Epidemic hemorrhagic fever (EHF) is a zoonoses hantaviruses-transmitted by rats in natural foci. EHF victims show the following symptoms: high fever, hemorrhage, shock and renal failure, with the c haracterization of rapid onset, high infection and high fatality. Moreover, labo ratiory animals could get the disease from the sick wild rats, which would resul t in laboratory infection with the technicians involved. It is imperative for se rum samples to be taken to monitor EHF infection as one of the quality standards of laboratory animals in China.