Because there is at this stage no acquired immunity, the bacilli multiply rapidly, eliciting an exudative inflammatory response in which polymorphonuclear leucocytes and monocytes predominate.

• 因为在此阶段并无后天免疫,杆菌繁殖迅速,从而引起渗出性炎症反应,其中以多形核白细胞和单核白细胞居支配地位。