Like dysentery, typhus, diphtheria, the epidemic brain keel turns the membrane inflammation and hepatitis B and so on, may have the recovery period cause of disease carrier.
如痢疾、伤寒、白喉、流行性脑脊翻膜炎和乙型肝炎等，都可以有恢复期病原携带者。
3
Objective to identify the cause and transmission route of hepatitis a, to analyse the epidemic fac - tors and to evaluate the control effect.