reports of vaccine anaphylaxis included 35 cases of death and disability and 219 hospitalizations. Compared with all other settings, the aOR of death and disability when anaphylaxis occurred was 1.92 (95% CI, 0.86-4.54) in a medical provider's office, 0.85 (95% CI, 0.26-2.43) in a pharmacy and 1.01 (95% CI, 0.15-3.94) in a public health clinic. Compared with all other settings, the aOR of hospitalization when anaphylaxis occurred was 1.02 (95% CI, 0.71-1.47) in a medical provider's office, 1.06 (95% CI, 0.72-1.54) in a pharmacy, and 1.12 (95% CI, 0.61-1.93) in a public health clinic. An analysis of a national database across six years revealed no significant differences in the odds of death/disability and odds of hospitalization associated with post-vaccination anaphylaxis in the medical office, pharmacy, and public health clinic compared with all other settings. This study expands our understanding of the safety of immunization services and reinforces that all settings must be prepared to respond to such an emergency.

Hearing disorder following COVID ‐19 vaccination: A pharmacovigilance analysis using the Vaccine Adverse Event Reporting System

What is known and objective

Evidence on whether the coronavirus disease 2019 (COVID‐19) vaccination could cause hearing‐related adverse events is still conflicting. This study aims to access the association between COVID‐19 vaccine and hearing disorder.

Methods

The Vaccine Adverse Event Reporting System (VAERS) was queried between January 2020 to November 2021. The disproportionality pattern for hearing impairment of COVID‐19 vaccine was accessed by calculating the reporting odds ratio (ROR) and proportional reporting ratio (PRR). A further subgroup analysis based on the type of COVID‐19 vaccine and the doses administered was performed. In addition, the disproportionalities for hearing dysfunction between COVID‐19 and influenza vaccines were compared.

Results and discussion

A total of 14,956 reports of hearing‐related adverse events were identified with COVID‐19 vaccination and 151 with influenza vaccine during the analytic period in VAERS. The incidence of hearing disorder following COVID‐19 vaccination was 6.66 per 100,000. The results of disproportionality analysis revealed that the adverse events of hearing impairment, after administration of COVID‐19 vaccine, was significantly highly reported (ROR 2.38, 95% confidence interval [CI] 2.20–2.56; PRR: 2.35, χ² 537.58), for both mRNA (ROR 2.37, 95% CI 2.20–2.55; PRR 2.34, χ² 529.75) and virus vector vaccines (ROR 2.50, 95% CI 2.28–2.73; PRR 2.56, χ² 418.57). While the disproportional level for hearing dysfunction was quite lower in influenza vaccine (ROR 0.36, 95% CI 0.30–0.42; PRR 0.36, χ² 172.24).

What is new and conclusion

This study identified increased risk for hearing disorder following administration of both mRNA and virus vector COVID‐19 vaccines compared to influenza vaccination in real‐world settings.

Usefulness of Vaccine Adverse Event Reporting System for Machine-Learning Based Vaccine Research: A Case Study for COVID-19 Vaccines

Usefulness of Vaccine-Adverse Event-Reporting System (VAERS) data and protocols required for statistical analyses were pinpointed with a set of recommendations for the application of machine learning modeling or exploratory analyses on VAERS data with a case study of COVID-19 vaccines (Pfizer-BioNTech, Moderna, Janssen). A total of 262,454 duplicate reports (29%) from 905,976 reports were identified, which were merged into a total of 643,522 distinct reports. A customized online survey was also conducted providing 211 reports. A total of 20 highest reported adverse events were first identified. Differences in results after applying various machine learning algorithms (association rule mining, self-organizing maps, hierarchical clustering, bipartite graphs) on VAERS data were noticed. Moderna reports showed injection-site-related AEs of higher frequencies by 15.2%, consistent with the online survey (12% higher reporting rate for pain in the muscle for Moderna compared to Pfizer-BioNTech). AEs {headache, pyrexia, fatigue, chills, pain, dizziness} constituted >50% of the total reports. Chest pain in male children reports was 295% higher than in female children reports. Penicillin and sulfa were of the highest frequencies (22%, and 19%, respectively). Analysis of uncleaned VAERS data demonstrated major differences from the above (7% variations). Spelling/grammatical mistakes in allergies were discovered (e.g., ~14% reports with incorrect spellings for penicillin).

