Swiss Medical Weekly (2022) “Erratum to: High SARS-CoV-2 seroprevalence but no severe course of COVID-19 disease among people on opioid agonist treatment in Zurich: a cross-sectional study: Erratum to Swiss Med Wkly. 2022;152:w30122 (DOI 10.4414/smw.2022.w30122)”, Swiss Medical Weekly, 152(0506), p. w30149. doi: 10.4414/SMW.2022.w30149.