The study conducted by Leeds and Newcastle Universities and the Leeds Teaching Hospitals NHS Trust analysed information from a register of more than 4,000 people living in Yorkshire, aged 0 to 29 years old, who have been diagnosed with Type 1 diabete
s.
A pattern emerged in which 'clusters' of sufferers were found at certain geographical locations and at particular times for those aged between 10 and 19.
Overall there were six to seven per cent more cases of Type 1 diabetes found in 10 to 19-year-olds in these so-called clusters than would have been expected by chance.
This pattern, called 'space-time clustering', is typical of conditions triggered by infections and adds weight to the theory that environmental factors can trigger the development of the disease, say the researchers.
Environmental factors include poor air quality, water pollution, viruses, breast feeding and diet.
But Richard Feltblower, a paediatric research statistician at the University of Leeds, stressed none of these had yet been linked with Type1 diabetes.
He said: "It is difficult to speculate about that. And we don't actually know which of these environmental factors might trigger the diabetes.
"Interestingly though, studies have shown children who go to nursery from a young age are less susceptible to Type 1. It is as though they have built up a kind of immunity."
Children
A quarter of a million people in the UK have Type 1 diabetes, and the number of cases in children is rising by three per cent a year.
It develops if the body is unable to produce any insulin and usually appears before the age of 40.
Previously it has been suggested that infections are linked to the development of Type 1 diabetes in children genetically susceptible to certain environmental triggers.
Females with the condition were likely to live near to one another, rather than be scattered across a wider area, the current study found.
The results have been published in the academic journal Diabetologia.
Leading researcher Dr Richard McNally, of Newcastle University's school of clinical medical sciences for child health, said: "This research brings us closer to understanding more about Type 1 diabetes.
"However, it's just one piece in the jigsaw and much more research is needed before we can identify which infections may be to blame and thus inform advice on preventative measures.
"The condition is likely to be caused by an interplay of factors, of which infections are just one element."
Simon O'Neill, director of care and policy at Diabetes UK, said: "We always suspected that common infections could be a trigger for Type 1 diabetes in those who are already genetically susceptible. This research provides vital evidence in supporting this link.
"The fact that the number of cases of Type 1 diabetes is rising by three per cent a year cannot be explained by genetics alone. This research reinforces the idea that common infections and environmental factors also play a part."
sophie.hazan@ypn.co.uk