The number of Hertfordshire residents hospitalised with Covid-19 rose by almost a third in the last week of verified data – and the numbers look set to increase in the coming weeks.

New NHS figures show that on Monday, December 14, 199 hospital beds were occupied by coronavirus patients across four Herts hospital trusts.

In the week leading up to December 15, Hertfordshire’s overall infection rate rose by 83 per cent, from 168 cases per 100,000 people to 309.

This means hospitalisation rates would be expected to continue rising over Christmas and New Year.

It typically takes a week or so for a patient’s symptoms to grow severe enough to require hospital treatment. This means hospitalisation rates are typically a week or two behind infection rates.

Prime Minister Boris Johnson announced on Saturday that he had seen evidence that a new strain of the disease, up to 70pc more contagious, was ripping through London and the home counties.

Hospitalisations had already been rising in the county with increasing speed.

On November 30, there were 122 beds occupied across four NHS trusts.

A week later, on December 7, that had risen by 24 per cent to 151.

A week later, on December 14, it had risen by another 32pc to 199.

Deaths were also already rising.

In the week up to November 13, there were 17 Covid deaths registered in the county.

Three weeks later, in the week up to December 4 – the most recent death figures – it had doubled to 34 deaths in seven days.

After Mr Johnson’s announcement on Saturday, Hertfordshire was placed under new “Tier 4” restrictions and planned relaxations of coronavirus rules for Christmas were cancelled.

David Williams, leader of Hertfordshire County Council, said: “It is vital we follow the new rules to prevent it spreading.”

On December 14, 119 patients were being cared for by the West Hertfordshire Hospitals NHS Trust, which runs Watford General Hospital.

Another 58 patients were being treated at the East and North Hertfordshire NHS Trust, which runs Lister Hospital.

The Hertfordshire Partnership University NHS Foundation Trust was caring for seven patients, and the Hertfordshire Community NHS Trust for another 15.