Comparisons of the risk of myopericarditis between COVID-19 patients and individuals receiving COVID-19 vaccines: a population-based study

Oscar Hou In Chou, Jiandong Zhou, Teddy Tai Loy Lee, Thompson Kot, Sharen Lee, Abraham Ka Chung Wai, Wing Tak Wong, Qingpeng Zhang, Shuk Han Cheng, Tong Liu, Vassilios S. Vassiliou, Bernard Man Yung Cheung, Gary Tse

Research output: Contribution to journalArticlepeer-review

20 Citations (Scopus)
7 Downloads (Pure)


Background: Both COVID-19 infection and COVID-19 vaccines have been associated with the development of myopericarditis. The objective of this study is to (1) analyse the rates of myopericarditis after COVID-19 infection and COVID-19 vaccination in Hong Kong, (2) compared to the background rates, and (3) compare the rates of myopericarditis after COVID-19 vaccination to those reported in other countries. Methods: This was a population-based cohort study from Hong Kong, China. Patients with positive RT-PCR test for COVID-19 between 1st January 2020 and 30th June 2021 or individuals who received COVID-19 vaccination until 31st August were included. The main exposures were COVID-19 positivity or COVID-19 vaccination. The primary outcome was myopericarditis. Results: This study included 11,441 COVID-19 patients from Hong Kong, four of whom suffered from myopericarditis (rate per million: 326; 95% confidence interval [CI] 127–838). The rate was higher than the pre-COVID-19 background rate in 2019 (rate per million: 5.5, 95% CI 4.1–7.4) with a rate ratio of 55.0 (95% CI 21.4–141). Compared to the background rate, the rate of myopericarditis among vaccinated subjects in Hong Kong was similar (rate per million: 5.5; 95% CI 4.1–7.4) with a rate ratio of 0.93 (95% CI 0.69–1.26). The rates of myocarditis after vaccination in Hong Kong were comparable to those vaccinated in the United States, Israel, and the United Kingdom. Conclusions: COVID-19 infection was associated with significantly higher rate of myopericarditis compared to the vaccine-associated myopericarditis. 

Original languageEnglish
Pages (from-to)1098–1103
Number of pages6
JournalClinical Research in Cardiology
Issue number10
Early online date25 Mar 2022
Publication statusPublished - Oct 2022


  • COVID-19
  • Myocarditis
  • Myopericarditis
  • Pericarditis
  • Vaccine

Cite this