Te Whatu Ora says a strain of influenza that tends to hit young children the worst is spreading through Aotearoa.
It's prompted a paediatric respiratory specialist to warn parents this year's flu season will be a "nasty" one. But there is something parents can do.
We can be guilty of being complacent - but winter bugs are well and truly here.
"We're particularly anxious about influenza being a nasty season this year," said Associate Professor Cass Byrnes, from the Auckland University Department of Paediatrics.
Ads aim to encourage vaccination uptake this winter, especially for children.
"We're really promoting that all children get the influenza vaccine. It is free for six months to 12 years," Professor Byrnes said.
Respiratory infections have been trending up and yet just 8 percent of children have had the flu jab.
That's got paediatric experts worried because one of the most commonly detected respiratory viruses so far this year is Influenza B, which tends to hit young children the worst. It's also the first time since 2019 that it's circulated significantly in New Zealand.
And COVID-19 hasn't gone anywhere - two children under 10 were among 36 deaths in the past week.
"At New Shoots Children's Centres we've noticed significant sickness rolling through the centres," New Shoots Children's Centres director Michelle Pratt said.
And one of them is RSV, a virus of particular concern for doctors because it hospitalises about 3000 tamariki each year.
"It is the time of year when that starts to come as well and we have to keep vigilant because kids can get really sick with RSV," Royal New Zealand College of General Practitioners president Samantha Murton said.
Prof Byrnes says it's time we follow the US and consider nirsevimab, a single injection that protects children for the entire RSV season.
Right now, we only have a treatment called palivizumab which requires five monthly jabs.
"The parents aren't that enthusiastic about those monthly injections as you can imagine," Prof Byrnes said.
Medsafe says it hasn't received an application to fund nirsevimab. But early learning centres are keen.
"From a parents' perspective, if it was going to make a difference in terms of their ability to work and their children weren't going to get RSV and they weren't going to be significantly unwell as a result of getting RSV, certainly worth looking at," Pratt said.
Because more accessibility could be key to fewer people leaving winter bugs to chance.
