A Wellington teacher is believed to be the first New Zealander to have contracted a superbug resistant to every antibiotic.
Brian Pool died in July from complications caused by a stroke, but doctors say his immune system was weakened from fighting the bacteria, Fairfax reported.
It was believed the 68-year-old picked up the bug while travelling overseas.
In January, while he was teaching English in Vietnam, Mr Pool suffered a brain haemorrhage and was operated on in a Vietnamese hospital.
He was flown to Wellington Hospital where tests found he was carrying the strain of bacterium known as KPC-Oxa 48 - an organism that rejects every kind of antibiotic.
Wellington Hospital clinical microbiologist Mark Jones told Fairfax: "Nothing would touch it. Absolutely nothing.
"It's the first one that we've ever seen that is resistant to every single antibiotic known.
"This man was in the post-antibiotic era, and this is why so many agencies over the world are raising alarm bells."
After the diagnosis, Mr Pool spent that last six months of his life in quarantine unable to leave his room.
His twin sister Maureen Dunn said they were not even able to take him outside.
"He just wanted to get out in the sun, and we couldn't take him out."
Ms Dunn said the family was frightened, and even doctors did not seem to know how the bug would affect others.
"They were s**t scared, to put it bluntly, in case these bugs were transferred to another patient or taken out into the community."
Earlier this year, British chief medical officer Sally Davies described resistance to antibiotics as a "catastrophic global threat" that should be ranked alongside terrorism.
Wellington Hospital infectious disease physician Michelle Balm said Mr Pool's superbug could have been contracted when he was in hospital in Vietnam, or a few years earlier when he had hernia surgery in India.