Increased lockdown measures have come into force in England with around half the country now under heavier restrictions.
The new system - dubbed "Local Covid Alert Levels" - divides England into "medium" (Tier 1), "high" (Tier 2) and "very high" (Tier 3) risk areas depending on the current rate of Covid-19 infections - though the government has not released the exact thresholds for triggering lockdown.
Most of the country is covered by the medium alert level, which consists of the current national measures for England, including the Rule of Six and 10pm curfew on pubs and restaurants, while the additional high level reflects the restrictions already in place in many areas as part of local lockdowns.
These are primarily aimed at reducing household-to-household transmission by reducing all mixing by households or support bubbles indoors, while the Rule of Six continues to apply outdoors.
However, the Government has also introduced a very high alert level - which includes Lancashire, Greater Manchester, South Yorkshire and the city of Liverpool - for areas where transmissions rates are rising most rapidly, bringing with it a "baseline" of restrictions including banning social mixing indoors and private gardens and closing pubs and bars.
Local areas will then be able to choose from a set of additional measures that include further restrictions on hospitality and leisure sectors.
The Prime Minister insists that retail, schools and universities will remain open under all alert levels.
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Why was it necessary?
Professor Jonathan Van-Tam, England’s Deputy Chief Medical Officer, warned that it was of "concern" that coronavirus was "heating up" in more of England, with infections spreading into more vulnerable age groups.
Prof Van-Tam said: "This is a nationwide phenomenon now that rates are changing upwards across the UK."
He also warned that the virus was now spreading from younger age groups into those aged over 60.
"And this is again of significant concern... because of course the elderly suffer a much worse course with Covid-19, they are admitted to hospital for longer periods, and they are more difficult to save,” he said.
According to the data from Public Health England, the rate of infection among people aged 80 and above in the North West rose from 40.5 to 72.8 per 100,000 in the space of four weeks.
It follows a rapid rise in infections among younger age groups. In the same period infections among those aged between 20 and 29 in the region more than doubled - from 102.5 to 236.9.
More hospitalisations for Covid-19 followed in the wake of rising infections in both the North West and North East and Yorkshire, with new admissions per one million people standing at around 23 and 16 respectively, according to data up to October 9.
Though hospitals have not yet reached capacity, NHS Nightingale hospitals in Manchester, Sunderland and Harrogate have been asked to get ready to take patients.
However, cases are rising across the country, with data from the four nations of the UK showing almost 40 per cent of local authorities seeing significant rises in rates of infection.
Professor Van Tam insisted the issue was not confined to the North of England.
Responding to the media he said: "You have worried me now that I might have presented a bipolar picture that Covid-19 is a problem in the North and not a problem in the South.
"On the contrary, the epidemic this time has clearly picked up pace in the North of England earlier than it did in the first wave and that almost certainly relates to the fact the disease levels in the North, and certainly in the North West, never dropped as far in the summer as they did in the South.
"But pretty much all areas of the UK are now seeing growths in the infection rate."
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