Has over half of the UK already been exposed to COVID-19?
Bulletin 2 | Stuart McDonald
Media reporting of a new paper published by a team at the University of Oxford has focussed on a suggestion that over half of the UK may have already been exposed to COVID-19. The paper does not (and does not claim to) provide evidence of this. What the paper does demonstrate is the current uncertainty over the proportion of the population of the UK and Italy that may have been exposed to COVID-19, and the need for large-scale testing to reduce that uncertainty.
This group supports the suggestion that such testing should be carried out, but we are concerned that the suggestion that much of the population may be immune to the virus could undermine key public health messages about social distancing.
The paper does include combinations of model parameters which assume a low proportion of the population vulnerable to severe disease which in turn implies a very high prevalence of the virus. We consider these to be the least plausible of the parameter choices illustrated.