“As far as I’m aware, a few guys are not feeling 100%,” Root told a news conference. “I didn’t feel great yesterday and I woke up a lot better today. So hopefully it’s a 24-hour virus.

“Don’t think it’s like food poisoning or COVID or anything like that. I think it’s one of those things which we unfortunately picked up as a group.

First Test between Pakistan, England may face delay

“We are trying to do absolutely everything right to make sure we are prepared for this game.”

England have already named their starting 11, giving a Test debut to Liam Livingstone and recalling Ben Duckett to open with Zak Crawley.

They are scheduled to play in Rawalpindi, Multan and Karachi in their first test tour of Pakistan since 2005.

They have hired a chef for the tour after receiving feedback from players who visited Pakistan in September-October for a seven-match T20 series.