About the Authors

Ulrike Baum

Contributed equally to this work with: Ulrike Baum, Eero Poukka

Roles Conceptualization, Formal analysis, Methodology, Writing – original draft, Writing – review & editing

eero.poukka@thl.fi (EP); ulrike.baum@thl.fi (UB)

Affiliation Infectious Disease Control and Vaccinations Unit, Department of Health Security, Finnish Institute for Health and Welfare (THL), Helsinki, Finland

Eero Poukka

Contributed equally to this work with: Ulrike Baum, Eero Poukka

Roles Formal analysis, Writing – original draft, Writing – review & editing

eero.poukka@thl.fi (EP); ulrike.baum@thl.fi (UB)

Affiliation Infectious Disease Control and Vaccinations Unit, Department of Health Security, Finnish Institute for Health and Welfare (THL), Helsinki, Finland

Arto A. Palmu

Roles Conceptualization, Formal analysis, Writing – review & editing

Affiliation Population Health Unit, Department of Public Health and Welfare, Finnish Institute for Health and Welfare (THL), Tampere, Finland

Heini Salo

Roles Formal analysis, Writing – review & editing

Affiliation Infectious Disease Control and Vaccinations Unit, Department of Health Security, Finnish Institute for Health and Welfare (THL), Helsinki, Finland

Toni O. Lehtonen

Roles Data curation, Writing – review & editing

Affiliation Infectious Disease Control and Vaccinations Unit, Department of Health Security, Finnish Institute for Health and Welfare (THL), Helsinki, Finland

Tuija Leino

Roles Conceptualization, Data curation, Formal analysis, Investigation, Supervision, Writing – review & editing

Affiliation Infectious Disease Control and Vaccinations Unit, Department of Health Security, Finnish Institute for Health and Welfare (THL), Helsinki, Finland

Competing Interests

The current study received no external funding outside THL. AAP is an investigator in studies (not related to the current study nor COVID-19) for which the Finnish Institute for Health and Welfare has received research funding from Sanofi Pasteur (influenza vaccine trial), GlaxoSmithKline (pneumococcal vaccine trial) and Pfizer (streptococcal study). There are no competing interests relating to employment, consultancy, patents, products in development, or marketed products. All other authors declare no conflict of interest. This does not alter our adherence to PLOS ONE policies on sharing data and materials.