Pilgrims arrive in St Peter's Square, Vatican City, for prayer with masks to protect themselves from the coronavirus. (Grzegorz Galazka/Mondadori Portfolio/Sipa USA)

Italy could have more than 100,000 cases of coronavirus, an expert has revealed.

Professor Neil Ferguson, of Imperial College London’s faculty of medicine, said he estimates there are “at least” 50,000 to 100,000 cases of the virus in the country, which is one of the worst affected by the virus.

Italy has 2,500 confirmed cases and has suffered 79 deaths.

Prof Ferguson told the BBC’s Today programme that he expects to see measures to tackle the virus rolled out in a matter of days.

“[Italy has] I think it’s over 50 deaths now,” he said, “so those people were probably infected three weeks ago, and for every person who dies we think there might be 100, maybe even 200 people infected.

A man on the Piccadilly line of the London Underground wears a protective facemask. (Kirsty O'Connor/ PA Wire)

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“The lethality of this virus is not completely determined but it’s in that order... so the epidemic is probably doubling every week or so in Italy, so when you put those numbers together, we’d estimate somewhere between 50,000 and 100,000 cases at the moment in Italy.

“At least, it could even be higher, cases may still be being missed even in severe cases.”

He said the UK is “several weeks” behind Italy and is in an earlier stage of an epidemic.

Authorities will be looking to slow the spread of the virus to try to relieve pressure on health systems and the UK government yesterday announced measures to tackle the virus.

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Prof Ferguson said screening air passengers is imperfect and pointed out that Spanish flu spread around the world in the days before commercial air travel.

His figures mean the total number of Italy’s cases could outstrip the total number confirmed worldwide. Just over 93,000 have been reported globally as of Wednesday morning.

Read more: UK coronavirus worst-case scenario of 80% infection rate 'highly unlikely'

After mainland China – where the virus originated – South Korea is the next worst hit with 5,328 confirmed cases and 28 deaths.

Iran reports 77 deaths from its 2,300 officially reported cases.