The impact of believing you have had COVID-19 on behaviour: Cross-sectional survey
Authors: Smith Louise E. , Mottershaw Abigail L. , Egan Mark , Waller Jo , Marteau Theresa M. , Rubin G James 
Published: May 2020

ABSTRACTObjectivesTo investigate whether people who think they have had COVID-19 are less likely to engage in social distancing measures compared with those who think they have not had COVID-19.DesignOn-line cross-sectional survey.SettingData were collected between 20th and 22nd April.Participants6149 participants living in the UK aged 18 years or over.Main outcome measuresPerceived immunity to COVID-19, self-reported adherence to social distancing measures (going out for essential shopping, nonessential shopping, and meeting up with friends/family; total out-of-home activity), worry about COVID-19 and perceived risk of COVID-19 to oneself and people in the UK. Knowledge that cough and high temperature / fever are the main symptoms of COVID-19.ResultsIn this sample, 1493 people (24.3%) thought they had had COVID-19. Only 245 (4.0%) reported receiving a test result saying they had COVID-19. Reported test results were often incongruent with participants’ belief that they had had COVID-19. People who believed that they had had COVID-19 were: more likely to agree that they had some immunity to COVID-19; less likely to report adhering to social distancing measures; less worried about COVID-19; and less likely to know that cough and high temperature / fever are two of the most common symptoms of COVID-19.ConclusionsThe number of people in the UK who think they have already had COVID-19 is about twice the rate of current prevalence estimates. People who think that they have had COVID-19 may contribute to transmission of the virus through non-adherence to social distancing measures. Clear communications to this growing group are needed to explain why protective measures continue to be important and to encourage sustained adherence.COPYRIGHTThe Corresponding Author has the right to grant on behalf of all authors and does grant on behalf of all authors, an exclusive licence (or non exclusive for government employees) on a worldwide basis to the BMJ Publishing Group Ltd to permit this article (if accepted) to be published in BMJ editions and any other BMJPGL products and sublicences such use and exploit all subsidiary rights, as set out in our licence.FUNDING SOURCESJW is funded by a career development fellowship from Cancer Research UK (ref C7492/A17219). LS and GJR are supported by the National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in Emergency Preparedness and Response at King’s College London in partnership with Public Health England (PHE), in collaboration with the University of East Anglia and Newcastle University. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care, Public Health England. Data collection was funded via a block Government grant to the Behavioural Insights Team.COMPETING INTEREST STATEMENTAll authors have completed the Unified Competing Interest form (available on request from the corresponding author) and declare: ALM and ME report grants from government partners to the Behavioural Insights Team, during the conduct of the study, JW reports grants from Cancer Research UK, during the conduct of the study; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years, no other relationships or activities that could appear to have influenced the submitted work.TRANSPARENCY DECLARATIONThe authors affirm that the manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as originally planned have been explained.AUTHOR CONTRIBUTION STATEMENTThe study was conceptualised by LS, GJR, JW and TMM. AM and ME completed data collection. LS analysed the data. All authors contributed to, and approved, the final manuscript.WHAT IS ALREADY KNOWN ON THIS TOPICDuring the COVID-19 pandemic, multiple countries, including the UK, have introduced “lockdown” measures.The World Health Organization has warned against using the results of antibody tests to issue “immunity passports” due to fears that those who test positive for antibodies may stop adhering to protective measures.There is no research investigating adherence to protective measures among those who think they have had COVID-19.WHAT THIS STUDY ADDSThis is the first study investigating behavioural differences between those who think they have had COVID-19 and those who do not.About twice as many people think they have had COVID-19 than prevalence estimates suggest.Results suggest that there may be a high degree of self-misdiagnosis within those who think they have had COVID-19.Those who think they have had COVID-19 were more likely to think they were immune to COVID-19, and less likely to adhere to social distancing measures.