New National leader Judith Collins has stripped Michael Woodhouse of his health portfolio and given him a public dressing down for the errors he made regarding leaked Covid-19 patient information.

She gave Shane Reti – Whangarei MP and medical doctor – that portfolio and promoted him to National's front bench.

Speaking to media after a caucus meeting today, Collins said Reti was a "top performer" and was up to the challenge.

Late on Tuesday night, Collins was elected as National's leader after Todd Muller's shock resignation earlier that day.

Gerry Brownlee was elected as her deputy.

The promotion of Reti was the most significant portfolio change she announced today – more details of her reshuffle will be announced today.

Woodhouse's demotion was squarely down to his involvement in leaked Covid-19 patient information.

Woodhouse received similar information to now-disgraced MP Hamish Walker, who leaked the information to media.

Woodhouse did not leak the sensitive material – but Collins pointed out that he did not make it known to the Minister of Health as soon as he got it either.

"I feel the right thing for him to have done would have been to advise her [Michelle Boag] to not send him anything."

Boag – former National president – confessed to being Walker's leak and resigned her membership of the party soon after her admission.

That was his error, Collins said, before adding that the public was "rightly appalled" by the leak.

She said she has talked to Woodhouse about the issue and he accepts his error.

But she said it was time to move on – "I have no doubt Michael [Woodhouse] will not make that mistake again".

In fact, she said none of her MPs will make that sort of error in the future.

"The matter has now been resolved," she said. "I think we need to move on."

Reti – who is of Māori descent – promotion to the front bench comes after National faced considerable amounts of pressure for the lack of racial diversity on its front bench.

Asked if Reti's promotion would help ease some of this pressure, Collins said: "Do you know what? I hope that Shane Reti's promotion is going to start the discussions about the fabulously talent we have in the National Party."

Although he loses health, Woodhouse picks up the Pike River recovery and regional economic development portfolios.

Collins has "huge confidence" in the Dunedin MP and said he was "utterly delighted" in his new roles.

As for herself; Collins will pick up national security – a portfolio traditionally held by the leader of the opposition.

Her only other responsibilities, she said, was being National's leader.

This means her current portfolio allocations – economic development, regional development and Shadow Attorney General – will all need to be reallocated.