In an analysis of data on children, a team of scientists at the Helmholtz Zentrum München has found that viral respiratory infections during the first six months of life are associated with an increased risk for type 1 diabetes.
Led by Prof. Dr. Anette-Gabriele Ziegler, Director of the Institute of Diabetes Research (IDF) at Helmholtz, the scientists examined anonymized data from almost 300,000 children born in Bavaria between 2005 and 2007. This is 85 percent of all newborns in Bavaria during this period. The data material was provided by The Kassenärztliche Vereinigung Bayern (KVB – Bavarian Association of Statutory Health Insurance Physicians) for research purposes.
The infections were categorized by location of symptoms (such as dermal, eye, gastrointestinal or respiratory infections), causes (bacterial, viral or mycoses) and age (quarter-yearly from birth). Dr. Ziegler’s team systematically evaluated all available data on infections with respect to the later development of type 1 diabetes.
Explains Dr. Andreas Beyerlein, the study’s first author:
“Our findings show that viral respiratory tract disorders during the first six months of life significantly increase the risk of children developing type 1 diabetes.”
Infections that happened later or that involved other organs were not associated with a significantly higher risk. For the researchers, these findings are a further piece in the puzzle of learning how type 1 diabetes develops. The interaction of genetic and environmental factors in diabetes is still largely unclear.
Up until now there were only relatively inconsistent indications from studies with children with a genetically higher risk of type 1 diabetes regarding the influence of infections.
“Now for the first time we were able to confirm this in a population-based dataset of almost 300,000 children. In particular, we found strong indications that the first six months are an especially sensitive stage in life,” explains lead scientist Ziegler. “This is also consistent with other results that we have published based on data from children with increased familial risk, which already suggested that the first half year of life is crucial for the development of the immune system and of autoimmune diseases such as type 1 diabetes.”
Moving forward, the team would like to determine if there is in fact a causal relationship and if so, precisely which pathogens are involved and how they trigger this effect. The results could then create a basis for trying to develop an appropriate vaccine.
Image: Razza Mathadsa/Flickr