infective fistula of semicircular canal

例句：

1. 1.The disease is infective and can spread quickly.
   这种疾病具有传染性，可以迅速传播。
2. 2. The virus is highly infective and poses a serious threat to public health.
   这种病毒具有很强的传染性，对公共卫生构成严重威胁。
3. 3. The infective agent of the disease was identified as a new strain of bacteria.
   该疾病的感染源被确认为一种新的细菌菌株。