Children's Commissioner sends strong message out through social media.

"Child poverty - it's not choice." That's the message that outgoing Children's Commissioner Dr Russell Wills wants to spread through social media in a challenge to Government policy.

His latest annual Child Poverty Monitor, out today, says children living in households earning below 60 per cent of the median household income after housing costs, have almost doubled from 15 per cent of all children in 1984 to 29 per cent last year. Children hospitalised with poverty-related illnesses more than doubled in the 1990s and have increased further in the recent recession.

"Everything points to things being far tougher than they were 30 years ago. That's not right in a country like ours and it's not fair," said Dr Wills, whose five-year term as Children's Commissioner ends in June. "Today I'm asking New Zealanders to show they share our concern by spreading the message #itsnotchoice. If they visit our website they can take part in a selfie campaign and show that we're all behind the need for things to change for our kids."

Political scientist Dr Bryce Edwards said the message was "a beautiful contrast" with Prime Minister John Key's claim in 2011 that "anyone on a benefit actually has a lifestyle choice".


Dr Edwards said it was unusual for a public official to lead a social media campaign on such a contentious issue.

"It's not normally the case that you have a government agency that is attempting to mobilise citizens on a political issue, especially one that isn't necessarily in tune with the Government of the day."

But Dr Wills said the message was not aimed at Mr Key's comments.

"It has a double meaning," he said. "It's not 'choice', meaning it's not a good thing. It's also not the children's choice."

The social media campaign asks people to print out and complete a sign saying, "Child poverty has doubled since the 80s. This is ..."

The Child Poverty Monitor is produced jointly by Dr Wills' office and Otago University and is funded by the J R McKenzie Trust.

Otago epidemiologist Dr Jean Simpson said the increase in children hospitalised with poverty-related illnesses since 2007 was driven by more respiratory and viral infections associated with cold, damp and overcrowded houses. Housing costs have risen, and more are renting.

However the number of children living in material hardship jumped from 14 per cent in 2007 to 21 per cent in 2011 but has dropped back to 14 per cent.

Social Development Minister Anne Tolley said benefits would rise in April by $25 a week for every family with children and in-work tax credits for working families would rise by up to $12.50 a week. Labour MP Jacinda Ardern said the increases were not enough.

Labour promised last year to pay an extra $60 a week for most children up to age 3.