Ministers were warned last year about the devastating impact of a viral pandemic hitting the UK and urged to stockpile PPE.
Before Covid-19 emerged they were told to put in place plans to monitor and contact-trace infected patients and manage a surge in deaths.
Chief Scientific Adviser Sir Patrick Vallance signed off on the paper, which warned: “A novel pandemic virus could be highly transmissible and highly virulent.
Therefore pandemics significantly pandemics significantly more serious than the reasonable worst case… are possible.”
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It also called for plans to bring home Brits stranded abroad in the event of an outbreak.
The Government has been criticised over its response in all the areas set out in the leaked Cabinet Office 2019 National Security Risk Assessment.
Putting the overall risk of such an outbreak at “very high”, the Whitehall document warned a pandemic would play out in up to three waves.
Each wave would last 15 weeks, “with the peak... at weeks six and seven in each wave”.
Half the population would be infected and show symptoms and a “moderate” pandemic could lead to 65,600 deaths and cost the UK over £2.35trillion, it said.
Shadow Cabinet Office Minister Rachel Reeves said it “raised serious questions about the Government’s planning”.
A Government spokesman said: “We have taken the right steps at the right time, guided at all times by the best scientific advice.”
