温暖月份零售带壳牡蛎中副溶血性弧菌的定量研究

为了解温暖月份零售带壳牡蛎中副溶血性弧菌 (VP)的污染情况 ,2 0 0 3年 4～ 8月在福建省福州和厦门两地共收集带壳牡蛎 113份 ,样品分别来自水产品批发市场 (18% ) ,零售市场 (4 6 % )和饭店 (36 % )。采用Vitek鉴定系统和最可能数法进行VP的定量分析。结果显示 ,带壳牡蛎中VP密度的几何均数为 6 0MPN 10 0g ,4 1 6 %的样品VP密度低于 30MPN 10 0g的最低检出限 ,仅厦门2个样品菌量超过 2 4 0 0 0MPN 10 0g。两个地区、不同采样点和不同月份之间样品VP密度的几何均数差别均有统计学意义 (P <0 0 1)。厦门样品污染菌量高于福州 ;批发市场样品菌量最高 ;5月份样品菌量最高 ,为 14 9MPN 10 0g ,而 6～ 8月样品菌量约为 4 0MPN 10 0g。零售环节带壳牡蛎VP的检出率较高。未来应加强对生食海产品中VP污染状况的监测。

Quantitative anlaysis of Vibrio parahaemolyticus in retail shell oysters in the warmer months

Vibrio parahaemolyticus in retail shell oysters were investigated in the warmer months. From April to August 2003,113 oysters in shell were sampled monthly in Fuzhou and Xiamen of Fujian province,China (36% from restaurants;46% from retail markets and 18% from wholesale seafood markets). The V. parahaemolyticus in oyster samples was determined qualitatively and quantitatively by the Vitek identification system and the most probable number technique. The geometric mean V. parahaemolyticus density in retail shell oysters was 60 MPN/100 g,with 41.6% had V. parahaemolyticus densities below the detectable level of 30 MPN/100 g;only two samples from Xiamen were found to harbor V. parahaemolyticus densities exceeding \{24 000 MPN/100 g.\} There were significant differences in the V. parahaemolyticus densities among different regions,sampling sites and months ( P <0.01). Oysters from Xiamen had higher densities of V. parahaemolyticus than did oysters collected from Fuzhou. The highest mean V. parahaemolyticus density was observed in samples from wholesale seafood market. The highest mean V. parahaemolyticus density was observed in samples collected in May (149 MPN/100 g) while approximately 40 MPN/100 g was observed in samples collected in June and August. High frequency of V. parahaemolyticus was detected in retail shell oysters. It is concluded that this organism needs to be intensively monitored and controlled in raw seafoods.