There were 42 new positive cases of Covid-19 in the Premier League's latest round of testing.
Between Monday 6 December and Sunday 12 December 3,805 players and club staff were tested for the virus.
This represents a sharp rise from the 12 detected in the previous round.
A statement from the Premier League on Monday said;
"COVID-19 Emergency Measures, which are applicable to all clubs, include protocols such as wearing face coverings while indoors, observing social distancing and limiting treatment time. These are in addition to the more frequent testing.
"We will continue to work closely with the Government, local authorities and supporter groups while being responsive to any future changes to national or local guidance.
"The Premier League is providing this aggregated information for the purposes of competition integrity and transparency.
"No specific details as to clubs or individuals will be provided by the League and results will be made public on a weekly basis."
Significant spike in coronavirus cases in the Premier League - 42 positives over the last week among players & club staff after 12 were reported the previous week pic.twitter.com/X9uqPdQC3M
— Rob Harris (@RobHarris) December 13, 2021
News of the rise in cases come on the same day Manchester United shut down their Carrington training base for 24 hours after a number of positive cases among players and staff.
Their game against Brentford on Tuesday night is now in doubt.
A club statement on the matter said;
"Manchester United can confirm that following PCR test confirmation of yesterday’s positive LFT Covid-19 cases among the first team staff and players, the decision has been taken to close down first team operations at the Carrington Training Complex for 24 hours, to minimise risk of any further infection.
"Individuals who tested positive are isolating per Premier League protocols.
"Given cancellation of training and disruption to the squad, and with the health of players and staff the priority, the Club is in discussion with the Premier League whether it is safe for Tuesday’s fixture against Brentford to continue, both from a Covid infection and player preparation perspective."
As well as this, this past weekend saw Tottenham Hotspur's game with Brighton postponed on account of a COVID-19 outbreak at Spurs.