Comparability of clinical trials and spontaneous reporting data regarding COVID-19 vaccine safety

Severe adverse events (AEs) after COVID-19 vaccination are not well studied in randomized controlled trials (RCTs) due to rarity and short follow-up. To monitor the safety of COVID-19 vaccines ("Pfizer" vaccine dose 1 and 2, "Moderna" vaccine dose 1 and 2, and "Janssen" vaccine single dose) in the U.S., especially regarding severe AEs, we compare the relative rankings of these vaccines using both RCT and the Vaccine Adverse Event Reporting System (VAERS) data. The risks of local and systemic AEs were assessed from the three pivotal COVID-19 vaccine trials and also calculated in the VAERS cohort consisting of 559,717 reports between December 14, 2020 and September 17, 2021. AE rankings of the five vaccine groups calculated separately by RCT and VAERS were consistent, especially for systemic AEs. For severe AEs reported in VAERS, the reported risks of thrombosis and GBS after Janssen vaccine were highest. The reported risk of shingles after the first dose of Moderna vaccine was highest, followed by the second dose of the Moderna vaccine. The reported risk of myocarditis was higher after the second dose of Pfizer and Moderna vaccines. The reported risk of anaphylaxis was higher after the first dose of Pfizer vaccine. Limitations of this study are the inherent biases of the spontaneous reporting system data, and only including three pivotal RCTs and no comparison with other active vaccine safety surveillance systems.

BNT162b2 Vaccine-Associated Myo/Pericarditis in Adolescents: A Stratified Risk-Benefit Analysis

BACKGROUND

Male patients ages 12-17 years have an elevated risk of mRNA vaccination-associated myo/pericarditis. A risk-benefit analysis of first and second doses of mRNA vaccination in adolescent boys by health status and history of SARS-CoV-2 infection has not been performed.

METHODS

Using the Vaccine Adverse Event Reporting System (VAERS), we identified BNT162b2 [Pfizer-BioNTech] myo/pericarditis occurrence according to CDC criteria. Main outcomes were as follows: 1) post-vaccination myo/pericarditis crude incidence in adolescents aged 12-15 and 16-17; and 2) two risk-benefit analyses by age, sex, comorbidity, variant and history of infection.

RESULTS

Cases of myo/pericarditis (n = 253) included 129 after dose 1 and 124 after dose 2; 86.9% were hospitalized. Incidence per million after dose two in male patients aged 12-15 and 16-17 was 162.2 and 93.0, respectively. Weighing post-vaccination myo/pericarditis against COVID-19 hospitalization during delta, our risk-benefit analysis suggests that among 12-17-year-olds, two-dose vaccination was uniformly favourable only in nonimmune girls with a comorbidity. In boys with prior infection and no comorbidities, even one dose carried more risk than benefit according to international estimates. In the setting of omicron, one dose may be protective in nonimmune children, but dose two does not appear to confer additional benefit at a population level.

CONCLUSIONS

Our findings strongly support individualized paediatric COVID-19 vaccination strategies which weigh protection against severe disease vs. risks of vaccine-associated myo/pericarditis. Research is needed into the nature and implications of this adverse effect as well as immunization strategies which reduce harms in this overall low-risk cohort.

Guillain-Barre syndrome following COVID-19 vaccines: A scoping review

Guillain-Barre syndrome following COVID-19 vaccines (GBSfCV19v) is a reported adverse effect that remains unclear. We present a structured review based on two case reports of GBSfCV19v, a systematic review, and Vaccine Adverse Event Reporting System (VAERS) analysis to estimate the risk and describe the clinical characteristics (CC) of these events. We've searched on MEDLINE and Embase, from the inception to May 20, 2021, using the keywords: "Guillain barre syndrome" and cross-referenced with "covid-19 vaccines." We estimated the risk of GBSfCV19v, comparing it with the risk of GBS following the influenza vaccine (GBSfIv), considering the VAERS sensitivity. The clinical characteristics included: age, sex, comorbidities, type of vaccine, administered dose, clinical onset, deaths, cerebrospinal fluid (CSF), and electromyography (EMG) pattern. We found 43 cases, considering the risk of GBSfCV19v lower than GBSfIv (160-320 cases). The patients had a mean age of 54 years and 23 (56%) were male. The types of vaccines used: Pfizer (22), Moderna (9), AstraZeneca (3), Janssen (3), and Johnson & Johnson (1). 24 cases of GBS occurred after the first dose, with clinical onset of 7 days. CSF albuminocytological dissociation was reported in 7 patients, and EMG revealed a predominant demyelinating pattern. GBSfCV19v risk appears to be lower than what was expected from other respiratory virus vaccines. Most cases of GBS were middle-aged males within a week following the first dose of the COVID-19 vaccine, showing a typical demyelinating neuropathy with albuminocytological dissociation.

