New enteroviruses associated with type 1 diabetes have been found, which opens up new therapeutic and diagnostic implications. A vaccine against at least one enterovirus selected from coxsackie A virus CAV4, CAV5, CAV6 and echovirus 18 is provided for use in preventing or treating type 1 diabetes. A diagnostic assay for predicting the risk of contracting type 1 diabetes based on the determination of said enteroviruses is also provided.
