Anaphylaxis rates following mRNA COVID-19 vaccination in children and adolescents: analysis of data reported to EudraVigilance

Aim The present study aimed to estimate the anaphylaxis rates following mRNA COVID-19 vaccination in children and adolescents in Europe. Methods We retrieved data on 371 anaphylaxis cases following mRNA COVID-19 vaccination in children ≤ 17 years old notified to EudraVigilance as of October 8, 2022. Overall, 27,120,512 doses of BNT162b2 vaccine and 1,400,300 doses of mRNA-1273 vaccine have been delivered to children during the study period. Results The overall mean anaphylaxis rate was 12.81 [95% confidence interval (CI): 11.49-14.12] per 106 mRNA vaccine doses [12.14 (95% CI: 6.37-17.91) per 106 doses for mRNA-1273 and 12.84 (95% CI: 11.49-14.19) per 106 doses for BNT162b2]. Children 12-17 years old accounted for 317 anaphylaxis cases, followed by 48 cases in children 3-11 years old, and 6 cases in children 0-2 years old. Children 10-17 years old had a mean anaphylaxis rate of 13.52 (95% CI: 12.03-15.00) cases per 106 mRNA vaccine doses and children 5-9 years old had a mean anaphylaxis rate of 9.51 (95% CI: 6.82-12.20) cases per 106 mRNA vaccine doses. There were two fatalities, both in the 12-17 years age group. The fatal anaphylaxis rate was 0.07 cases per 106 mRNA vaccine doses. Conclusions Anaphylaxis is a rare adverse event after receiving an mRNA COVID-19 vaccine in children. Continuous surveillance of serious adverse events is needed to guide vaccination policies as we move towards SARS-CoV-2 endemicity. Larger real-world studies on COVID-19 vaccination in children, using clinical case confirmation, are imperative.

Anaphylaxis rates following mRNA COVID-19 vaccination in children and adolescents: Analysis of data reported to EudraVigilance.

AIM: The present study aimed to estimate the anaphylaxis rates following mRNA COVID-19 vaccination in children and adolescents in Europe. METHODS: We retrieved data on 371 anaphylaxis cases following mRNA COVID-19 vaccination in children ≤ 17 years old notified to EudraVigilance as of October 8, 2022. Overall, 27,120,512 doses of BNT162b2 vaccine and 1,400,300 doses of mRNA-1273 vaccine have been delivered to children during the study period. RESULTS: The overall mean anaphylaxis rate was 12.81 [95% confidence interval (CI): 11.49-14.12] per 106 mRNA vaccine doses [12.14 (95% CI: 6.37-17.91) per 106 doses for mRNA-1273 and 12.84 (95% CI: 11.49-14.19) per 106 doses for BNT162b2]. Children 12-17 years old accounted for 317 anaphylaxis cases, followed by 48 cases in children 3-11 years old, and 6 cases in children 0-2 years old. Children 10-17 years old had a mean anaphylaxis rate of 13.52 (95% CI: 12.03-15.00) cases per 106 mRNA vaccine doses and children 5-9 years old had a mean anaphylaxis rate of 9.51 (95% CI: 6.82-12.20) cases per 106 mRNA vaccine doses. There were two fatalities, both in the 12-17 years age group. The fatal anaphylaxis rate was 0.07 cases per 106 mRNA vaccine doses. CONCLUSIONS: Anaphylaxis is a rare adverse event after receiving an mRNA COVID-19 vaccine in children. Continuous surveillance of serious adverse events is needed to guide vaccination policies as we move towards SARS-CoV-2 endemicity. Larger real-world studies on COVID-19 vaccination in children, using clinical case confirmation, are imperative.

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.

Comparative assessment of myocarditis and pericarditis reporting rates related to mRNA COVID-19 vaccines in Europe and the United States.

