Rattus norvegicus at the same time foci of the port city and its nearby inland areas there are sudden plague of the risk factors, including ocean-going freighter input and the possibility of renewal.

• 同时家鼠疫源地的各港埠城市及其临近的内陆地区也存在突发鼠疫的危险因素，包括远洋货轮输入和复燃的可能。