A vet is calling for an investigation into a toxin in wild pigs that affects dogs and might also make humans sick.
Subi Babu remains in a critical care in Waikato hospital, while her husband and mother-in-law are in a stable condition.
Vet Jenni Peterson said dogs suffer from an illness commonly known as "Go Slow" when they eat wild pork.
Ms Peterson said within minutes they collapse and get the shakes.
She said it was worrisome very little was known about the toxin, and there had been no investigation into whether humans can also suffer.
Friends of the family hospitalised are trying to help relatives travel from India to take care of their two young children.
Shibu Kochummen, his wife Subi Babu, and his mother Alexkutty Daniel - who is visiting from India - are in Waikato Hospital.
When emergency services arrived at the house on Saturday, they found the three adults unconscious and the couple's two children, aged 1 and 7, asleep in bed, family friend Joji Varghese said.
Mr Varghese said he last saw the Putaruru-based family yesterday afternoon, and they remained unresponsive.
"If you mean by consciousness do they open their eyes? Then yes. But once the eye is actually open, do they register anything? The answer is no," he said.
Mr Varghese said doctors were unable to treat them until they determined the exact cause of the infection.
"What the doctors are trying to do is prevent secondary infection from affecting them because their body is so weak to start with," he said.
"But in terms of primary treatment, we are still awaiting on the toxicology report.
"Once that comes through, doctors will be able to say what treatment to start and timeframes associated with it."
Mr Varghese, who knows the family through their Hamilton Church, said Mr Kochummen often went out with friends who hunted. He did not hunt himself.
"In the past he's gone out with friends and they've got some game meat and stuff, and gives me a call and says there's some stuff here.
"We've cooked together and had dinner, and this time round it was the same situation," he said.
Mr Varghese said he was meant to pick up the meat on Saturday when he next saw his friends.
"That night they cooked the meat, they put the children to bed early and it was just the three adults who had the meat, and that's when the trouble started."
He said that about 15 minutes after dinner, Mr Kochummen called an ambulance but fainted halfway through the conversation.
The public health service had tested food items in the family home, and Mr Varghese said the wild boar was the only food the children had not eaten.
The children are being looked after by members of the family's church.
The seven-year-old is aware her parents are in hospital, but Mr Varghese said it wasn't ideal for the children that different carers were looking after them across the day.
Wild boar toxin 'categorically' causing collapse in dogs
Northland veterinarian Jenni Peterson has been working to discover more about an illness which affects dogs when they're given wild pork.
Ms Peterson, form Okaihau, said the illness, known as 'go slow', can be deadly and desperately needs more investigation.
It affects the mitochondria in the dogs' muscles so when they exercise they can collapse.
"We don't know what the toxin is... we don't have a test for it."
But it was "categorically" from wild pork because the illness appeared in hunting dogs given fresh meat and collapsed within minutes to hours. Meat from both wild sows and boars can carry the toxin.
Ms Peterson said 'go slow' illness was widespread throughout New Zealand and there were varying levels of severity in effects on dogs.
"Some of them, worst case scenario, die. Best case scenario - it's barely noticeable other than elevated enzymes on blood tests. The most common presentation is shaking and collapse with exercise.
"I believe it's a very under-reported disease because the vets, we don't have an answer, we don't know what causes it. Pig hunters know this and they commonly don't bring their dogs. But I would estimate maybe 20 to 30 cases a pig hunting season, through winter, that we hear about."
National Poisons Centre director Dr Adam Pomerleau said the food-borne illness botulism could not be ruled out, as it also affected nerve conduction and muscle use and could produce a "vegetative state", preventing movement and speech.
Game Animal Council head Don Hammond said people ate wild pork every day and he had never heard of anyone getting seriously ill from eating game meat.
He said he thought there was more to the illness than eating the meat.
"Thousands of people every day in New Zealand eat wild pork that's been caught in the bush. It's a major source of protein in many small rural areas, and I've never heard of anyone getting sick from meat that's been looked after properly."
Mr Hammond said it was not possible to eat enough meat to get secondary poisoning from toxins.