O1群霍乱弧菌毒力基因和菌株流行能力关系研究

发布时间：2018-11-11 11:11

【摘要】：目的调查福建省1962-2005年不同流行时期、不同流行血清型的O1群埃尔托型霍乱弧菌(EVC)毒力基因分布情况;探讨霍乱弧菌(VC)不同毒力基因特征与霍乱流行能力的关系。方法运用PCR扩增技术,检测1962-2005年69株(稻叶21、小川48)霍乱患者分离株的ctxA基因,同时进行ctxB、tcpA、rstR、hlyA毒力因子的古典型(Cl)和埃尔托型(El)基因亚型的扩增;结合流行病学资料分析不同毒力特征菌株的流行能力。结果 69株O1群霍乱弧菌ctxA基因阳性62株,ctxA基因阴性的菌株均不同程度地携带有其他各相关毒力基因;各毒力因子古典型和埃尔托型的阳检率分别为ctxB60.9%(42株)和72.5%(50株),rstR37.7%(26株)和72.5%(50株),tcpA4.35%(3株)和69.57%(48株),hlyA65.22%(45株)和79.71%(55株)。ctxB-Cl、rstR-Cl基因以及菌株同时携带rstR-Cl和rstREl基因的阳性率在稻叶型(阳性率分别为38.1%、0和0)和小川型(阳性率分别为70.8%、54.2%和35.4%)菌株中的差异有统计学意义(P均0.05)。ctxB-El、rstR-Cl、rstR-El基因的阳性率在1962-1964年、1978年、1994-2000年的小川型3个不同流行时期(阳性率分别为ctxB-El:100.0%、100.0%、44.8%;rstR-Cl:0、0、89.7%;rstR-El:100.0%、87.5%、58.6%)的差异有统计学意义(P均0.05)。ctxB-Cl、ctxB-El、rstR-El基因的阳性率在1980-1986年、2005年稻叶型两个不同流行时期(阳性率分别为ctxB-Cl:13.3%、100.0%;ctxB-El:100.0%、66.7%;rstR-El:93.3%、50.0%)的差异有统计学意义(P均0.05)。结论福建省1962-2005年O1群霍乱菌株不同程度地携带有相关的毒力因子;各毒力因子埃尔托型基因片段的检出率均要高于古典型,以rstR和tcpA基因的差异最明显;相对于稻叶血清型,小川血清型更容易整合古典型的ctxB和rstR基因片段;ctxB和rstR基因的类型和不同血清型霍乱菌株的流行能力有相关性。
[Abstract]:Objective to investigate the distribution of virulence genes of Vibrio cholerae (EVC) in different serotypes of Vibrio cholerae O1 during 1962-2005 in Fujian Province, and to explore the relationship between the characteristics of virulence genes of Vibrio cholerae (VC) and the epidemic ability of cholera. Methods PCR amplification technique was used to detect the ctxA gene of 69 cholera isolates (Oryza japonica 21, Xiaochuan 48) from 1962 to 2005. The classical (Cl) and (El) subtypes of ctxB,tcpA,rstR,hlyA virulence factor were amplified at the same time. Epidemiological data were used to analyze the epidemic ability of different virulent strains. Results 62 strains of 69 strains of Vibrio cholerae O1 were positive for ctxA gene, and all the strains with negative ctxA gene carried other virulence genes to some extent. The positive rates of ctxB60.9% (42 strains), rstR37.7% (26 strains) and Elto type (50 strains), tcpA4.35% (3 strains) and Elto type (48 strains) were 72.5% and 72.5%, respectively. HlyA65.22% (45 strains) and 79.71% (55 strains). The positive rates of ctxB-Cl,rstR-Cl gene and rstR-Cl and rstREl gene were 38.1% in rice leaf type. There were significant differences between 0 and 0 strains and Ogawa type (70.842% and 35.4%, respectively). The positive rate of ctxB-El,rstR-Cl,rstR-El gene in 1962-1964, 1978, was significantly higher than that of Ogawa type (P < 0. 05, P < 0. 05), and the positive rate was 75. 8% and 35. 4% respectively (P < 0. 05). Three different epidemic periods of Ogawa type (positive rate: ctxB-El:100.0%,100.0%,44.8%;) in 1994-2000 RstR-Cl:0,0,89.7%; The positive rate of ctxB-Cl,ctxB-El,rstR-El gene was from 1980 to 1986. In 2005, the positive rate of rice leaf type was ctxB-Cl:13.3%,100.0%; in two different epidemic periods. The difference of ctxB-El:100.0%,66.7%;rstR-El:93.3%,50.0% was statistically significant (all P 0. 05). Conclusion there are some virulence factors in different degrees of O1 cholera strains in Fujian Province from 1962 to 2005, and the detection rate of Elto gene fragments of all virulence factors is higher than that of paleotypic strains, the difference between rstR and tcpA genes is the most obvious. Compared with rice leaf serotype, Ogawa serotype is easier to integrate the ancient typical ctxB and rstR gene fragments, and the types of ctxB and rstR genes are correlated with the epidemic ability of different serotype cholera strains.
【作者单位】：福建省疾病预防控制中心;福建省人兽共患病研究重点实验室;福建医科大学公共卫生学院教学基地;
【分类号】：R378

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