Day care helps fight off cancer

Children who attend day-care centres or playgroups have a 30 per cent less chance of developing a life-threatening cancer, a study has found.

Researchers found that children who had regular contact with their peers and exposed to a large number of infections were more likely to develop a stronger immune system, helping them fight the development of the most common form of childhood cancer, acute lymphoblastic leukaemia.

The research, which looked at 14 studies involving more than 20,000 children, is the first to make a link between social contact and leukaemia, which affects about one in 2000 youngsters aged between two and five as reported in The Age.

Professor of epidemiology at the University of California, Patricia Buffler, said "It is known that environments such as day-care centres increase the chance of infections spreading".

"Some proponents of the theory believe that if the immune system is not challenged early in life and does not develop normally, it may mount an inappropriate response to infections encountered later in childhood and that this could provoke the development of leukaemia."

Scientists believe that for most types of childhood leukaemia to develop, there first must be a genetic mutation in the foetus, followed by a second trigger during childhood that results in 1 per cent of those children developing the disease. Infection is one of the suspected triggers.

"The president of Childcare Associations Australia, Amanda Morphett, said the findings indicated that "well regulated, quality assured care has a positive impact on children's growth and development".

"If there is an upper respiratory, viral or gastro type of infection to be caught, children who are new to care tend to be the first to catch it, [but] anecdotal evidence suggests that those who have participated in high social contact situations are better able to manage exposure to both viral and bacterial infection," she said.