The death of a Dunedin man is being investigated by health officials and the coroner to ascertain whether it could be connected to the Covid vaccine he received 12 days earlier.

Rory James Nairn, 26, died on November 17 at the home he shared with his fiancee Ashleigh Wilson.

His death has been referred to the coroner and the exact cause is yet to be determined.

Nairn received his first dose of the Pfizer Covid-19 vaccine on November 5.

Health officials are also aware of Nairn's death but cannot comment because of the coronial investigation.

Wilson said it was frustrating not to have any clear answers and she decided to share Nairn's story.

She said whether his death was vaccine-related or not, he should been made more aware of potential side effects.

If he had, he may have sought medical help sooner.

Instead, he shrugged off his ongoing symptoms, which Wilson said he did not have before his first dose of the vaccine, and put it down to stress.

Wilson said Nairn, a plumber, "started feeling heart flutters" a few hours after his jab.

"We put this down to stress as we were in the process of selling and buying a house and planning a wedding," she said.

"We never, ever considered the events that followed.

"Rory had heart palpitations regularly at night, and again, we thought this was stress.

"Twelve days later, Rory was up and down again during the night with his heart palpitations and an 'uncomfortable' feeling in his chest."

At 3am on November 17 the couple decided to go to the hospital for "reassurance".

But within minutes Nairn collapsed.

"It was really, really traumatic," Wilson recalled.

"I watched him die and I could not get to him. We were about to leave for hospital and he was in the toilet and I heard a thud.

"He had fallen, his body was blocking the door, his full weight was against it and I couldn't get it open.

"I could just see him through a crack in the door, I could see that he was gone."

Wilson called 111 and paramedics tried for 40 minutes to resuscitate him but he was pronounced dead.

She believes his death may have been an adverse cardiac event as a result of the vaccine.

However no one can give her any solid answers.

Rory James Nairn was 26 when he died. Photo / Supplied

A spokesperson from coroner Sue Johnson said Nairn's case was "active".

"The causes and circumstances of death have yet to be determined," said the spokesperson.

Ministry of Health Covid-19 Vaccine and Immunisation Programme national director Jo Gibbs confirmed the Centre for Adverse Reactions Monitoring had also been informed.

"The report was made because they had previously received their Covid-19 vaccination," Gibbs told the Herald.

"For privacy reasons, we cannot confirm any details of the deceased person. Their death has been referred to the Coroner's Court, so we are unable to comment."

Gibbs' said Nairn's death was "incredibly sad" and the ministry's thoughts went out to his family and friends.

Wilson agreed to speak to the Herald about the tragedy two weeks to the day after Nairn died.

She hoped sharing his story would spark more awareness around the vaccine, what people should watch out for in terms of side effects and when they should seek medical help.

She felt not enough information was made public about adverse reactions and that meant people like Nairn were too casual about what they were experiencing and were more likely to ignore symptoms than seek help.

Wilson herself is double vaccinated.

She appreciated the Government and public health agencies did not want to "scare" people off getting the vaccine - but said people had a right to know everything about it, and what it could do.

She also hoped speaking out might help her get answers about her partner's death faster.

The coronial process can take months or years and she was desperate to know as soon as possible why the love of her life died.

"My main fight is just to find out why," she told the Herald.

Rory and his fiance Ashleigh Wilson were set to move into their dream home, get married and try for a baby. Photo / Supplied

"And to bring more awareness… maybe if there was more information about possible side effects and when people should go to hospital Rory would still be here now."

She acknowledged the official health websites had information about the vaccine including side effects, and that people are given a pamphlet to take away after their jab.

But she felt the heart-related symptoms were "downplayed" in the literature and the messaging needed to be clearer and more widely spread.

"It's all a bit blase. Yes, you get that little pamphlet, but you just don't hear about any adverse cases," Wilson said.

"Rory wasn't worried about his symptoms until that night. But if you have symptoms to do with your heart you really need to get to hospital to get answers."

Wilson hoped people would take their health more seriously after reading Nairn's story.

"It's been two weeks. It's been really rough," she said.

"But I've just switched into fight mode - it's giving me a bit of a purpose.

"Rory was a really typical Kiwi bloke - he never complained and he was always happy and humble.

"He was an amazing guy who lit up the room, he had one of those laughs that got everyone else laughing.

"He was lovely."

The couple met at high school and were an item for two years when they were 14.

They broke up but reunited six years ago and were due to get married on March 26.

They had just bought their dream home by the beach and were planning to start trying for a baby straight after their wedding.

"It was all about to start for us," said a shattered Wilson.

"He had his whole life ahead of him.

"I urge anyone who experiences any heart symptoms post-vaccination to seek medical advice at a hospital immediately."

Nairn's funeral was held on November 25.

He is survived by his parents and siblings.

FOR INFORMATION ABOUT THE COVID-19 VACCINE CLICK HERE.