A flu pandemic would result in 820,000 deaths under a reasonable worst-case scenario, a government document says.
The toll appears in a national security risk assessment comparing a potential influenza pandemic with coronavirus data that was available in February, the time the report was prepared.
The document was discussed by the government’s Scientific Advisory Group for Emergencies (Sage) that month.
In it, a table compares the government’s reasonable worst-case scenario for a flu pandemic next to the information it had on COVID-19.
It projects the number of excess deaths in a flu pandemic would be 820,000 under this scenario.
Excess deaths is when the number of fatalities are higher than would be expected for a given time of the year.
The report also states that because the projected excess deaths from COVID-19 were unknown, the government should use its flu pandemic assumption.
Under the reasonable worst-case scenario, a flu pandemic would lead to 1.3m people needing hospital care, or 4% of people with symptoms, with 328,000 requiring the highest level of critical care – about 1% of patients with symptoms.
The report also suggested 3.6m people would need hospital for COVID-19 treatment, or 11% of symptomatic patients, with 541,200 needing the highest level of critical care, or 1.65% of people displaying symptoms.
Both conditions were thought to produce symptoms in half the population, but with possibly 80% of the population – including asymptomatic people – ultimately being infected with COVID-19 and 85% being infected in a flu pandemic.
The document does not make reference to how these assumptions would change under various suppression strategies like lockdowns.
It also examined how workplaces would be affected in a flu pandemic, estimating that in the reasonable worst-case scenario, up to 20% of the national workforce could be absent during the peak weeks of an outbreak.
Half of employees would need time off either due to illness or to care for people, the document states, which would be higher if schools were shut.
It was thought COVID-19 would lead to at least 15% of employees needing absence during the coronavirus peak.
The document was considered by Sage on 27 February, the government website states.
That was in the very early stage of recorded COVID-19 deaths in Europe, with Italy’s fatalities only beginning to rise that week.
“This evidence was often complied [sic] very rapidly during a fast-moving response and should be viewed in this context,” the website adds.
“The paper presented here is the best assessment of the evidence at the time of writing, and the conclusions were formed on this basis.
“As new evidence or data emerges, SAGE updates its advice accordingly. Therefore, some of the information in this paper may have been superseded at a later date.”
There have been more than 265,000 confirmed COVID-19 cases in the UK since its outbreak began and at least 37,000 deaths associated with the disease.
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