Understanding motivation and experience in participating in a paediatric SARS-CoV-2 serosurvey, in Australia

Serosurveys are considered as a valuable tool in estimating population immunity and infection rates but recruitment of children to provide paediatric estimates can be challenging. A novel approach of sampling children undergoing anaesthesia was utilised for a SARS-CoV-2 serosurvey in Australian children and we explore the reasons for participation, feedback on the approach and importance of research into Coronavirus Diseases 2019 (COVID-19). This cross-sectional, nationally representative serosurvey recruited children aged 0–19 years undergoing an anaesthetic procedure from eight paediatric hospitals between 8 June to 31 August 2022. Guardians or participants (18–19 years) were invited, upon receiving their results, to provide an online survey. A qualitative thematic approach was used to analyse the free-text responses. Feedback was provided by 15.7 % (323/2046) participants. Reasons for participating included contributing to research (67/323 responders) and curiosity about SARS-CoV-2 immunity (65/323 responders). The opportunistic sampling method was well-received, convenient, and minimally disruptive. Responders emphasised the importance of research on COVID-19 in children, highlighting the need to understand the long-term impact of the virus and to inform vaccination decisions. There are challenges in conducting ethical, low-burden cross sectional serosurveys in children in a vast country like Australia. This approach not only contributed to the collection of a large paediatric sample size but also supports the use of this method in future serosurveys. • SARS-Cov-2 serosurveys in children used sera from children undergoing anaesthetic procedures • Opportunistic sampling during anaesthesia was minimally disruptive and effective for future serosurveys. • Participation was driven by research interest, curiosity, and the convenience of collection • Responders were keen on research on long-term effects and to guide vaccination decisions.