Taiwan, being located in the subtropics, is naturally a hotbed for the spread of communicable illness. In addition, in recent years tourism has developed, travel to mainland China has been allowed, and foreign labor has been brought into Taiwan. As a result of such factors, diseases that had been totally wiped out in Taiwan have come back into the country, creating the possibility of epidemics.
地處亞熱帶的台灣，本來就是傳染病流行的溫床，再加上近年觀光事業發達、開放大陸探親、引進外勞…… 等諸多因素，使得原本在台灣已經根絕的傳染病，都有境外移入、造成流行的可能。