Arlott, who has yet to make her international debut, has returned home to recover and has been replaced by Issy Wong
Emily Arlott has dropped out of the England squad for the upcoming Test against South Africa.
The seamer was part of a 13-strong group picked for the clash in Taunton, but is suffering from the after-effects of Covid-19 and has left the camp two days before the scheduled start.
Arlott, who has yet to make her international debut, has returned home to recover and has been replaced by Issy Wong.
Central Sparks quick Wong was already with the squad in the south west as a travelling reserve.
The game is scheduled to get under way at the County Ground on Monday.
Issy Wong replaces Emily Arlott in the England squad [Getty Images]
England last won a Test in 2014, but gave Australia a run for their money in the red-ball element of the last Ashes series over the winter.
"We found ourselves in slightly different situations but I thought the way we approached that game in Canberra is exactly how I want us to approach the game we've got next week," captain Heather Knight said.
"I want us as batters and bowlers to try and take the game forward at any opportunity we've got. The way we nearly chased down that total in Canberra was brilliant.
"Obviously it didn't quite end how we wanted it to but if we can take the game forward as much as we can, give the team the best chance to try and win that match, that's going to stand us in good stead to hopefully win a Test match because obviously the last few have been draws and we've spoken about it this week ,that next week is a really good opportunity for us as a side to actually win that Test match."
England squad: Heather Knight (c), Tammy Beaumont, Lauren Bell, Kate Cross, Alice Davidson-Richards, Freya Davies, Charlie Dean, Sophia Dunkley, Sophie Ecclestone, Amy Jones, Emma Lamb, Nat Sciver, Issy Wong