Starship Children's Hospital is deferring less urgent cases to cope with a "flood" of very young children in hospital with flu symptoms.Doctors say the free under-fives flu vaccine announced for next year cannot come soon enough and will save lives.University of Auckland professor of paediatric population health, Cass Byrnes, works as a respiratory specialist at Starship.The hospital treated children from around the country but was having to put a temporary stop to some of them coming, she said.That was because, firstly, there were not enough beds for everyone and, secondly, they did not want those children to catch flu in hospital, Brynes said.There was no treatment for the virus itself but the children in hospital often needed support for serious symptoms, she said."Including supporting feeding, supporting with oxygen, or on occasion needing even more intensive respiratory support," she said."It's... scary for the child and scary for the parents," she said.Children in this year's outbreak were quite commonly presenting with non-respiratory symptoms like headaches, digestive problems and very high fever, she said.Byrnes said she could not be more relieved to see the vaccine funded for under-fives.It would save lives - but it would also prevent some children from developing breathing conditions later - sometimes long after the flu had gone, she said.It needed to come with a publicity campaign, because parents of the small group of under-fives who were currently entitled often did not realise, she said."And also starting [a campaign] early enough so people get a chance to have a think about or see the campaign two or three times in a row before thinking, 'absolutely - I need to get along there and get a vaccination'," she said.Currently children under five could get free vaccine if they had previously been hospitalised with a respiratory disease or had another serious condition.Pharmac estimated about 260,000 more children would be able to be vaccinated for free from April next year.Official statistics showed children under five were far more likely to be hospitalised or end up in intensive care with flu-like symptoms than any other age group.