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.