丹东市散发霍乱病例病原学特征及与水体和海(水)产品霍乱弧菌污染间的关系

Pathogenic characteristics of sporadic cholera cases in Dandong City of Liaoning Province and the relationship with Vibrio cholerae polluted water and seafood

目的探讨丹东市2004-2005年散发霍乱病例病原学特征以及与水体和海(水)产品检出霍乱弧菌的关系。方法采用血清学和分子生物学相结合的方法,研究不同血清型、噬菌体—生物型霍乱弧菌生化特性、分子分型、聚类分析以及肠毒素基因携带情况。结果所有噬菌体—生物型为流行株(1b、1d)的霍乱弧菌均为产毒株,肠毒素基因携带率100%,非流行株均不携带肠毒素基因;PFGE分子分型及聚类分析表明病患分离株与水体及海(水)产品分离株之间存在高度遗传相关性。结论丹东地区霍乱弧菌致病力较强,水体及海(水)产品霍乱弧菌污染是导致霍乱发病的关键,且已形成污染—感染的恶性循环。不良卫生习惯和饮食习惯以及忽视就诊,加剧了这一循环,也在很大程度上为霍乱防制和治疗带来了困难。

objective This study was conducted to investigate the pathogenic characteristics of sporadic cholera cases in Dandong City from 2004 to 2005 and the relationship with Vibrio cholerae detected from seawater and seafood. Methods The combination of serological and biochemical tests were applied to work over the biochemical characteristics, molecular typing, cluster analysis and cholera toxin （CTX） gene carrying status of Vibrio cholerae of different serotypes and phage-biotypes. Results All the Vibrio cholerae with the phage-biotype of prevalent strain （lb, ld） were toxin-producing strains with a CTX gene carrying rate of 100 % and none of the non-prevalent strain was found to carry CTX gene. PFGE molecular typing and cluster analysis showed a high genetic association between the strains isolated from the patients and those from the seawater and seafood. Conclusion The vibrio cholerae found in Dandong has high pathogenicity. The V. cholerae pollution of water and seafood is the key to the occurrence of cholera cases, and a vicious circle of pollution-infection has come into being. People＇s unhygienic habits and hesitation in seeking medical care exacerbate this cycle and to a large extent makes it difficult to control and treat cholera.