Hawke's Bay DHB has raised concerns about a Covid-19 anti-vax contractor.
Dr Elena Bishop, an anatomical pathologist, works for Southern Community Laboratories onsite at Hawke's Bay Hospital.
She has called the Pfizer vaccine "a crime against humanity" in an online video, saying the government, doctors, nurses are "implicated" and the media also "will be punished".
"We have to stop this before it's too late."
Southern Community Laboratories chief executive Peter Gootjes would not comment to RNZ about his staff member's statements.
But in a statement to RNZ, the Hawke's Bay DHB said it had contacted Peter Gootjes about Bishop, "and raised concerns that her practice may not be in line with Medical Council requirements".
"The DHB has further concerns, regarding her position, following the government announcement that vaccination will be a mandatory requirement for healthcare workers from 1 December."
Five thousand doctors from around Aotearoa have signed a letter supporting the Covid-19 vaccine rollout.
But Dr Bishop is one of a handful of doctors who have pushed Covid-19 anti-vax views in online videos.
This week, the Royal College of GPs also confirmed to RNZ that complaints had been made to the Medical Council about a Blenheim GP Dr Deon Claassens.
He put out a 25-minute video advocating for the use of ivermectin and hydroxychloroquine to treat Covid when he stood for One Party in last year's general election.
The college says the use of ivermectin is "strongly not recommended".
And Pharmac has made it clear that "hydroxychloroquine has not demonstrated an overall benefit in the treatment of Covid-19".
Dr Claassens would not comment to RNZ, but in his video, he said "we need to change" the rules "so the doctor can decide what's best for his patient, not the government".
Royal College of GPs president Dr Samantha Murton has seen a snippet of the video.
She was reassured the Medical Council was aware of it.
"Anything that we've had that's come up that is misinformation, so, leading people in the wrong direction as far as treatments to Covid or other vaccination information that's not accurate, then, notifying the Medical Council that those things are around is really important."
Meanwhile, a Murupara GP is awaiting the outcome of a Medical Council hearing, after allegedly questioning the rollout of the vaccine to youth and pregnant women.
Dr Bernard Conlon's clinic is not offering Covid-19 vaccinations in the small Bay of Plenty, which still has the lowest uptake in the country, despite a visit from the prime minister last week to promote the rollout.