Tauranga parents who excessively clean their homes are stopping their children from developing immunity to illnesses, experts say.
Childcare experts said parents might not like seeing their child get ill but the common cold could actually help boost a child's immunity.
"Being exposed to germs is how a child builds up an immunity," said Juni Uni pre-school owner Sam Gordon.
The issue has been hotly debated across the Tasman since the release of Australia's National Health and Medical Research Council guidelines which recommended children bring their own cupcake and candle on their birthday "to prevent germs spreading when children puff over a shared cake".
It also recommended children and adults wash their hands with soap or sanitiser before and after playing in a sandpit, and daycare staff wash toys, cushion covers, taps, doorknobs and floors daily. Bench tops, door handles and taps were identified as breeding grounds for germs could help cold and flu viruses spread. Ms Gordon said the guidelines were ridiculous.
"Children have been blowing out candles for years ... and the infections that can spread are natural and your body can build up a resistance to them."
She was aware of extreme cases of obsessive compulsive parents who cleaned everything - "and that strips a child's immunity".
"We have got low incident rates of child infections ... but it's not the end of the world if a child does get a cough or a cold that can easily spread between children."
Tauranga mum Deisha Zilinois believed living in a sterile environment was a good way to keep her 5-month-old son healthy.
She bathed her son twice a day, sanitised her hands after every nappy change and kept the rubbish outside to reduce the spread of germs.
"I do keep my house very clean but I do believe children should get outside and play in the dirt. I don't like the idea of my son getting sick but I know he needs to build up a resistance [to germs]," she said.
Tauranga Regional Free Kindergarten Association principal Peter Monteith said there was no substance to the recommendations and local kindergartens would not be changing procedures.
"Unlike our Australian colleagues, the Health Research Council of New Zealand does not have any role developing health guidelines, other than funding health research that might produce evidence that guideline developers might use."
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