We applaud Shih et al. (1) for using enterovirus (EV) infection as a time-dependent covariate and time to type 1 diabetes (T1D) onset as the outcome to examine the relationship between EV infection and the incidence of T1D. The authors excellently obtained isolation numbers for the top five EV serotypes from a nationwide laboratory surveillance system of the Taiwan Centers for Disease Control (Taiwan CDC) to correlate the Taiwan T1D incidence with different species of EV infection. However, we have some concerns regarding using the decreasing trend of EV infection to explain the decreasing trend of T1D incidence in Taiwanese adolescents.
