"Player welfare is paramount, particularly in today's environment," he said. "It's important to respect the needs of the athletes.
"Amelia has shown a lot of courage in making this decision and I look forward to her return to the White Ferns when the time is right."
Captain Sophie Devine was philosophical about Kerr's absence from the UK tour.
"We're obviously going to miss Melie in England," said Devine.
"As a cricketer she offers plenty in all three aspects of the game and is great fun to have around off the park.
"Every individual knows how tough the environment is at the moment with Covid-19; time away from family, living in a bio-bubble or quarantine periods.
"We're really fortunate we have great support around us from both New Zealand Cricket and the CPA.
"It's important we talk openly about it because it can get tough and we need to ensure our players, teammates and friends are looked after. We're all wrapping around Melie and know she'll make a comeback when she's ready."
Wellington Blaze wicket-keeper Jess McFadyen and Central Districts seamer Claudia Green have earned their maiden call-ups to the squad.
Carter said he was delighted for the two new players in the squad.
Green caught the selectors' eyes last summer when she took five for 48 for the New Zealand XI against England in a Queenstown warm-up fixture.
McFadyen received her maiden White Ferns contract for the 2021-22 season after impressive domestic form for the Wellington Blaze. She tours as a second wicket-keeping option alongside Katey Martin.
"This is a really exciting time for both Jess and Claudia," said Carter.
"Both have impressed at domestic cricket and thoroughly deserve their chance at the next level.
"Jess has an outstanding work ethic and we want cricketers who are determined and willing to work hard. If she gets her chance over in England I know she'll be ready.
"Claudia showed what she can do against England last summer for the New Zealand XI against a quality English batting lineup.
"She swings the ball and can cause trouble at the top of an innings. This tour represents a chance to work on her game and experience new conditions, and I know she'll be pushing hard for a spot in the eleven."
The White Ferns depart for the UK on Friday August 13 with the first T20I against England on September 2 at County Ground, Chelmsford.
White Ferns touring squad for England
Sophie Devine (c) (Wellington Blaze)
Amy Satterthwaite (vc) (Canterbury Magicians)
Suzie Bates (Otago Sparks)
Lauren Down (Auckland Hearts)
Claudia Green* (Central Districts Hinds)
Maddy Green (Wellington Blaze)
Brooke Halliday (Northern Districts Spirit)
Hayley Jensen (Otago Sparks)
Jess Kerr (Wellington Blaze)
Katey Martin (wk) (Otago Sparks)
Leigh Kasperek (Wellington Blaze)
Rosemary Mair (Central Districts Hinds)
Jess McFadyen* (wk) (Wellington Blaze)
Thamsyn Newton (Wellington Blaze)
Hannah Rowe (Central Districts Hinds)
Lea Tahuhu (Canterbury Magicians)
*potential debutante