Because of level 4 lockdown conditions, the woman's family wasn't able to visit her or be with her before she died in hospital.
The family would take time to grieve and the Ministry of Health's thoughts were with the family, McElnay said.
She couldn't say how many people at the rest home had been tested but said investigations were under way to find out how Covid-19 got into the rest home.
The ministry said some people displaying symptoms at the rest home hadn't been tested because of their particular vulnerabilities and the distress it would cause them, but they were being treated as probable cases.
The Covid-19 test wasn't particularly distressing for most people, but for some of the group at Rosewood it was difficult for nurses to explain what was happening and why they needed to be tested, McElnay said.
The CDHB would be able to provide more information this afternoon about the other Rosewood residents who had been hospitalised.
Fourteen of the new cases announced today are linked to existing clusters. In total, 373 people have recovered - an increase of 56 on yesterday.
The total number of cases in New Zealand is 1283.
There are 16 people in hospital. Four are in ICU, Wellington, Waitemata, Waikato and Southern - two of whom are in a critical condition.
McElnay said she recognised the challenge religious leaders faced this Easter but urged them to follow the Prime Minister's advice to stay home and organise to worship from there.
Prime Minister Jacinda Ardern yesterday said the sacrifices Kiwis had made in the past two weeks to try to break the chain of Covid 19 were "huge".
"In the face of the greatest threat to human health we have seen in over a century, Kiwis have quietly and collectively implemented a nationwide wall of defence.
"We are turning a corner. But to succeed, we need it to keep working."
She said to expect roadblocks this Easter weekend.