OBJECTIVES: The novel mRNA vaccines proved to be safe and effective in averting severe COVID-19. Vaccine-related complications recorded by pharmacovigilance systems, such as 'EudraVigilance' in Europe and 'VAERS' in the United States (US), rarely include myocarditis and pericarditis. Given the novelty of the platform and the increasing global-scale vaccine production needs, we assessed their reporting rates comparatively across continents. METHODS: Data of myocarditis and pericarditis cases post COVID-19 vaccination reported from week 52/2020 (December 21 to 27, 2020) to week 40/2021 (October 4 to 10, 2021) were collected for mRNA vaccines from EudraVigilance and VAERS. The corresponding administered vaccine doses were used as denominators to estimate reporting rates for comparison purposes. Cross-tabulation analysis was employed to compare the reporting rates of mRNA vaccines-associated myocarditis and pericarditis between EudraVigilance and VAERS. RESULTS: Low reporting rates of myocarditis (7.64/million vaccine doses) and pericarditis (5.32/million) were found, with higher rates of both disorders in EudraVigilance compared to VAERS; these differences were more pronounced post-mRNA-1273 (5-6-fold, p=0.000 for myocarditis and p<0.001 for pericarditis) than post-BNT162b2 vaccination (1.5-2-fold, p<0.001 for both conditions). Most myocarditis cases occurred in males <30 years. Pericarditis affected predominantly males <40 and both sexes >40 years. The extremely rare fatalities related to myocarditis (0.102/million) or pericarditis (0.017/million) were also higher in EudraVigilance versus VAERS. CONCLUSIONS: Understanding the underlying causes of the observed differences could provide guidance for the enhanced quality of mRNA vaccines that would also foster vaccine acceptance.

Temporal relationship of myocarditis and pericarditis following COVID-19 vaccination: A pragmatic approach.

BACKGROUND: Complications following COVID-19 vaccination, particularly with mRNA vaccines, rarely include myocarditis and pericarditis. This work principally aimed at defining a realistic temporal relationship between vaccination and myocarditis/pericarditis development. METHODS: All relevant cases reported from week 52/2020 through week 41/2021 in the VAERS database were retrieved and analyzed for licensed vaccines. These included BNT162b2, mRNA-1273, and AD26.COV2·S. Incidence rates were calculated using the corresponding administered vaccine doses as denominators. Additionally, analyzed parameters included demographics, dose series, hospitalization length and outcome. RESULTS: Overall, 2016 myocarditis and 1380 pericarditis cases, (4.96/106 and 3.40/106 administered vaccine doses, respectively), were recorded. Most myocarditis cases occurred following BNT162b2 (5.60/106 doses) in males <30 years. Pericarditis affected predominantly males <40, both sexes >40 years, and was most common post AD26.COV2·S (4.78/106 doses). Hospitalization was required for 40.3% and 27.2% of myocarditis and pericarditis cases, respectively. A bimodal pattern was found for both myocarditis and pericarditis, with two peaks that coincided temporally, but were reversed in intensity. The first peak was recorded 1-3 days post-vaccination and was more pronounced in myocarditis, while the second was recorded 15-30 days post-vaccination and was more intense in pericarditis. CONCLUSIONS: Myocarditis/pericarditis after COVID-19 vaccination is rare and depicts a bimodal pattern.

The Role of Oral Antivirals for COVID-19 Treatment in Shaping the Pandemic Landscape.

Several vaccines against coronavirus disease 2019 (COVID-19) were developed and made available in a record time, just over a year after the outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) [...].

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.

A Case Series of Acute Pericarditis following COVID-19 Vaccination in the Context of Recent Reports from Europe and the United States

<h4>Background</h4> COVID-19 vaccines were efficacious and safe in clinical trials. We report nine events of acute pericarditis (AP) in eight patients following COVID-19 vaccination with BNT162b2 (6/9), AZD1222 (2/9) and mRNA-1273 (1/9). <h4>Methods</h4> All patients were referred for AP temporally linked with COVID-19 vaccination. Chest pain was the most common clinical manifestation. Alternative etiologies were excluded upon thorough diagnostic work up. AP diagnosis was established according to ESC guidelines. <h4>Findings</h4> Five events occurred after the first vaccine dose and four after the second. The mean age in this cohort was 65.8±10.2 years and the men/women ratio 3/5. All events resolved without sequelae;two events were complicated by cardiac tamponade requiring emergent pericardial decompression. Hospitalization was required in four cases. <h4>Interpretation</h4> Although causality cannot be firmly established, AP has emerged as a possible complication following COVID-19 vaccination. Further investigation is indispensable to fully characterize this new entity.