Clinical Spectrum of Children With Parvovirus B19–Associated Acute Myocarditis
Abstract
BACKGROUND: Parvovirus B19 is a DNA virus transmitted via respiratory droplets, commonly causing erythema infectiosum in children but also implicated in acute myocarditis. In 2024, an outbreak of parvovirus B19 infections was reported across Europe and the United States. Despite growing awareness, data on the clinical features and outcomes of children with parvovirus B19–associated acute myocarditis remain limited. METHODS: This multicenter retrospective observational study reviewed medical records of pediatric patients (<18 years of age) admitted with acute myocarditis to 11 Italian tertiary pediatric cardiac centers between January 1, 2022, and October 31, 2024. Of 217 cases, 66 had confirmed parvovirus B19 DNA in plasma (PVB19 + ), whereas 82 with negative parvovirus B19 testing served as a comparator group (PVB19 − ). Population-based incidence trends of pediatric myocarditis were also evaluated in the Lombardy region from 2004 through 2024. RESULTS: Among PVB19 + acute myocarditis cases, 58 of 66 (87.9%) were admitted in 2024. The median age was 32 months, with 51 of 66 (77.2%) ≤7 years of age, and 36 of 66 (54.5%) were boys. Median plasma viral load was 34 411 copies/mL, whereas only 30 of 56 (53.6%) had immunoglobulin M (IgM) positivity. Among 26 of 66 (39.4%) with available histology, 23 (88.4%) had lymphocytic myocarditis, and parvovirus B19 DNA was identified in 84.0% of myocardial specimens. Among 25 of 65 (38.4%) who underwent genetic testing, none had pathogenic or likely pathogenic variants. Overall, 13 of 66 (19.7%) died, underwent heart transplantation, or received a durable left ventricular assist device (in total, there were 6 deaths, 5 durable left ventricular assist devices, and 5 transplantations) compared with 1 of 82 (1.2%) among PVB19 − acute myocarditis (one patient who received a durable left ventricular assist device and later underwent transplantation; P <0.001). A marked increase in regional and institutional myocarditis incidence in pediatric acute myocarditis was observed in 2024, predominantly in children ≤7 years of age, driven by PVB19 + cases. CONCLUSIONS: During the 2024 parvovirus B19 outbreak, pediatric PVB19 + acute myocarditis cases surged in Italy and were associated with severe outcomes. A high index of suspicion is required for diagnosis, and early virological testing is essential to guide management and potentially improve outcomes.
Article Details
Authors (44)
Enrico Ammirati
De Gasperis Cardio Center and Transplant Center, ASST Grande Ospedale Metropolitano Niguarda, Milano, Italy (E.A., G. Colombo, S.N., F.A., A.G., M.G.M.).
Giacomo Veronese
Pediatric Intensive Care Unit, ASST Papa Giovanni XXIII, Bergamo, Italy (G.V., I.P., G.B.C., E.B.).
Francesca Raimondi
Giuseppe Alberto Annoni
Pediatric and Congenital Cardiology and Cardiac Surgery, Regina Margherita Children’s Hospital, Azienda Ospedaliero-Universitaria Città della Salute e della Scienza di Torino, Torino, Italy (G.A.A., S.B., C.P.N.).
Domenico Sirico
Department of Women’s and Children’s Health, University of Padua, Padova, Italy (D.S., G.D.S., E.R.).
Francesco Bianco
Department of Pediatric and Congenital Cardiology and Cardiac Surgery, Azienda Ospedaliero Universitaria “Ospedali Riuniti,” Ancona, Italy (F.B., V.B., S.F.).
Alessio Franceschini
Gessica Ingrasciotta
Heart Failure, Transplant and Mechanical Assist Device Unit, IRCCS Bambino Gesù Children’s Hospital, Roma, Italy (A.F., G.I., A.A., R.A.).
Giovanni Meliota
Department of Pediatric Cardiology, Giovanni XXIII Pediatric Hospital, Bari, Italy (G.M., U.V., M.L.).
Guglielmo Capponi
Fondazione G. Monasterio CNR-Regione Toscana, Massa, Pisa, Italy (G. Capponi, N.A., P.M.).
Isabella Pellicioli
Pediatric Intensive Care Unit, ASST Papa Giovanni XXIII, Bergamo, Italy (G.V., I.P., G.B.C., E.B.).
Gaia Biancamaria Chiesa
Pediatric Intensive Care Unit, ASST Papa Giovanni XXIII, Bergamo, Italy (G.V., I.P., G.B.C., E.B.).
