The article is based on data from the ongoing POInT* study where researchers are investigating if it is possible to stop the development of type 1 diabetes in children with genetic risk of developing the disease by giving them preventive oral insulin treatment. The collected blood samples also make it possible for researchers to study the connection between type 1 diabetes and certain viruses, such as the coronavirus, to better understand how type 1 diabetes develops. Paediatrician Helena Elding Larsson is scientifically responsible for the Swedish part of POInT and a coauthor of the article in JAMA. 

“During the pandemic, not many other viruses were circulating, which allowed us to  study the connection between a new virus and the development of diabetes-related autoantibodies. The Swedish children who participate in the study are making a significant contribution to an international study that helps us understand how type 1 diabetes develops and may be prevented in the future”, says Helena Elding Larsson, professor of autoimmune diseases at Lund University Diabetes Centre and head of the paediatric department at Skåne University Hospital. 

Particularly sensitive age 

The researchers studied the development of diabetes-related autoantibodies and antibodies against the coronavirus in 885 children in Germany, Poland, Sweden, and Great Britain, aged four months old and two years old during the period of April 2018 until June 2022. Out of the children, 170 developed antibodies against the coronavirus during the period, which suggests they had had Covid-19. 

The children who had had a Covid-19 infection had an approximately twofold risk of developing diabetes-related autoantibodies compared to the children that had not been infected by the virus. The study also shows that the increase in the risk was higher in children who had the infection before 18 months of age, and it was the highest in children who were around 12 months old when they had Covid-19. 

“Children that were infected at age one had around five to ten times as high a risk of developing diabetes-related autoantibodies compared to children of the same age who were not infected. The results indicate that children with a genetic risk of type 1 diabetes are particularly sensitive to certain viral infections at that age”, says Ezio Bonifacio, professor at the TUD Dresden University of Technology who led the study. 

Certain viral infections 

Previous research has shown that there is a connection between enterovirus infection and the development of autoantibodies and type 1 diabetes. The researchers behind the new study also followed up antibodies for the influenza virus but found no connection between influenza virus and the development of diabetes-related autoantibodies. This indicates that certain viruses seem to be of importance in the development of type 1 diabetes. 

“The study adds to the evidence base that there is a connection between certain viral infections and the development of diabetes-related autoantibodies, which are used to identify individuals who are at risk of developing type 1 diabetes later in life. At the same time, a lot of research suggests that several factors interact in the development of type 1 diabetes. Our new study is a piece in the jigsaw puzzle we are completing in our effort to understand the disease”, says Helena Elding Larsson. 

Important to train the immune system 

Humans carry the immune system cells from birth, and these cells develop when we are exposed to viruses and bacteria. Most viruses are harmless, but some may lead to serious illness. Helena Elding Larsson still wants to emphasise that small children need to be exposed to viruses to strengthen their immune system. 

“In most cases, parents of small children should not fear viruses, regardless of whether the child has an increased risk of developing type 1 diabetes or not. Children need to have infections and develop their immune system. It may become evident that we should protect children at higher risk of type 1 diabetes from certain viruses that increase the risk of getting the disease, but first we need to perform vaccination studies to draw safe conclusions and develop new treatments”, says Helena Elding Larsson. 

Link to the press release from TUD Dresden University of Technology