Type 1 diabetes (T1D) is a heterogeneous disorder characterized by destruction of pancreatic beta cells, culminating in loss of insulin secretion. Data from large epidemiologic studies worldwide indicate that during the last decades the incidence of T1D has increased significantly, reaching percentages of 2-5% annually. This increase suggests that there is a significant environmental contribution impacting the development of the disease, since genetic factors alone can hardly explain the rapid increase. Studies regarding T1D epidemiology in diverse populations aim to identify the disease causal factors and new targets for intervention. Viruses are one of the environmental factors implicated in the development of T1D in susceptible individuals. Recent studies suggest an association of T1D with H1N1 influenza. We would like to comment on this association and report our experience. Prospective studies are necessary to assess whether H1N1 infection is involved in T1D pathogenesis and provide directions on how to deal with viral infections in diabetes-susceptible individuals.