Three-quarters of parents fail to remind their children to wash their hands before eating, a survey has found.
One in five don't tell them to wash their hands after going to the lavatory while one in 16 think teaching children basic hand-washing hygiene is the responsibility of schools.
The survey of 3,000 parents, carried out by The Co-Operative Pharmacy, found that 57pc failed to understand that lack of hand hygiene could result in food poisoning.
It also contributes to the rapid spread of seasonal infections like swine flu and norovirus.
The survey found that one in 25 children (4.1pc) took more than 11 days off school a year due to sickness, while 11pc took between six and 10 days off.
John Nuttall, managing director of The Co-Operative Pharmacy, said: "Our research shows that a high number of parents don't realise that they are putting their child at risk by not teaching them the basic principles of good hand hygiene.
"By promoting good habits in the home this decreases the risk of contracting serious infections, but also spreading them amongst family and friends."