五、戊型肝炎【病原和流行病学】戊型肝炎病毒（hepatitisEvirus，HEV）属嵌杯病毒科，无包膜，核酸为单股正链RNA。
O O B-dis I-dis I-dis I-dis O O O O O O O O O B-mic I-mic I-mic I-mic I-mic I-mic O B-mic I-mic I-mic I-mic I-mic I-mic I-mic I-mic I-mic I-mic I-mic I-mic I-mic I-mic I-mic O B-mic I-mic I-mic O O B-mic I-mic I-mic I-mic O O O O O O O O O O O O O O O O O