Charlie Dean and Maia Bouchier have been ruled out of England's opening T20I against New Zealand after being identified as possible contacts of a COVID-19 case.
The pair, who both earned maiden international call-ups for the series, are expected to join up with the England squad ahead of the second T20I at Hove in a week's time, pending test results.
"In order to evaluate the situation and undergo further testing they will miss the first Vitality IT20 against New Zealand," the ECB said.
Emma Lamb has been drafted into the England squad ahead of the first match, at Chelmsford on Wednesday.
Batting allrounder Lamb scored an unbeaten 111 off 61 balls opening for Thunder in the Charlotte Edwards Cup against Sunrisers in July, when she also took 3 for 16. She then played all seven of Manchester Originals' completed matches in the Hundred, with notable scores of 32, 39 and 46 and claiming all three of her wickets for the tournament against Birmingham Phoenix, again taking 3 for 16.
The as-yet uncapped Lamb was named in a 24-strong England training squad last June as players resumed individual programmes at various venues around the country after the first wave of the Covid pandemic.
Lamb's inclusion means that England have again resisted the temptation to pick 17-year-old allrounder Alice Capsey despite her impressive efforts for Oval Invincibles during their late charge to the Hundred title.
Bouchier scored 92 runs in seven innings for Southern Brave during the Hundred at an average of 30.66 and with a strike rate of 143.75. Allrounder Dean, who played for London Spirit in the Hundred, claimed a wicket and scored 22 as part of an England A team which beat New Zealand by four wickets in a 50-over warm-up match.
Taunton will host the last of the three England-New Zealand T20Is on September 9, with five ODI matches to follow as both sides ramp up their preparations for the World Cup, starting in New Zealand in March, where England are defending champions.