England head into the third Test at Headingley on Thursday with doubts over the health of captain Ben Stokes as they chase a 3-0 series clean sweep against New Zealand.
Stokes missed training on Tuesday through illness, with a team spokesman saying the all-rounder tested negative for the coronavirus and was being kept away from the squad as a precautionary measure.
New Zealand have had several positive cases in their squad during the tour, with Black Caps skipper Kane Williamson ruled out of the second Test.
As well as Williamson, the tourists have also seen Henry Nicholls, Devon Conway, Michael Bracewell and two members of their backroom team return positive results in England.
All four players are fit and available to play in Leeds this week.
England have yet to name a vice-captain since Stokes’ appointment.
If he is unavailable, Stokes’ predecessor Joe Root could resume captaincy duties, although the way he has spoken of the mental toll leadership took on him may mean he is reluctant to take charge again, even on a temporary basis.
That would leave England facing a tricky decision if they want to make a senior figure such as James Anderson or Stuart Broad the stand-in captain at Headingley.
With England having already won the New Zealand series, the hosts may be tempted to rest at least one or other of their two all-time leading wicket-takers.
England face a re-arranged finale to last year's Covid-postponed Test series against India, starting at Edgbaston on July 1.
They do have additional pace-bowling options in Craig Overton and uncapped twin brother Jamie, who has been added to the squad.
No twins have yet played in the same England XI, with Jamie Overton saying: “It would feel pretty special. It's a moment that we’ve always wanted.”