Assessment of Sudden Sensorineural Hearing Loss After COVID-19 Vaccination

IMPORTANCE

Emerging reports of sudden sensorineural hearing loss (SSNHL) after COVID-19 vaccination within the otolaryngological community and the public have raised concern about a possible association between COVID-19 vaccination and the development of SSNHL.

OBJECTIVE

To examine the potential association between COVID-19 vaccination and SSNHL.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study and case series involved an up-to-date population-based analysis of 555 incident reports of probable SSNHL in the Centers for Disease Control and Prevention Vaccine Adverse Events Reporting System (VAERS) over the first 7 months of the US vaccination campaign (December 14, 2020, through July 16, 2021). In addition, data from a multi-institutional retrospective case series of 21 patients who developed SSNHL after COVID-19 vaccination were analyzed. The study included all adults experiencing SSNHL within 3 weeks of COVID-19 vaccination who submitted reports to VAERS and consecutive adult patients presenting to 2 tertiary care centers and 1 community practice in the US who were diagnosed with SSNHL within 3 weeks of COVID-19 vaccination.

EXPOSURES

Receipt of a COVID-19 vaccine produced by any of the 3 vaccine manufacturers (Pfizer-BioNTech, Moderna, or Janssen/Johnson & Johnson) used in the US.

MAIN OUTCOMES AND MEASURES

Incidence of reports of SSNHL after COVID-19 vaccination recorded in VAERS and clinical characteristics of adult patients presenting with SSNHL after COVID-19 vaccination.

RESULTS

A total of 555 incident reports in VAERS (mean patient age, 54 years [range, 15-93 years]; 305 women [55.0%]; data on race and ethnicity not available in VAERS) met the definition of probable SSNHL (mean time to onset, 6 days [range, 0-21 days]) over the period investigated, representing an annualized incidence estimate of 0.6 to 28.0 cases of SSNHL per 100 000 people per year. The rate of incident reports of SSNHL was similar across all 3 vaccine manufacturers (0.16 cases per 100 000 doses for both Pfizer-BioNTech and Moderna vaccines, and 0.22 cases per 100 000 doses for Janssen/Johnson & Johnson vaccine). The case series included 21 patients (mean age, 61 years [range, 23-92 years]; 13 women [61.9%]) with SSNHL, with a mean time to onset of 6 days (range, 0-15 days). Patients were heterogeneous with respect to clinical and demographic characteristics. Preexisting autoimmune disease was present in 6 patients (28.6%). Of the 14 patients with posttreatment audiometric data, 8 (57.1%) experienced improvement after receiving treatment. One patient experienced SSNHL 14 days after receiving each dose of the Pfizer-BioNTech vaccine.

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, findings from an updated analysis of VAERS data and a case series of patients who experienced SSNHL after COVID-19 vaccination did not suggest an association between COVID-19 vaccination and an increased incidence of hearing loss compared with the expected incidence in the general population.

Vaccination in pediatric acquired inflammatory immune-mediated neuromuscular disorders

AIM

To analyse literature data on vaccine related induction, worsening of the disease and disease reccurrences as well as vaccine safety and efficacy among pediatric patients with acquired inflammatory immune-mediated neuromuscular disorders (NMD).

METHODS

Medline, Pub Med and Scopus database search from 1975 to 2020 focused on pediatric age was conducted including peer reviews, meta analyses and epidemiological studies on vaccination and Guillain-Barré syndrome (GBS), Bell's palsy, optic neuritis (ON), myasthenia gravis (MG), chronic inflammatory demyelinating polyneuropathy (CIDP) and immune-mediated inflammatory myopathy (IM).

