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       A health worker administers a COVID-19 vaccine booster shot at Midland House in Derby, Britain, on Sept. 20, 2021.

       CARL RECINE/Reuters

       Britain reported the highest number of new COVID-19 cases in three months on Monday as the number of infections reached levels last seen when lockdown restrictions were in place in England during the summer.

       Infection numbers in Britain are currently much higher than in other western European countries and have risen more 60 per cent in the past month.

       Government data showed there were 49,156 new cases of coronavirus, up from 45,140 on Sunday, and the highest daily total since July 17.

       Britain lifted the last remaining social distancing restrictions to contain the virus on July 19 when pubs and restaurants were allowed to operate at full capacity and nightclubs reopened their doors.

       The number of cases has been steadily rising since schools returned from their summer holidays last month with studies showing infections rising in children even as there has been a fall in prevalence among adults.

       However, with over two-thirds of the adult population fully vaccinated, this has so far dramatically reduced the risk of hospitalization and death.

       Overall, Britain has had one of the highest coronavirus death tolls in the world, with more than 138,629 deaths.

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