Department of Microbiology and Ecology, Faculty of Biology, University of Valencia, Valencia, Spain.
J Fish Dis. 2010 May;33(5):383-90. doi: 10.1111/j.1365-2761.2009.01130.x. Epub 2010 Feb 12.
Vibrio vulnificus biotype 2 is subdivided into two main serovars, serovar E, able to infect fish and humans, and serovar A, only virulent for fish. Serovar E emerged in 1976 as the causative agent of a haemorrhagic septicaemia (warm-water vibriosis) affecting eels cultured in brackish water. Serovar A emerged in 2000 in freshwater-cultured eels vaccinated against serovar E, causing warm-water vibriosis with fish showing a haemorrhagic intestine as the main differential sign. The aim of the present work was to compare the disease caused by both serovars in terms of transmission routes, portals of entry and host range. Results of bath, patch-contact and oral-anal challenges demonstrated that both serovars spread through water and infect healthy eels, serovar A entering mainly by the anus and serovar E by the gills. The course of the disease under laboratory conditions was similar for both serovars in terms of transmission and dependence of degree of virulence on water parameters (temperature and salinity). However, the decrease in degree of virulence in fresh water was significantly greater in serovar E than in serovar A. Finally, both serovars proved pathogenic for tilapia, sea bass and rainbow trout, but not for sea bream, with significant differences in degree of virulence only in rainbow trout. In conclusion, serovar A seems to represent a new antigenic form of V. vulnificus biotype 2 with an unusual portal of entry and is better adapted to fresh water than serovar E.
创伤弧菌生物型 2 分为两个主要血清型，血清型 E 能够感染鱼类和人类，血清型 A 仅对鱼类具有毒性。血清型 E 于 1976 年出现，是导致在半咸水养殖的鳗鱼中发生出血性败血症（温水弧菌病）的病原体。血清型 A 于 2000 年在淡水养殖的、针对血清型 E 进行疫苗接种的鳗鱼中出现，导致出现温水弧菌病，鱼类的主要鉴别特征是肠道出血。本研究旨在比较两种血清型引起的疾病在传播途径、入侵门户和宿主范围方面的差异。水浴、贴敷接触和口服感染挑战的结果表明，两种血清型均可通过水传播并感染健康的鳗鱼，血清型 A 主要通过肛门进入，血清型 E 则通过鳃进入。在实验室条件下，两种血清型的疾病传播过程和对水参数（温度和盐度）的依赖程度相似。然而，在淡水环境中，血清型 E 的毒力下降程度明显大于血清型 A。最后，两种血清型均对罗非鱼、欧洲鲈鱼和虹鳟鱼具有致病性，但对真鲷没有致病性，仅在虹鳟鱼中存在毒力的显著差异。总之，血清型 A 似乎代表了创伤弧菌生物型 2 的一种新的抗原形式，具有不同寻常的入侵门户，并且比血清型 E 更适应淡水环境。
