With the Omicron coronavirus variant spreading rapidly around the country, speculation has been mounting over how football will respond to the threat of the virus being transmitted in stadiums and among players.
After recent Premier League fixtures have been dramatically cancelled or postponed following positive tests, football bosses have expressed concerns about what effects the spread could have on the upcoming match schedule.
Along with the rest of the nation, there is likely to be a renewed push for double-jabbed players to receive their booster in the coming weeks to limit the chances of outbreaks.
So how likely is it that coronavirus could see matches postponed in the UK and what could this mean for fans?
Why are there fears the football Christmas season could be disrupted this year?
Six Premier League games were postponed last season.
Lower divisions, including League One sides such as Ipswich Town, also had to call off games after positive coronavirus tests last December.
The Omicron variant, expected shortly to become the dominant strain around the country, is thought to be more transmissible then previous ones - so could spread more easily among the public.
In October, the Premier League said that some 68% of players had been fully vaccinated, with 81% receiving their first dose.
This means that almost a third of players are likely to have to wait until at least the end of January to receive their booster, as a significant number of second doses were not administered until October.
What Premier League fixtures have already been cancelled over Covid?
On Monday, Arsenal became the latest club to reintroduce measures to combat the spread of Covid-19, after a small number of training ground staff reportedly tested positive for the virus.
Coronavirus had already impacted Arsenal this season after four players tested positive on the eve of their opening day clash with Brentford, which they lost 2-0, in late August.
In another stroke of bad luck, Brentford's Premier League clash on Tuesday night with Manchester United had been postponed due to a Covid-19 outbreak at the Old Trafford club.
Manchester United defender Victor Lindelof is said to have recovered well from the breathing difficulties suffered during the team's earlier win over Norwich City, with the issue not linked to the club’s outbreak.
Brighton, Tottenham, Leicester, Manchester United, Aston Villa and Norwich have all confirmed cases, with Sunday's Brighton v Tottenham fixture postponed following a Covid-19 outbreak at Spurs.
What managers have expressed concern about disruption to the footballing schedule?
David Moyes said the Covid outbreak affecting Tottenham shows the wider risk in football.
"Covid doesn't pick and choose who it's going to jump on. If you get it then we just have to find a way of getting rid of it quickly," he said.
"It's affecting the game we work in. We're getting games called off now so I think we'd all really like for it to go away, but it's not so we have to deal with it the best we can."
Tottenham boss Antonio Conte, meanwhile, has admitted he had been "scared" by the outbreak at the north London club, which also caused the team's European fixture against Rennes last week to be called off.
Eight players and five members of Spurs' staff had tested positive.
“Everyone is a bit scared because we have family and [we ask]: ‘Why I have to take this risk? Why?’ This is my question. Tomorrow, who [will be positive]? Me? I don’t know. Maybe," Conte told a press conference, which had to be staged remotely.
"Better me than a player for sure but I think that it is not right for everyone because we have family and contact with them when we come back home.
"Football is the most important thing but today to speak about football is impossible. There are situations that made me very upset.”
How are football fans in England affected by the new coronavirus rules?
In order to attend a Premier League game from December 15, fans will be required to show proof of double vaccination via the NHS Covid app, or proof of a negative lateral flow test taken inside the previous two days.
This doesn't only apply to football - it is a requirement mandated by the government to attend any sporting event in England with crowds of more than 10,000 people.
Speaking after Boris Johnson's press conference last week, West Ham boss David Moyes suggested it was time for English football to bring in vaccine passports and only allow fans into grounds if they have been jabbed.
Moyes said: “I do feel that I think we're getting to a stage now where, you know, we don't want any more Covid. There's been too many deaths throughout the world. “I think we need to try and make sure we try and eliminate it the best we can."
The new rules will likely trigger chaos for fans entering stadiums, where they have largely only been spot-checked for their vaccine status in the first months of the season since grounds reopened. Fans have been able to attend matches in big numbers without wearing face coverings or having their vaccine status checked during this season.
Scientists have urged against people gathering in large crowds to help limit the spread of the virus.
What is the situation like in other European countries?
Several European countries have responded to the rise in cases by bringing in measures to limit the potential spread of the virus.
In Germany, for example, Bundesliga matches can only have an attendance of up to 50% and a maximum of 15,000 after the country reintroduced restrictions in December.
Measures include reducing fans at outdoor and indoor sports events - a big change as German stadiums had been operating at near-full capacity this season.
In November, football behind closed doors made a comeback in the Netherlands after the government ordered a partial lockdown in response to a rise in Covid cases.
The Netherlands' World Cup qualifier against Norway in Rotterdam’s De Kuip stadium was the first match to be affected.
How have managers responded to mounting coronavirus fears?
Several Premier League managers are urging players to get vaccinated against Covid-19.
Manchester City manager Pep Guardiola suggested he would encourage his players to have the booster in order to offer greater protection against the virus.
"The doctors suggest that they have to do it. Most of us have [had] it already. The players, for their age, the moment they have to do it, everybody is going to decide and they are going to do it," he said.
Fellow managers Mikel Arteta, Nuno Espirito Santo, Steve Bruce and Graham Potter have also urged players to get jabbed.
Aston Villa manager Steven Gerrard said that, with most of his team being double-vaccinated, vaccinations would be discussed with any transfer targets in January.
“We’re very thorough and detailed in terms of our recruitment process... We look at everything, so I’m sure it’ll come up," the former England star said.
“It would certainly come into conversations in the background."
How many Premier League players have tested positive for coronavirus?
The Premier League announced on Monday that a record 42 players and staff tested positive for Covid in the previous week, the highest number since 40 cases were reported in January.
The latest report of 42 results is a rise of 30 on the 12 positives reported from 3,154 tests between November 29-December 5.
Previously, the most positive tests recorded in a week this season was 16 - from 16-22 August, when there were 3,060 tests carried out.
What has the Premier League advised clubs to do to prevent virus outbreaks?
Last week, the Premier League advised its 20 clubs to return to emergency measures, as Boris Johnson's Plan B Covid measures were announced for England. The protocols, which include social distancing and wearing masks in indoor areas, were brought in at the start of the season.
"With the health of players and staff the priority, and in light of the recent rise in Covid-19 cases across the country, the Premier League has reintroduced emergency measures," the Premier League reiterated in a statement late Monday.
Some clubs with high vaccination rates had eased some of the measures but must now reimpose restrictions to help limit the rapid spread of the Omicron variant.
There are 4,713 confirmed cases of the Omicron variant but Health Secretary Sajid Javid said the UK Health Security Agency estimated the current number of daily infections was around 200,000.
The Football Supporters Association has backed the vaccine passport proposals, in the hope of avoiding a return to sport behind closed doors.
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