LONDON - Nearly eight million people in Britain could be hospitalised due to the coronavirus epidemic, with the outbreak expected to last until spring next year, The Guardian reported.

Citing a secret Public Health England (PHE) document for senior National Health Service (NHS) officials, the newspaper said the report outlines the potential scale of the outbreak.

"As many as 80 per cent of the population are expected to be infected with Covid-19 in the next 12 months, and up to 15 per cent (7.9 million people) may require hospitalisation," The Guardian cited the document as saying, adding that four in five people "are expected" to be infected.

Downing Street said the PHE briefing outlined a reasonable worst-case scenario, BBC reported.

The report was prepared by PHE's emergency preparedness and response team and has been shared with hospital administrators and senior doctors in the NHS.

The Independent reported that PHE said it would not comment on the contents of the document.

The document revealed that of the five million critical staff working in essential services and critical infrastructure, roughly 500,000 will fall ill and be off work during a month-long peak of the epidemic.

The five million includes one million NHS staff and 1.5 million workers in social care.

The report also warned that Britain's health service cannot cope with the large number of people with symptoms who need to be tested because laboratories are "under significant demand pressures".

"From now on, only the very seriously ill who are already in hospital and people in care homes and prisons where the coronavirus has been detected will get tested," it said.

It added testing services are under such strain that even NHS staff will not be swabbed, despite the risk of them passing the virus to patients.

The decision not to test every case of coronavirus runs contrary to the advice from World Health Organisation (WHO) director-general Tedros Adhanom Ghebreyesus to "find, isolate, test and treat every case, to break the chains of transmission".

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"You can't fight a virus if you don't know where it is," he said. "Every case we find and treat limits the expansion of the disease."

Britain has taken a distinctly different approach to tackling the coronavirus from continental Europe, which has seen numerous countries imposing stringent lockdowns to try to slow the spread of the disease.

Britain had 1,372 confirmed cases and 35 deaths from the coronavirus as of Sunday (March 15).

Critics have accused the government of not acting quickly enough to contain the spread, but the government has said that it is taking the advice of experts, including behavioural scientists, on when to deploy the measures.