广东省65株耶氏菌的系统鉴定与鼠疫疫源地性质的探讨

Indentify of 65 strains of Yersinia and study on character of plague focuses in Guangdong

目的鉴定65株耶氏菌,了解菌株的生物学特性,抗原抗体与鼠疫菌的相关性,探讨疫源地的现状和性质。方法65株菌用3种致病性耶氏菌诊断血清,分别做玻片、试管凝集试验、生化试验、生长特性,挑选14株菌做毒力因子、毒力基因、致病性、交叉免疫原性、动物试验和血清学、药敏试验。结果 63株小肠结肠炎耶氏菌血清型42株O∶3、21株O∶9,中间型1株,假结核血清II型1株;VW+2株,VW±10株,VW-2株;14株菌F1Ag、F1Ab全阴;小肠结肠炎5株菌均有2个毒力基因(ail、ystA)阳性,VW+和VW±对小白鼠、家兔有致病性,动物感染一种耶氏菌后有交叉免疫力,抗原、活菌交叉吸收鼠疫抗血清后血清学IHA、RIHA没有交叉性,常用抗菌素敏感。结论目前动物感染小肠结肠炎菌普遍,猪感染最高,局部已爆发流行,假结核菌偏低,鼠疫处于静息期。

Objectives To identify 65 strains of Yersinia, to investigate biological characteristics of these Yersinia , and the rela- tivity between Y. pestis and antigen and antibody to research the status quo and nature of plague focus. Methods Serum aggluti- nation assay with diagonal serum of 3 kinds of Yersinia, biochemical tests, biological features were respectively performed with 65 strains Yersinia. Virulence factors, virulence gene, pathogenicity, cross - immunity, animal tests, serological tests and drug sen- sitivity tests were respectively conducted with 14 strains Yersinia. Results There are 63 strains of Y. enterocolitica （42 strains are 0： 3 serological type and 21 strains are 0： 9 serological type ）, one strain was Y. intermedia and one strain was Y. pseudotubercolosis. 2 strains were vw ＋ , 10 strains were vw ＋ , 2 strains were vw -. FlAg and F1Ab of 14 strains were nega- tive. There were two virulence gene （ail, ystA ） exist in 5 strains of Y. enterocolitica , vw ＋ and vw ± strains were pathogenic to white mouse and rabbit. Cross immunity existed in animals when were infected by Yersinia. Cross reaction was nonexistent be- tween 3 kinds of Yersinia （ Y. enterocolitica, Y. pseudotubercolosis, Y. intermedia ） and Y. pestis （ IHA, RIHA ）. These Yersini- awere sensitive to common antibiotics. Conclusions The Y. enterocolitica - carrying rate of animal in Guangdong is universal, the Y. enterocolitica - carrying rate of pig is the highest even breaks out in some areas. The Y. pseudotubercolosis - carrying rate of animal is low. Plague focus of Guangdong is in resting stage.