豫北地区主要淡水鱼类感染嗜水气单胞菌的流行病学调查

摘要

对豫北地区嗜水气单胞菌引起的细菌性败血病进行流行病学调查，分离鉴定致病性嗜水气单胞菌菌株，并对致病性嗜水气单胞菌菌株进行毒力验证和药敏试验。采集4个养殖场病鱼标本及水样，每月进行流行病学调查，利用生理生化及分子生物学方法检测嗜水气单胞菌的分布状况。结果显示，筛选出52株为嗜水气单胞菌，其中32株为致病性嗜水气单胞菌，20株为非致病性嗜水气单胞菌，且致病性嗜水气单胞菌主要分布在7—9月份，毒力验证试验表明，32株致病性菌株的毒力大小差异明显，筛选出强毒株XDMG（4），为后期试验的疫苗株做准备；药敏试验表明，不同菌株对同一种药物的药敏结果不同，但大部分药物的药敏结果基本一致，70％以上的致病性菌株对头孢哌酮、氟本尼考、菌必治、阿米卡星等抗菌药物表现为高度敏感，对青霉素类药物表现为高度耐药性，耐药率达100％，对氨基糖苷类（不包括阿米卡星）、磺胺类、四环素等药物呈现不同程度的耐药性，具有多重耐药性。本试验旨在丰富本地区的鱼类细菌性败血病的病原资料，并为该菌引起的人类疾病的防控提供科学依据。%To investigate the epidemiology of bacterial septicemia outbreak in fish ,Aeromonas hydrophila were isolated and identified from the northern regions of Henan Province ,China ,and the virulence and drug sensitive characteristics of pathogenic strains were verified .The diseased fish samples and water sam‐ples were collected from 4 fish cultured area in the northern regions of Henan Province .Epidemiological investigation were performed once a month ,and the distribution of A .hydrophila were detected by physi‐ological and biochemical and molecular biological methods .A total of 52 A .hydrophila strains ,32 patho‐genic strains ,20 non pathogenic strains ,were isolated and the pathogenic strains were primary distributed from July to September .Virulence experiment showed that there were different toxicities among 32 patho‐genic strains ,through which the highest virulent strain XDMG (4) were screened ,which will be as the vaccine strain for further experiments .Drug resistance indicated that differenct sensitivity to the same drug varried with different strains ,but most drug resistance was consistent .About 70% pathogenic strains were highly sensitive to Cefoperazone ,Florfenicol ,Ceftriaxone Sodium and Amikacin ,highly resistant to penicillin drugs ,with resistance rate of 100% ,and certain extent resistance to Aminoglycosides (except Amikacin) ,Sulfonamides ,and Tetracycline .The different strains showed differences in drug resistance . The findings would help enrich in epidemic data of the bacteria septicemia in this region ,and provide scien‐tific theoretical basis for human disease caused by A .hydrophila .