The fiancée of a 26-year-old man who the Ministry of Health has confirmed probably died from the Pfizer COVID-19 vaccine says the risks and symptoms of myocarditis aren't clear enough.
Ashleigh Wilson says if Rory Nairn had known more about them, he might still be alive.
Wilson and Nairn had just bought their dream home and were busy planning their summer wedding.
"We did have lots of future plans," she told Newshub. "It was all just starting to happen for us.
"He just loved life, he enjoyed every moment of it."
But last month, Nairn collapsed and died from myocarditis - 12 days after receiving his first Pfizer vaccine dose.
The Ministry of Health has confirmed it is probable he died because of the vaccine.
"He really didn't want to get the vaccine so it was really upsetting that it is what killed him but also we were just really relieved to get an answer as we knew in our hearts that was what happened," Wilson said.
Myocarditis is an inflammation of the heart muscle that is treatable if caught early.
Nairn experienced symptoms but Wilson said they had no idea of the risk. She found he'd been searching it on his phone before he died.
"One of my main concerns is the use of the words 'rare' and 'mild,'" Wilson said. "I've had a massive influx of messages globally who are having heart problems."
Health officials on Tuesday extended their sympathies, with Ministry of Health chief science advisor Ian Town saying he was "deeply saddened with that report".
But the ministry insisted myocarditis was a rare side effect of the vaccine.
"Although this particular case was probably associated with the vaccination, it is extremely rare internationally," Dr Town said.
It is also a known complication of COVID-19 itself.
"[People are] somewhere between five and 10 times greater chance in getting myocarditis from COVID than it is from getting myocarditis from the vaccine," said John Tait of the COVID-19 vaccine independent safety monitoring board.
About 230 cases of myocarditis have been reported to the board following the Pfizer vaccine - most are mild reactions and two people have died in New Zealand.
"Remember that's two out of over 8 million doses," Dr Tait told Newshub. "It is a safe and very important vaccine to take."
But Wilson said if side effects and warnings had been made clearer, Nairn would have known to seek help.
"It is important that if you've had your vaccine and you develop any symptoms that you're uncertain of but particularly if you get palpitations, chest pain or shortness of breath, you should contact a health professional," Dr Tait said.
But Wilson said that advice wasn't clear enough - and hoped Nairn's story can help others.
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