A study says children who attend daycare may build up their immunity systems to fight off childhood 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 were exposed to a multitude 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 leukemia.

The research, which looked at 14 studies involving more than 20,000 children, is the first to directly link social contact and leukemia, which affects about one in 2,000 youngsters, between two and five years old.

Patricia Buffler, study author and professor of epidemiology at the University of California, said the analysis bolstered the theory that children exposed to common infections early in life gained protection from the disease. “It is known that environments such as day-care centres increase the chance of infections spreading,” Buffler said.

“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 leukemia.”
Scientists believe that for most childhood leukemia to develop, there must be a genetic mutation in the fetus, followed by a second trigger during childhood that results in one per cent of the children developing the disease. Infection is a suspected trigger.

“There is definitely a link between cancer and infection,” Andrew Penman, chief executive of the New SouthWales Cancer Council, said. “We have seen that recently with cervical cancer, and we know that the age at which infection occurs can determine the outcome, but this research raises a lot of questions without answering any of them.”

Amanda Morphett, president of Childcare Associations Australia, said the findings indicate 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 added.

But parents should not to rush to send their child to a day-care centre on the basis on the study, warned David Ziegler, a pediatric oncologist at the Sydney Children’s Hospital.
“We’re happy to look closely at anything which can help us work out what causes leukemia, but we are talking about something that is already very, very rare, so the change for a child going to child care would be tiny,” Ziegler said. “I’d urge parents to be cautious.”