Coronavirus infections exploded in December, with some neighbourhoods seeing rises of almost 2,000pc last month.

Public Health England data up to December 30 shows Norfolk’s rate is now at 416.2 per 100,000; four times higher than at the start of December.

Suffolk's rate has also shot up from 67.2 to 381.2 in the same period.

The new, more infectious strain of Covid-19 has been blamed for the rise and parts of Great Yarmouth and South Norfolk are now bearing the brunt of infections.

Bradwell North in Great Yarmouth has the highest rate in the county, with more than 1,000 cases per 100,000 at the end of December.

The second highest rate is currently in the area of Mulbarton, Tasburgh & Saxlingham Nethergate with infections of 947 per 100,000 people.

It comes as figures reveal one in four close contacts of people with the virus are not being reached by the test and trace regime in Norfolk.

In the seven-day period ending on December 23, 28,313 close contacts were identified, but only 73.5pc of those were reached by NHS Test and Trace, compared to the England figure of 92.5pc for the same period.

It means in the week leading up to Christmas, 7,500 people in Norfolk were not told they had been in contact with someone with the virus.

How the virus spread

The new strain of the virus swept across the region in December, with experts believing it is responsible for around a third of all new infections in Norfolk.

But at the start of the month the picture was very different.

In the week leading up to December 2, 31 neighbourhoods in the county, with populations of around 8,000 people each, had rates of zero.

Infection hotspots at that point existed in the Marshland, Walpole and Walton area of West Norfolk, which had an infection rate of 410.5 per 100,000 and Heartsease, where a rate of 430.6 was found because of an outbreak at HMP Norwich.

A week later, by December 9, the number of areas recording rates of zero fell to just 14 neighbourhoods.

Rates of infection remained stable in hotspots like Norwich and West Norfolk, but as the virus spread further afield, neighbourhoods that had returned rates of zero the week before saw huge increases.

In the Bradwell North area of Yarmouth, the infection rate leapt from zero to 377.9 per 100,000 in one week.

Swaffham also saw a surge, with cases rising from zero to 145 per 100,000.

Then, by December 16, only six neighbourhoods were holding out with a zero rate of infections, mainly in the north of the county.

Meanwhile, Swaffham’s rate swelled to 483.2 while in King’s Lynn and West Norfolk Fairstead and Springwood’s rate doubled to 554.1 per 100,000.

All areas of Norfolk and Waveney were in the grip of the virus by the week ending December 23. The lowest rate of infection at that point was in Halesworth and Wangford, where 55.5 per 100,000 was recorded.

By then over a quarter of all neighbourhoods across Norfolk and Waveney had a rate of 300 per 100,000 or higher.

The latest Public Health England data runs to the week ending December 30, and the stark figures show just how far the virus travelled in one month.

Of the 215 areas in Norfolk and Waveney, 113 have seen rates double since the start of December.

All areas of Norfolk and Waveney now have rates of more than 100 per 100,000. The area with the lowest rate is Thurlton, Haddiscoe & Geldeston in Waveney, where 136.8 was recorded for the week.

In Norwich, Mile Cross has seen its infection rate rise by 1,969pc in the month of December, from 27.2 to 562.8. The Bowthorpe and West Earlham areas of the city saw a rise of 1,166pc in the same month, from 49.8 to 630.5.

Another big rise was seen in the Gaywood Chase & Old Gaywood neighbourhood of King’s Lynn and West Norfolk, where cases rose by 1,033pc from 41.3 to 467.9 per 100,000 in December.

And in Attleborough in Breckland, where the case rate rose from 40.2 to 411.9 per 100,000 – a rise of 1,025pc.

The stark figures have ended all hope of restrictions easing until the new strain is brought under control through the fresh lockdown and vaccines.