SA-W in ENG (1)
IRE v IND (1)
WI v BDESH (1)
ENG v NZ (1)
County DIV1 (4)
County DIV2 (3)
Down had injured her right thumb while taking Shafali Verma's catch during the fifth ODI against India. Subsequent scans revealed a fracture.
"Quite simply, the entire squad is absolutely gutted for Lauren." New Zealand head coach Bob Carter said. "She's a very popular member of the group and it's fair to say the team were quite emotional when we got the news she was out of the tournament."
Down has played 22 ODIs, scoring 352 runs at an average of 17.60. She was in good touch during the India series and was named Player of the Match for her unbeaten 64 off just 52 balls, which helped New Zealand chase down 280 in the third ODI.
"You saw the impact Lauren had in the recent series against India; she played some really mature innings in the middle order and her fielding was at an exceptional standard," Carter said.
Plimmer, 18, is yet to represent New Zealand in any format. In the ongoing domestic one-day competition, playing for Wellington, she has scored 95 runs in four innings at an average of 23.75.
Auckland seamer Molly Penfold will also join the side as a travelling reserve. Both Plimmer and Penfold will undergo the necessary five-day "bridging in" isolation period before officially joining the squad.
The New Zealand team arrived in Christchurch on Friday in preparation for their warm-up matches on February 27 and March 1 against Pakistan and Australia respectively.