Motes M L, DePaola A, Cook D W, Veazey J E, Hunsucker J C, Garthright W E, Blodgett R J, Chirtel S J
Gulf Coast Seafood Laboratory, U.S. Food and Drug Administration, Dauphin Island, Alabama 36528-0158, USA.
Appl Environ Microbiol. 1998 Apr;64(4):1459-65. doi: 10.1128/AEM.64.4.1459-1465.1998.
This study investigated the temperature and salinity parameters associated with waters and oysters linked to food-borne Vibrio vulnificus infections. V. vulnificus was enumerated in oysters collected at three northern Gulf Coast sites and two Atlantic Coast sites from July 1994 through September 1995. Two of these sites, Black Bay, La., and Apalachicola Bay, Fla., are the source of the majority of the oysters implicated in V. vulnificus cases. Oysters in all Gulf Coast sites exhibited a similar seasonal distribution of V. vulnificus: a consistently large number (median concentration, 2,300 organisms [most probable number] per g of oyster meat) from May through October followed by a gradual reduction during November and December to < or = 10 per g, where it remained from January through mid-March, and a sharp increase in late March and April to summer levels. V. vulnificus was undetectable (< 3 per g) in oysters from the North and South Carolina sites for most of the year. An exception occurred when a late-summer flood caused a drop in salinity in the North Carolina estuary, apparently causing V. vulnificus numbers to increase briefly to Gulf Coast levels. At Gulf Coast sites, V. vulnificus numbers increased with water temperatures up to 26 degrees C and were constant at higher temperatures. High V. vulnificus levels (> 10(3) per g) were typically found in oysters from intermediate salinities (5 to 25 ppt). Smaller V. vulnificus numbers (< 10(2) per g) were found at salinities above 28 ppt, typical of Atlantic Coast sites. On 11 occasions oysters were sampled at times and locations near the source of oysters implicated in 13 V. vulnificus cases; the V. vulnificus levels and environmental parameters associated with these samples were consistent with those of other study samples collected from the Gulf Coast from April through November. These findings suggest that the hazard of V. vulnificus infection is not limited to brief periods of unusual abundance of V. vulnificus in Gulf Coast oysters or to environmental conditions that are unusual to Gulf Coast estuaries.
本研究调查了与食源性创伤弧菌感染相关的水体及牡蛎的温度和盐度参数。在1994年7月至1995年9月期间，从墨西哥湾北部海岸的3个地点和大西洋海岸的2个地点采集牡蛎，对其中的创伤弧菌进行计数。这些地点中的两个，即路易斯安那州的布莱克湾和佛罗里达州的阿巴拉契科拉湾，是大多数与创伤弧菌病例相关的牡蛎的来源地。墨西哥湾沿岸所有地点的牡蛎中创伤弧菌的季节性分布相似：从5月到10月数量一直很多（每克牡蛎肉的中位数浓度为2300个菌[最可能数]），随后在11月和12月逐渐减少至每克≤10个，1月至3月中旬保持在这个水平，3月下旬和4月急剧增加至夏季水平。北卡罗来纳州和南卡罗来纳州的牡蛎在一年中的大部分时间里都检测不到创伤弧菌（<每克3个）。但有一个例外，夏末的一次洪水导致北卡罗来纳州河口盐度下降，显然使创伤弧菌数量短暂增加至墨西哥湾沿岸的水平。在墨西哥湾沿岸的地点，创伤弧菌数量随水温升高至26℃而增加，在更高水温下保持稳定。创伤弧菌水平较高（>每克10³个）通常见于盐度中等（5至25ppt）的牡蛎中。在盐度高于28ppt（大西洋沿岸地点的典型盐度）时，创伤弧菌数量较少（<每克10²个）。有11次在与13例创伤弧菌病例相关的牡蛎来源地附近的时间和地点采集牡蛎样本；与这些样本相关的创伤弧菌水平和环境参数与4月至11月从墨西哥湾沿岸采集的其他研究样本一致。这些发现表明，创伤弧菌感染的风险不仅限于墨西哥湾沿岸牡蛎中创伤弧菌短暂异常大量存在的时期，也不限于墨西哥湾沿岸河口不寻常的环境条件。
