Could over half of the UK have already been infected by COVID-19?
Recently a preprint of a publication from Oxford University proposed that up to 68% of the UK population may have been infected by 19th March 2020. They also proposed that transmission started in late January. This preprint has not been peer-reviewed yet, which is an in-depth evaluation of publications by fellow members in the same field, however, it seems to have picked up a rather large media coverage.
The publication urged for the need for large scale serological antibody test surveys for Covid-19 infection, results from confirmed infected individuals and open access to data from blood banks. With this data, they hope to determine how many people require hospitalisation in the near future and the extent of herd immunity which could help to shape future public health policy.
Now by no means am I a specialist in Public Health or Epidemiology (the study of how often diseases occur in different groups of people and why). I was a second-year medical student have been taught the fundamentals of Epidemiology and have practised reading scientific writing such as this. I will be giving you my insight into this publication however we will know more once the peer review process is complete, the paper is published and finally is either proven or disproven.
The statistic showing that 68% of the UK population would have been affected by mid-March was run assuming that only one in 1,000 people infected will need hospitalisation. One of the scenarios that were run through the model suggests the first case of Covid-19 in the UK may have been on 27th January 2020, 38 days before the first reported UK death.
Now if this study is proven to be correct this would mean that the governments initial herd immunity strategy may come to fruition faster than anticipated. If the virus had already affected as many people as proposed the UK would have already acquired a much greater amount of herd immunity than current estimates suggest and so would have huge implications for the current policy.
This study is highly controversial however once more information is available, we will be able to determine whether this study is overly optimistic or could shape the future government policies.
Article by Sajan
Oxford Prelease - https://www.medrxiv.org/content/10.1101/2020.03.24.20042291v1