Detecting a trend change in cross-border epidemic transmission

A method for detecting a trend change in a multiregional epidemic is developed for a standard epidemiological SIR compartment model and a meta-population network model. The method is applicable to the investigation of the efficacy of the implemented public health intervention from a time series of the number of new cases reported in multiple geographical regions. The change point of the probability of movements was one week after the WHO worldwide alert on the SARS outbreak. The alert was effective in controlling travels. The probability of infection did not change for three weeks. Public health intervention after the alert took few effects. The probability of movements did not change at all for the flu pandemic. The pandemic did not affect travels despite the WHO alert. The change point of the probability of infection was one week after the WHO alert. School closures, cancelling large mass gatherings, and social distancing were effective in controlling exposure for children and young adults.