Cause of illness a mystery
It could have been an unsterilised tattoo needle or the blood transfusion he had after a car accident that left Glenn Macrae with hepatitis C.
The Titirangi man is cured after a lengthy run of medication trials but still no closer to finding out the exact cause.
Macrae first learnt he had contracted hepatitis C in 1979 when a blood test indicated a positive virus strain.
"Back then they hadn't identified the C strain and because the virus I had wasn't A or B, the doctor sent me home and said I'd be OK in six months time," the 62-year-old says.
"I never gave it another thought."
But the disease - known as the silent killer - slowly attacked his system over the next 30 years.
It was detected again during a routine checkup when Macrae turned 50.
"They call it the silent killer because you don't know you've got it until it's too late," the father-of-two says.
"It manifests and eats away at your liver until it's destroyed."
A biopsy revealed Macrae had mild fibrosis, or fibre in the liver.
He underwent years of different drug trials in an attempt to drive the virus away.
The gruelling regimen of medication resulted in a heart attack and Macrae developed depression as his body was pumped full of multiple drugs.
"At one point I was taking up to 30 pills a day and ended up like a pin cushion from all the needles.
"Having hepatitis was like living with a death sentence and I didn't have a good outlook on life.
"I was at the bottom of a pit and I couldn't see a way out of it," he says.
Multiple drug trials failed to reduce the viral count.
Doctors started scanning Macrae's liver for cancer as his fibrosis worsened.
It was the third drug trial that reduced the virus dramatically.
He's been free of the disease for more than a year.
It's been a life-changing journey, he says.
"I've realised life is so precious and it hasn't been easy but it was bloody worth it to be hepatitis C free."