A variety of viruses including the infectious mononucleosis virus can be causes of hepatitis but the usual forms are infectious hepatitis and serum hepatitis.

• 许多种病毒，包括传染性单核细胞增多症病毒都可能是肝炎的病因，但常见的病毒类型是传染性肝炎病毒和血清性肝炎病毒。