Moeen Ali has tested positive for Covid-19 on arrival in Sri Lanka.
England's touring party landed in Sri Lanka on Sunday, January 3 ahead of their two-Test series and were tested on arrival. Although the ECB initially reported that all results were negative, it has subsequently transpired that while Ali's lateral flow test - the quicker version of the test which takes only 30-minutes or so to complete - was negative, the more accurate PCR test, which takes longer to analyse and was also carried out at the airport, was positive.
The ECB have also confirmed the result is not a false positive, though Ali is understood to be asymptomatic at this stage.
He will be required to undergo a 10-day period of self-isolation, in line with the Sri Lankan government's quarantine protocols. England are currently staying in Hambantota, but are due to move to Galle on January 10 ahead of the first Test. Ali will be driven to new accommodation, a private hotel not in use by the rest of the team, in Galle on Tuesday January 5.
An ECB spokesperson said that it was "too early to confirm" whether Ali could play in the first Test, which starts on January 14, but with his self-isolation ending the day before, it appears certain that he will miss it. He was England's joint highest wicket-taker (with Jack Leach) on their previous Test tour of the country in 2018.
Chris Woakes has also entered self-isolation after being deemed a close contact. An ECB statement said that Woakes "will observe a period of self-isolation and further testing". It is understood that isolation period will last for seven days from the date of the positive test on Sunday.
England had been due to start training on Tuesday afternoon after another round of tests in the morning, but are now due to train for the first time on Wednesday instead. Further testing will take place on Tuesday and Thursday.
The tour party have been in quarantine in individual hotel rooms since they arrived and observed social distancing protocols on the journey.
The news comes three days after Joe Root, England's captain, said that a positive test would not necessarily put an end to the tour, instead suggesting that the squad would have to "manage it as [well] as possible". England's last two overseas tours - to Sri Lanka in March 2020, and South Africa in December - have been abandoned early due to concerns about the virus.
"They are decisions that have to be made by the medical staff and the people entrusted in making those decisions. I don't think it's a player decision, even though guys have the opportunity to opt out if they don't feel safe," Root said.
Ali was, alongside Dom Bess and Leach, one of three front line spinners in the main Test squad. There are, however, three more (Mason Crane, Matt Parkinson and Amar Virdi) among the players on standby. England included three spinners in the team that won in 2018.
The timing, from a personal perspective, is far from ideal. This tour was seen as something of a crossroads for Ali, with a chance to reestablish himself in the longest format and a possibility that England might move on from him if he was unable to do so. He has not played a Test since August 2019.
Ali's cousin, the former England swing bowler Kabir Ali, was also diagnosed with Covid a few weeks ago and was obliged to pull out of a stint coaching in the LPL as a result. He has subsequently made a full recovery.
It is not clear at this stage what strain of the virus Ali has. The UK has recently been hit by a new strain which is understood to be up to 70 per-cent more transmissible than the previous version and has seen positive cases running at more than 50,000 a day over much of the last week.
Should this prove to be the new strain, there is sure to be increased doubt over the wisdom of people travelling from the UK for any reason. That could have an impact on the plans for not only this tour, but the tour to India that follows.
George Dobell is a senior correspondent at ESPNcricinfo