应用鸡胚分离法分离人感染H7N9禽流感病毒的研究

Study on the isolation of human infection with avian influenza A(H7N9)virus by using embryonated chicken eggs

目的 建立人感染H7N9禽流感病毒鸡胚分离法，并用病毒分离株进行血清抗体检测。方法 用SPF鸡胚接种人感染H7N9禽流感确诊病例的呼吸道标本，培养72 h后收获羊水和尿囊液测定血凝效价（HA）。用2株病毒分离株检测福建省首例患者急性期、恢复期及密切接触者血清抗体。结果 经鸡胚盲传2代后，5例患者的咽拭子标本均分离出该病毒。第2代分离物HA滴度（1∶32～1∶256）较第1代（1∶8～1∶32）明显提高。2株病毒分离株检测感染者血清，恢复期血清HI抗体滴度较急性期升高16倍，且2株检测结果一致。结论 用鸡胚分离法分离人感染H7N9禽流感病毒敏感性高，感染者在短期内可产生高滴度的HI抗体。

Objective To establish a viral isolation method in vitro of human infection with avian influenza A（H7N9） virus by using embryonated chicken eggs, and detect the H7N9 antibody. Methods The swab specimens from confirmed HTN9 cases were inoculated into SPF embryonated chicken eggs. The amniotic fluid or urine of eggs were collected and the HA titers were detected after 72 hours. Two isolates were used for titration of HI antibody, which existed in acute, convalescent phase serum in confirmed cases and close contact individuals. Results Five isolates of H7N9 virus were obtained by two passages of egg in- oculation from swab specimens collected from all five confirmed cases in Fujian. The HA titers （1： 32-1： 256） of isolates ob- tained from second passage were higher than that from the first passage （1： 8-1： 32）. The HI titer of convalescent serum were 16 times increasing in comparison with acute phase serum and shown the same detection results for the two isolates. Conclusion The inoculation of embryoanted chicken eggs was a sensitive method for H7N9 virus isolation. The high HI titers can be found from the H7N9 cases in a short period time.