{"doi":"10.7326/m22-2274","title":"Incidence of Myocarditis/Pericarditis Following mRNA COVID-19 Vaccination Among Children and Younger Adults in the United States","abstract":"LettersDecember 2022Incidence of Myocarditis/Pericarditis Following mRNA COVID-19 Vaccination Among Children and Younger Adults in the United StatesFREEKristin Goddard, MPH, Kayla E. Hanson, MPH, Ned Lewis, MPH, Eric Weintraub, MPH, Bruce Fireman, Nicola P. Klein, MD, PhDKristin Goddard, MPHKaiser Permanente Vaccine Study Center, Kaiser Permanente Northern California, Oakland, California, Kayla E. Hanson, MPHMarshfield Clinic Research Institute, Marshfield, Wisconsin, Ned Lewis, MPHKaiser Permanente Vaccine Study Center, Kaiser Permanente Northern California, Oakland, California, Eric Weintraub, MPHImmunization Safety Office, Centers for Disease Control and Prevention, Atlanta, Georgia, Bruce FiremanKaiser Permanente Vaccine Study Center, Kaiser Permanente Northern California, Oakland, California, Nicola P. Klein, MD, PhDKaiser Permanente Vaccine Study Center, Kaiser Permanente Northern California, Oakland, CaliforniaAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/M22-2274 SectionsAboutVisual AbstractPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail Background: Vaccine safety monitoring systems worldwide have reported cases of myocarditis/pericarditis after mRNA-based COVID-19 vaccines (Pfizer-BioNTech and Moderna), especially among younger male persons 0 to 7 days after they received dose 2 (1, 2). Less is known about the incidence of myocarditis/pericarditis after booster doses.Objective: To estimate the incidence of myocarditis/pericarditis during days 0 to 7 after mRNA vaccination by age, sex, dose number, and product.Methods: The Vaccine Safety Datalink (VSD) is a collaborative of 8 integrated health care delivery systems with comprehensive medical records that has conducted active, population-based surveillance of prespecified outcomes after COVID-19 vaccination since December 2020 (1, 3). We identified all potential cases of myocarditis/pericarditis in emergency department and inpatient settings 1 to 98 days after vaccination, using myocarditis/pericarditis–specific ICD-10 codes, among 5- to 39-year-old persons (Table). We validated cases through review of medical records with physician adjudication and classified according to the Centers for Disease Control and Prevention case definition (1).Table. Incidence Rate of Verified Myocarditis/Pericarditis in the 0 to 7 Days After mRNA COVID-19 Vaccination Among Persons Aged 5 to 39 Years by Product, Age Group, Sex, and Dose Number*Findings: From 14 December 2020 through 31 May 2022 (persons 18–39 years) and 20 August 2022 (persons 5–17 years), 320 potential cases of myocarditis/pericarditis were identified 1 to 98 days after 6 992 340 vaccine doses as part of primary series COVID-19 vaccination, with 224 (70%) verified. Of these, 137 (61%) occurred 0 to 7 days after vaccination; 18 were after the first dose (of 3 562 311 doses administered) and 119 were after the second dose (of 3 430 029 doses administered).In all age groups, incidence per million doses 0 to 7 days after vaccination was numerically higher in male than in female persons and after dose 2, although confidence intervals were wide and overlapped across sex for some age groups. Incidence was highest for male adolescents ages 12 to 15 years and 16 to 17 years following dose 2 (Table).From 24 September 2021 through 20 August 2022, 101 potential cases of myocarditis/pericarditis were identified 1 to 98 days after 1 848 723 first booster doses, with 77 (76%) verified with a median onset of 4.5 days after vaccination; 39 cases (51%) were verified in the first week versus 38 during the subsequent 13 weeks.In all age groups, incidence 0 to 7 days after first booster was higher for male compared to female persons, with adolescent males having the highest incidence in 16- to 17-year-olds and in 12- to 15-year-olds. In adults for whom both vaccine products were available, post-booster incidence was higher in male than in female adults and higher","journal":"Annals of Internal Medicine","year":2022,"id":237133,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":63,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9585,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":105911,"name":"Kayla E. Hanson","orcid":"0009-0004-5117-8279","position":1,"is_corresponding":false},{"id":845258,"name":"Ned Lewis","orcid":null,"position":2,"is_corresponding":false},{"id":360574,"name":"Eric Weintraub","orcid":"0000-0003-0375-0504","position":3,"is_corresponding":false},{"id":844217,"name":"Bruce Fireman","orcid":"0000-0003-1652-985X","position":4,"is_corresponding":false},{"id":360572,"name":"Nicola P. Klein","orcid":"0000-0003-1777-4814","position":5,"is_corresponding":false},{"id":844216,"name":"Kristin Goddard","orcid":"0000-0001-8804-2958","position":0,"is_corresponding":true}],"reference_count":3,"raw_metadata":null,"created_at":"2026-07-19T00:22:08.925400Z","pmid":"36191323","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}