云南省鹤庆县自活鼠体检出鼠疫菌的一起动物间鼠疫疫情调查

Investigation on an animal plague of Yersinia pestis isolated from live rats in Heqing County,Yunnan Province

目的对2017年鹤庆县一起自活鼠体检出鼠疫菌的动物间鼠疫疫情进行调查。方法以疫点草海镇马厂村为中心进行调查,搜集自毙鼠、用鼠笼和自制的油条为诱饵捕鼠,解剖采集鼠类组织和血清,并采集调查地区的狗血清。用间接血凝试验检测鼠疫F1抗体,对采集到的鼠组织和蚤样本进行鼠疫细菌学检测和鼠疫F1抗原检测,分离到的鼠疫菌进行噬菌体裂解试验鉴定。结果共捕获鼠267只,未检获自死鼠。大绒鼠占66.29%(177/267),齐氏姬鼠占8.24%(22/267),黄胸鼠占20.22%(54/267),其它鼠种占5.24%(14/267)。鼠染蚤率为31.09%(83/267)。检获鼠体蚤165匹,其中方叶栉眼蚤占68.48%(113/165),特新蚤指名亚种占12.12%(20/165),缓慢细蚤占10.91%(18/165),其它蚤种占8.48%(14/165);获地面游离蚤1匹(缓慢细蚤)。以上样本经细菌学检验、反向间接血凝试验,从活体大绒鼠(4株)和齐氏姬鼠(1株)分离到鼠疫菌5株(前期常规监测中从活体大绒鼠分离到2株,共7株),相应鼠体脏器经反向血凝检测鼠疫F1抗原阳性,滴度从1∶1 280～1∶81 920;从3只活体大绒鼠染带的特新蚤指名亚种(2株)和方叶栉眼蚤(1株)分离到鼠疫菌3株。共采集狗血清92份、鼠血清4份,间接血凝试验检测鼠疫F1抗体均为阴性。结论鹤庆县草海镇马厂村自活体鼠、蚤分离到鼠疫菌,确定发生动物间鼠疫流行,提示应进一步加强鼠疫监测及防控。

Objective To investigate an epidemic situation of plague from live rat in Heqing County in 2017.Methods The investigation was carried out in the area around the epidemic spot Machang Village in Caohai Town and the self-dead rodents were collected.The rat cages and self-made oil strips were used as bait to trap the rodents.The murine tissues and serum were dissected and the dog serum of the survey area was collected.Indirect hemagglutination test was used to detect the antibody against to plague F1.Bacteriological examination and antigen detection of plague F1 were carried out in collected samples of the rodent tissues and fleas,and isolated Yersinia pestis were identified by phage cleavage test.Results A total of 267 mice were captured and no dead rats were detected.The Eothenomys miletus accounted for 66.29%(177/267),Apodemus chevrieri accounted for8.24%(22/267),Rattus tanezumi accounted for 20.22%(54/267),and the other species accounted for 5.24%(14/267).The rate of flea infection in rodents was 31.09%(83/267).Among 165 fleas,68.48%(113/165)Ctenophthalmus quadratus were picked up,12.12%(20/165)were named Neopsylla specialis,Leptopsylla segnis accounted for 10.91%(18/165),other kind of fleas accounted for 8.48%(14/165);and 1 flea was found on the ground(Leptopsylla segnis).The above samples were isolated from live Eothenomys miletus(4 strains)and Apodemus chevrieri(1 strain)to 5 strains of Yersinia pestis by bacteriological test and reverse indirect hemagglutination test(previously isolated from live Eothenomys miletus in routine monitoring 2 strains,a total of 7 strains),the corresponding rat organs were positive for plague F1 antigen by reverse hemagglutination,titer from 1∶1 280~1∶81 920;from the three live Eothenomys miletus rats dyed the Neopsylla specialis(2 strains)and Ctenophthalmus quadratus(1 strain)were isolated from 3 strains of Yersinia pestis.A total of 92 dog serum samples and 4 mouse serum samples were collected.Indirect hemagglutination test was used to detect plague F1 antibodies.Conclusion Machang Village,Caohai Town,Heqing County,was isolated from live squirrels and plague bacteria,and the occurrence of plague epidemics in animals was confirmed,suggesting that we should further strengthen the plague monitoring and prevention and control work.