Data from the National COVID-19 Infection Survey, done in partnership between the University of Oxford, the Office of National Statistics, Public Health England, University of Manchester and the Wellcome Trust, has revealed detailed characteristics of England’s coronavirus pandemic, including which factors have contributed most to case numbers over different phases and the prevalence of asymptomatic infections.
The study, published today in The Lancet Public Health, illustrates the substantial drop off in cases over the summer, before cases began rising again from the end of August, a trend that has continued through the autumn. The data analysed was from 26 April to 1 November 2020, using a representative sample of private households in England (totalling 1,191,170 coronavirus test results from 280,327 individuals).
Working outside the home and having a patient-facing role in health or social care was most associated with a positive COVID-19 test in the spring 2020 peak of the pandemic, while age (young people under 25) was the most important factor for positive tests in the autumn 2020 peak. The reasons for this difference could be attributed to changes in behaviour and movement. A possible explanation for the lower rates in vulnerable groups during the second peak is the development of antibodies in those who previously had the virus, as well as better measures to reduce the chance of infection for key workers.