[名词解释] 磨蚀作用

寄生虫病的流行特点是指 ["A．社会性，自然性","B．人源性，动物性","C．季节性，地方性，自然疫源性","D．隐匿性，暴发性","E．群体性，广泛性"] 吹蚀 易感人群是指 ["A．老年人","B．婴幼儿","C．对寄生虫缺乏免疫力的人","D．成年人","E．具有先天性免疫力的人"] 生活史中仅有有性生殖的寄生虫是 ["A．蛔虫 ","B．蓝氏贾第鞭毛虫 ","C．利什曼原虫 ","D．阴道毛滴虫 ","E．阿米巴原虫"] 风积现象 磨蚀作用