LONDON (REUTERS) - Covid-19 cases rose in London during the last weeks of a national lockdown even as prevalence in England as a whole fell, a study said on Tuesday (Dec 15), adding that a planned relaxation of rules over Christmas posed risks.
London will move into England's highest tier of coronavirus restrictions from midnight on Wednesday morning after an exponential rise in cases.
When a national lockdown ended on Dec 2, London was not placed under the strictest restrictions in the three-tier system.
But while the prevalence of Covid-19 cases fell in England by around 30 per cent during lockdown between Nov 13 and Dec 3, prevalence was rising in London, according to Imperial College London's REACT-1 prevalence study.
Nationally the prevalence of Covid-19 infection, which had averaged 1.3 per cent of the population between mid-October and early November, fell to an average of 0.94 per cent during the lockdown period in England and was last at 0.91 per cent.
But in London prevalence rose from 0.98 per cent in mid-November to 1.21 per cent in early December.
"During the first half of lockdown our study showed that infections were on a clear downward trajectory, but we're now seeing a levelling off, driven by clusters of infections in certain regions and age groups," said Mr Paul Elliott, director of the programme at Imperial.
The authors of the study added that the prevalence was highest among secondary school children, and warned that a planned easing of rules over Christmas came with risks.
The four nations of the United Kingdom will relax restrictions to allow up to three households to meet at home for five days over Christmas.
"Most scientists are concerned... the Christmas period is characterised by mixing with much more at-risk members of our families," Dr Steven Riley, Professor of Infectious Disease Dynamics at Imperial, told reporters.
"I would emphasise that the government's allowing this, but not saying that you should do it."