London, Oct 5 (IANS): The exact cause of juvenile diabetes had eluded scientists for long and researchers have now found that a mother's exposure to viruses during pregnancy may cause type one diabetes and other auto-immune diseases in children.

In type 1 diabetes, the body does not produce insulin, a hormone needed to convert sugar, starch and other food into energy required for daily life.

Women who contract a viral infection during pregnancy transmit viruses to their genetically susceptible foetuses, sparking the development of type one diabetes, the findings showed.

"We found evidence that viral infections of the mother during pregnancy induced damage to the pancreas of the mother or the foetus, evidenced by specific anti-bodies including those affecting the pancreatic cells producing insulin," said Zvi Laron, a professor emeritus at the Tel Aviv University in Israel.

For the study, the researchers conducted blood tests of 107 healthy pregnant women, testing for islet cell autoantibodies - evidence of impending diabetes, that appears years before initial symptoms do.

The researchers also found a striking difference between women tested in different seasons, suggesting a link to winter epidemics.

During viral epidemics of the winter months, 10 percent of the healthy pregnant women, who had no family background of auto-immune diseases tested positive for damaging anti-bodies.

The study appeared in the journal Diabetic Medicine.