Written Evidence Submitted by Professor Mark Woolhouse, University of Edinburgh, follow up

(CLL0011)

Dear Mr Clark,

Thank you for inviting me to give evidence this morning.

I am writing to add to the discussion about modelling tests and trace, as I failed to find an opportunity to do so during the session.

“I cannot comment on what modelling results were communicated between SAGE and Ministers in March, but I can comment on the context at the time.

Around March 14th the CMO announced the decision to focus the then limited testing capacity available on hospital settings. It was clearly understood that we did not have the capacity to test widely in the community at the time. With or without a mathematical model, my judgement is that given the epidemic was starting to grow rapidly (doubling times fell as low as 3-4 days) there was no realistic possibility of growing testing capacity fast enough to catch up. We went into lockdown only 9 days later. The decision to grow test capacity would have to have been taken much earlier to have made any material difference to the course of the UK epidemic. I believe the Imperial College model discussed this morning was published on March 16th, 7 days before lockdown and far too late for a test and trace response to be implemented effectively even if that option had been modelled.”

I hope this is helpful and I am happy for this comment to be recorded if you wish.

Yours sincerely,

Mark Woolhouse

(October 2020)