Transmission, pathogenesis and immunogenicity of SARS-CoV-2 in frontline healthcare workers: a national longitudinal cohort of 1320 participants

We want to know how many and which doctors and nurses have been infected with the virus (SARS-Cov2) that causes COVID-19 with or without symptoms. We have been collecting blood from 1320 healthcare workers on a weekly basis during the pandemic. We are analysing blood for antibodies against the virus. We will continue to measure their blood 10 times up to 6 months after the lockdown is lifted. This study will also allow us to know how the levels of antibodies in blood change over time and which of the antibodies are able to fight the virus. We will investigate whether individual characteristics, including genetics, age, sex, ethnicity, affect the length of time for which antibodies remain in blood at high enough levels to fight the virus. Among the doctors and nurses in our study we have people who have had a severe infection, others who have had mild symptoms and many with no symptoms. We will put all this information together to work out how healthcare workers develop antibodies against the virus and if this is affected by the severity of the symptoms is important. We will measure proteins and gene expression to identify how to effectively vaccinate and treat healthcare workers.