There are quite a number of asymptomatically infected in the population, and they may discharge hepatitis A virus at certain times and under certain conditions.

• 无症状感染者在人群中为数不少，在一定时期和条件下也可排出甲肝病毒，但此时带毒者常活动自如，不易管理，因而作为传染源有重要意义。