(file image) Photo: RNZ / Marika Khabazi
Correction: The survey results included in this story have been clarified.
A retired public health medicine specialist says there could be hundreds of people living in severe squalor across the country.
It comes as a preliminary survey of Age Concern and territorial authorities suggest from their work that many of their clients live in these circumstances.
Thirteen out of 31 Age Concern organisations (42 percent) completed the survey - and nearly all (92 percent) of those surveyed said they had been involved with clients with severe domestic squalor in the past 12 months.
Of 15 out of 67 territorial authorities (22 percent) surveyed, nearly all (93 percent) said they were involved with people living in severe domestic squalor.
Dr Jonathan Jarman, who led the research, said the average age for those living in these conditions was 65. The figures included some who were older.
In one part of the country, which Jarman would not reveal, two agencies had a total of 46 clients living in severe domestic squalor, he said.
Jarman defined these conditions as infested by vermin, cluttered in rubbish, with decomposing food and stench.
"We're talking quite extreme conditions, it's not just a messy house, this is something that most people would say was so, so dirty and messy and unhygienic that it wasn't fit for human occupation."
Eighteen people living in severe domestic squalor referred to the Public Health Service in Taranaki between 2014 and 2016 had a median age of 65, with the youngest person being four and the oldest 97.
Dr Jonathan Jarman led the research. Photo: RNZ / Robin Martin
Several triggers could contribute to someone living in severe squalor, which often included mental health issues, but they were not severe enough to require compulsory treatment, he said.
"There might be a stroke, or there might be worsening arthritis, or the husband or wife might have died and the person's by themselves, they can be psychiatric conditions, or they can be really nothing you can put your finger on."
Living in these conditions was also damaging to a person's health.
"They are often frequent fliers for the health service, so they're in and out of hospital for a whole variety of reasons" Jarman said.
"If they have a wound that doesn't heal well, they have medical conditions which are not looked after well, there's a personal risk of a fire. The conditions are so bad in the home that carers refuse to go in because of health and safety.
Karen Billings-Jensen. Photo: Mike Clare / supplied
"They're by themselves, they could actually die at home and no one would discover them for a couple of weeks. So that's called a lonely death."
Australian research indicated the number of people living in severe domestic squalor in New Zealand could be up to 2000 homes in the country, he said.
"Agencies such as Age Concern and territorial authorities are soldiering away on it by themselves and clocking up a lot of staff time, when it would be so much easier if we could have a multi-agency approach throughout New Zealand with some expertise, and then we can start using international best practice."
"It's often behaviours that exist through the life course" - Age Concern chief executive Karen Billings-Jensen
Age Concern chief executive Karen Billings-Jensen told Morning Report the full extent of the problem remained unknown.
"But certainly from what was pulled together by Dr Jarman and a couple of the Age Concern people was some indicative numbers - around four in 100,000, which would show some quite reasonable numbers across New Zealand affecting individuals and communities."
She said many subjects were living alone, disconnected from their neighbours, perhaps without family or friends. "A large portion" owned their own homes, so would never have a landlord or property manager around to check in on the state of their place.
"It's often behaviours that exist through the life course. So while obviously Age Concern are involved, it's not a problem that is only for older people. I guess it's just that if they've had hoarding behaviours or some patterns of living that may not come to a head until they're older.
"But we do know that it is probably behaviour right across the life course. It is as often that there is social withdrawal, so it's someone that might not be well-connected or have friends and friends and family, but… some people are naturally hoarders… And then a lack of concern or understanding themselves that this is a situation they've got themselves into."
Some are hostile towards getting help, Billings-Jensen said, complicating efforts to help them.
"What the report points to … is that it's a multi-agency approach. It doesn't really sit with one group.
"One of the challenges is actually who pays for cleaning and helping people sort things out. ,There does need to be, I guess, a money trail that's attached to helping these problems resolve.
"And we know that some NGOs and other community groups work really hard to support people in local communities. It's just that there's no regular funding. It's different across the different local authorities who would be involved and who would be part of supporting people."