Viral infections could play a role in the development of Type 1 diabetes after researchers found children with the condition were nearly 10 times as likely to have a virus than healthy children.
Experts from Sydney, Australia, reviewed 24 studies on the issue, involving more than 1,900 people with Type 1 diabetes, or a related condition known as pre-diabetes.
Most of the participants were children, the time when Type 1 usually develops.
The researchers found a strong association between enterovirus and Type 1 diabetes.
Enterovirus refers to a collection of viruses which can cause a range of symptoms, including fever, cold, rash, sickness and diarrhoea.
While they said the findings ‘cannot prove’ that enterovirus infection causes diabetes, the results provide ‘additional support to the direct evidence of enterovirus infection in pancreatic tissue of individuals with type 1 diabetes’.
Writing in the British Medical Journal (BMJ), the authors concluded: ‘Our results show an association between Type 1 diabetes and enterovirus infection, with a more than nine times the risk of infection in cases of diabetes and three times the risk in children with autoimmunity.
‘The odds of having an enterovirus infection in people with established diabetes suggest that persistent enterovirus infection is also common among patients with type 1 diabetes.’
Type 1 diabetes is believed to be caused by a complex relationship between genetic factors, the immune system and the environment.
Some 300,000 people in the UK have Type 1 diabetes.
The authors said genetics alone could not explain the rising numbers of people with the condition worldwide.
‘In recent decades there has been a rapid rise in the incidence of childhood Type 1 diabetes worldwide, especially in those under the age of five,’ they said.
‘In Europe, from 1989-2003 the average annual increase was 3.9 per cent, too fast to be accounted for by genetics alone.’
In an accompanying editorial, Professor Didier Hober and Famara Sane from the University of Lille in France, said enteroviruses and Type 1 diabetes are clearly linked, but the mechanism is yet to be explained.
They conclude: ‘The association between enteroviruses and Type 1 diabetes opens up the possibility of developing new preventive and therapeutic strategies to fight this disease.’
Dr Iain Frame, director of research at Diabetes UK, said: ‘We’ve known for some time that the development of Type 1 diabetes cannot be explained by genetics alone and that some other environmental triggers must play a part.
‘Many factors have been reported as being associated with Type 1 diabetes but that is not the same as causing Type 1 diabetes and this report based on looking at a number of previous studies does not bring us much closer to pinpointing the causes of Type 1 diabetes.
‘We do, however, welcome any new analysis that brings about a better understanding of the involvement of certain viruses on the insulin-producing cells in the pancreas.
‘It may well give us another piece of the jigsaw in working towards a better understanding of the causes of Type 1 diabetes which should in turn lead to new prevention strategies.’
By Daily Mail Reporter
Daily Mail