Prime Minister Stephen Harper says he doesn’t understand why people in the developed world don’t get vaccinated.

Harper, speaking alongside Melinda Gates in an exclusive TV interview with the CBC’s Hannah Thibedeau, said vaccinations have been “lifesavers” in our society and elsewhere.

“It's hard for me not to get very emotional about this because we know, we scientifically know, what vaccinations and immunizations have done for us, personally, in our generation and for generations after us,” he said on the second day of the government's maternal, newborn and child health summit.

“I frankly don't understand people who are walking away in our society from something that's proven to work.”

Gates, whose Bill and Melinda Gates Foundation is one of the largest in the world, expressed the same sentiment.

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Melinda Gates, co-founder of the Bill & Melinda Gates Foundation, says meeting the world's goals of reducing maternal and child mortality would take 'very simple interventions.' (Nathan Denette/Canadian Press)

"As a parent, the responsible thing to do — if you love your child — is to vaccinate your child," she said.

"We so take advantage, take for granted, vaccines in the U.S. or in Canada, that we forget what those diseases were, and what a scourge they were, to children before."

Harper then offered his advice to those who "go off on their own theories and not listen to the scientific evidence."

"Don't indulge your theories, think of your children and listen to the experts," he said.

'Simple' interventions to save lives

Vaccinations, they said, will be a key factor in achieving the goal of reducing maternal and child death rates by 75 per cent. It's part of what Harper and Gates describe as "simple" interventions.

Harper said the world has reduced the death rates by about 45 per cent but "one would hope" that with further action, "we would finally achieve that goal" by 2020.

And it wouldn't be difficult.

"Right now, it's vaccinations for children who are under five — hugely effective tool," said Gates.

"But for newborns, it's making sure very simple things — teaching a mother to immediately and exclusively breastfeed, teaching proper cord care — things you all do in Canada — keeping the baby warm, having a $5 mask to resuscitate the baby 'cause a lot have birth asphyxia.

"Those are very simple inexpensive interventions that can cut down that number of children who die in that first month of life," she said.

Thibedeau's interview with Gates and Harper will air tonight on CBC News Network's Power & Politics and on The National.