RESULTS AND CONCLUSION

s: There are no strong evidence supporting relationship between vaccination with different pediatric vaccines and development of first episodes or reccurrences of GBS, Bell's palsy, optic neuritis (ON), juvenile MG, CIDP, and IM. The vaccination and revaccination with inactivated vaccines is considered safe in children with medical history of GBS, Bell's palsy, ON, MG and IM. Caution when immunization against influenza, quadrivalent conjugated meningococcal vaccine (MCV4) and pneumococcal disease and avoiding tetanus toxoid immunization in CIDP patients is suggested. Patients with immune mediated acquired NMD should be vaccinated with live vaccines before the initiation of immunosupressive treatment. Immunosuppressed patients with low protective antibody titers should be considered for revaccination.

Anaphylaxis rates associated with COVID-19 vaccines are comparable to those of other vaccines

We retrieved data on 8940 anaphylaxis cases post-COVID-19 vaccination from the US Vaccine Adverse Event Reporting System and the European EudraVigilance from week 52/2020 through week 31/2021 and compared them with those of other vaccines. Overall, 837,830,000 COVID-19 vaccine doses were delivered in the US and Europe during the study period, for which the vaccine name was known. The mean anaphylaxis rate was estimated at 10.67 cases per 10⁶ doses of COVID-19 vaccines (range: 7.99-19.39 cases per 10⁶ doses depending on the vaccine). COVID-19 vaccines ranked fifth in reported anaphylaxis rates, behind rabies, tick-borne encephalitis, measles-mumps-rubella-varicella, and human papillomavirus vaccines (70.77, 20, 19.8, and 13.65 cases per 10⁶ vaccine doses, respectively). COVID-19 vaccines are within the range of anaphylaxis rates reported across several common vaccines in these two passive reporting systems. These data should be communicated to reassure the general population about the safety profile of COVID-19 vaccines.

Immunization practices and risk of anaphylaxis: a current update, comprehensive of COVID-19 vaccination data

PURPOSE OF REVIEW

This review aims to provide an updated report in regards to the correlation between vaccines and anaphylaxis and the related risk in the population.

RECENT FINDINGS

Initial reports showed higher incidence of anaphylaxis following messenger RNA COVID-19 vaccines compared with 'routine' vaccinations, likely influenced by the great attention paid to these 'new' vaccines. However, anaphylaxis has still to be considered quite rare and its incidence will be systematically reconsidered in the light of additional data collected.

SUMMARY

Adverse reactions to vaccines are commonly reported but most of them are nonspecific mild events, whereas vaccine-related anaphylaxis is considered a rare event, with an incidence rate equal to 1.3 cases per million vaccine doses administered. As anaphylaxis reports usually start to be reported to passive pharmacovigilance during postmarketing surveillance, the first data are used to be influenced by under- and over-reporting and lack of denominators and following studies are needed to confirm the causal relationship. This might create an initial overcautiously approach to new immunization practices but, being anaphylaxis a potential life-threatening event, every suspected contraindication has to be deepened to maximize effectiveness and safety profile and constantly redefined not to exclude an overestimated population group who could receive the vaccine uneventfully.

Safety Surveillance of Bivalent Meningococcal Group B Vaccine, Vaccine Adverse Event Reporting System, 2014-2018

BACKGROUND

In October 2014, MenB-FHbp (Trumenba, Pfizer) became the first meningococcal group B vaccine licensed in the United States. It is approved for use in individuals aged 10-25 years. Our objective was to evaluate the safety of MenB-FHbp postlicensure.

METHODS

The Vaccine Adverse Event Reporting System (VAERS) is a national passive vaccine safety surveillance system. We analyzed US VAERS reports for MenB-FHbp received from the date of licensure in October 2014 through December 2018. We described the characteristics of the persons and adverse events (AEs) reported and calculated reporting rates using the number of doses distributed. We used empirical Bayesian data mining to identify AEs reported at least twice as often as expected compared with all other vaccines.

RESULTS

VAERS received 2106 reports involving MenB-FHbp, representing 698 reports per million doses distributed. The median age of vaccinees was 17 years, and 55% were female. MenB-FHbp was given simultaneously with other vaccines in 37% of reports. Most reports (57%) described AEs that started on the day of or day after vaccination. The most common AEs reported were pyrexia (27%), headache (25%), and pain (16%). There were 44 serious reports (2% of all reports), among which 42 reported a hospitalization. Data mining identified disproportional reporting of headache, pyrexia, chills, and myalgia.

CONCLUSIONS

The AEs most commonly or disproportionately reported following MenB-FHbp were consistent with those identified in clinical trials as described in the US package insert. We did not identify any new safety issues.