| In an epidemic, the international traffic accelerates the spread of infections across wide geographic areas. Policy makers are interested to know the impact on the disease transmission once the international traffic has been re-scaled. Since the pharmaceutical interventions are usually not ready in the early stage of a new epidemic, the travel restriction is a high potential intervention that should be included into the containment and mitigation strategies for officials. According to some researches, the value of the travel restriction was controversial; and most importantly, we discovered several practical and theoretical limitations in the epidemic models. These problems largely motivated us to study the effectiveness of the travel restriction on the epidemic control in both at-risk countries and the source country. In the body of thesis, new methodologies of epidemic modeling were developed by making use of the influenza A (H1N1) pandemic in 2009 as a case study. Our result showed that the travel restriction was valuable on slowing down the growth of epidemics for both at-risk countries and the source country. The time delay of the epidemic would offer public health experts, policy makers, and scientists more time for preparation and decision making on control measures. Although solely imposing the travel restriction showed little benefit on reducing the final attack rate and the probability of cases exportation, it offered additional contribution on even halting the epidemic growth once other interventions such as antiviral and hospitalization could also be implemented. Therefore, the implementation of the travel restriction must be a potential intervention to control the epidemic spread, especially for the next epidemics which could be lethal and highly intrusive. |
