World's richest man and global health campaigner Bill Gates has a very direct message for Australian parents tossing up whether or not to vaccinate their children.
'Vaccinate your children.'
The Microsoft founder turned philanthropist has helped lead the push to vaccinate some of the world's poorest people in some of the most remote corners of the globe.
He has little patience for rich country couples opting not to give their children their shots.
He says such people are misguided and it's a particular problem when parents convince other parents not to vaccinate, leading to clusters of unvaccinated children in particular schools.
'It causes death,' he told an audience in Canberra on Tuesday. 'Vaccines are there to protect people and thank goodness they've been tested and used hundreds of millions of times.'
Mr Gates' comments came as NSW moved to toughen laws to ensure children who haven't had their shots will be expelled from childcare centres or banned from enrolling.
Mr Gates said some American states had implemented similar laws.
'Ideally we could have people learn that it's beneficial - that would be the simplest thing,' he said.
NSW's move followed a report that said tens of thousands of children were behind with their vaccinations and at risk from contagious diseases.
Parents were either rejecting the scientific evidence and electing not to immunise their kids, or simply forgetting, the report said.