Objective It has been hypothesized that SARS-CoV-2 infection in children can increase risk of developing type 1 diabetes. Research Design and Methods We undertook a prospective analysis based on all children in Denmark where we investigated the association between SARS-CoV-2 infection and subsequent risk of type 1 diabetes, using information from several different national Danish registers. Denmark had one of the highest test-rates per capita in the world during the pandemic. Results We did not observe a higher risk of a first time diagnosis of type 1 diabetes in children 30 days or more after a positive SARS-CoV-2 test, compared to children with a history of only negative SARS-CoV-2 tests (Hazard ratio 0.85, 95% CI 0.70, 1.04). Conclusions Our data do not support that SARS-CoV-2 infection is associated with type 1 diabetes, or that type 1 diabetes should be a special focus after a SARS-CoV-2 infection in children.

The authors have declared no competing interest.

No specific funding was obtained for this work.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The Danish study was performed as a surveillance study as part of the governmental institution Statens Serum Institut's (SSI) advisory tasks for the Danish Ministry of Health. SSI's purpose is to monitor and fight the spread of disease in accordance with section 222 of the Danish Health Act. According to Danish law, national surveillance activities conducted by SSI do not require approval from an ethics committee. It was approved by the Danish Governmental law firm and SSI's compliance department that the study is fully compliant with all legal, ethical and IT-security requirements and there are no further approval procedures regarding such studies.

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