Carlo Beretta
Giada Colombo
Giovanni Di Salvo
Sandra Nonini
De Gasperis Cardio Center and Transplant Center, ASST Grande Ospedale Metropolitano Niguarda, Milano, Italy (E.A., G. Colombo, S.N., F.A., A.G., M.G.M.).
Francesca Aresta
De Gasperis Cardio Center and Transplant Center, ASST Grande Ospedale Metropolitano Niguarda, Milano, Italy (E.A., G. Colombo, S.N., F.A., A.G., M.G.M.).
Luca Ragni
Pediatric Cardiology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy (L.R., T.H., M.B.).
Tammam Hasan
Pediatric Cardiology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy (L.R., T.H., M.B.).
Maurizio Brighenti
Pediatric Cardiology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy (L.R., T.H., M.B.).
Giovanna Travi
Infectious Diseases, ASST Grande Ospedale Metropolitano Niguarda, Milano, Italy (G.T.).
Olivia Leoni
Paul Stefan Vrabie
Epidemiological Regional Observatory, Lombardy Region, Milano, Italy (O.L., P.S.V., M.E.).
Michele Ercolanoni
Epidemiological Regional Observatory, Lombardy Region, Milano, Italy (O.L., P.S.V., M.E.).
Giuseppe Limongelli
Emanuele Monda
Maria Giovanna Russo
Department of Translational Medical Sciences, University of Campania “Luigi Vanvitelli,” Monaldi Hospital, Napoli, Italy (G.L., E.M., M.G.R.).
Alessandra Corato
Pediatric Cardiology Unit, ASST Grande Ospedale Metropolitano Niguarda, Milano, Italy (A.C.).
Elena Reffo
Department of Women’s and Children’s Health, University of Padua, Padova, Italy (D.S., G.D.S., E.R.).
Valentina Bucciarelli
Department of Pediatric and Congenital Cardiology and Cardiac Surgery, Azienda Ospedaliero Universitaria “Ospedali Riuniti,” Ancona, Italy (F.B., V.B., S.F.).
Sergio Filippelli
Department of Pediatric and Congenital Cardiology and Cardiac Surgery, Azienda Ospedaliero Universitaria “Ospedali Riuniti,” Ancona, Italy (F.B., V.B., S.F.).
Susanna Breviario
Pediatric and Congenital Cardiology and Cardiac Surgery, Regina Margherita Children’s Hospital, Azienda Ospedaliero-Universitaria Città della Salute e della Scienza di Torino, Torino, Italy (G.A.A., S.B., C.P.N.).
Carlo Pace Napoleone
Pediatric and Congenital Cardiology and Cardiac Surgery, Regina Margherita Children’s Hospital, Azienda Ospedaliero-Universitaria Città della Salute e della Scienza di Torino, Torino, Italy (G.A.A., S.B., C.P.N.).
Ugo Vairo
Department of Pediatric Cardiology, Giovanni XXIII Pediatric Hospital, Bari, Italy (G.M., U.V., M.L.).
Maristella Lombardi
Department of Pediatric Cardiology, Giovanni XXIII Pediatric Hospital, Bari, Italy (G.M., U.V., M.L.).
Nadia Assanta
Fondazione G. Monasterio CNR-Regione Toscana, Massa, Pisa, Italy (G. Capponi, N.A., P.M.).
Pietro Marchese
Fondazione G. Monasterio CNR-Regione Toscana, Massa, Pisa, Italy (G. Capponi, N.A., P.M.).
Paolo Ferrero
Pediatric Cardiology, Heart Lung and Vascular Department, AOUI Verona, Italy (P.F.).
Flavio Luciano Ribichini
Heart Lung and Vascular Department, AOUI Verona, and University of Verona, Italy (F.L.R.).
Andrea Garascia
De Gasperis Cardio Center and Transplant Center, ASST Grande Ospedale Metropolitano Niguarda, Milano, Italy (E.A., G. Colombo, S.N., F.A., A.G., M.G.M.).
Michele Giovanni Mondino
De Gasperis Cardio Center and Transplant Center, ASST Grande Ospedale Metropolitano Niguarda, Milano, Italy (E.A., G. Colombo, S.N., F.A., A.G., M.G.M.).
Antonio Amodeo
Rachele Adorisio
Heart Failure, Transplant and Mechanical Assist Device Unit, IRCCS Bambino Gesù Children’s Hospital, Roma, Italy (A.F., G.I., A.A., R.A.).
Ezio Bonanomi
Pediatric Intensive Care Unit, ASST Papa Giovanni XXIII, Bergamo, Italy (G.V., I.P., G.B.C., E.B.).