PDF(Pubmed)
Abstract：
Vibrio parahaemolyticus is the leading cause of seafood-associated bacterial gastroenteritis worldwide. Although different studies have focused on its pattern of variation over time, knowledge about the environmental factors driving the dynamics of this pathogen, within the Chilean territory, is still lacking. This study determined the prevalence of total and pathogenic V. parahaemolyticus strains (tdh and/or trh genes) in mussels (Mytilus chilensis) collected from two natural growing areas between 2017 and 2018, using selective agar and PCR analysis. V. parahaemolyticus was detected in 45.6% (93/204) of pooled samples from the Valdivia River Estuary. The pathogenic strains carrying the tdh and/or trh gene were detected in 11.8% (24/204): tdh in 9.8% (20/204), trh in 0.5% (1/204), and 1.5% (3/204) presented both genes. In Reloncaví Fjord, V. parahaemolyticus was detected in 14.4% (30/209) of the samples, pathogenic V. parahaemolyticus carrying the trh gene was detected in 0.5% (1/209) of the samples, while the tdh gene was not detected in the samples from this area. The total count of mauve-purple colonies typical of V. parahaemolyticus on CHROMagar was positively associated by multivariate analysis with area, water temperature, and salinity. Similarly, V. parahaemolyticus detection rates by PCR had a positive correlation with the area and water temperature. The chances of detecting total V. parahaemolyticus in the Valdivia River Estuary are significantly higher than in the Reloncaví Fjord, but inversely, during spring-summer months, the interaction factor between the area and temperature indicated that the chances of detecting V. parahaemolyticus are higher in the Reloncaví Fjord. Interestingly, this period coincides with the season when commercial and natural-growing shellfish are harvested. On the other hand, pathogenic V. parahaemolyticus tdh+ was significantly correlated with an increase of water temperature. These environmental parameters could be used to trigger a warning on potential hazard, which would influence human health and economic losses in aquaculture systems.
摘要：
副溶血性弧菌是全球海产品相关细菌性肠胃炎的主要病因。尽管不同的研究集中在它随时间的变化模式上，了解驱动这种病原体动态的环境因素，在智利领土内，仍然缺乏。这项研究使用选择性琼脂和PCR分析，确定了2017年至2018年从两个自然生长地区收集的贻贝（Mytiluschilensis）中总和致病性副溶血弧菌菌株（tdh和/或trh基因）的患病率。在Valdivia河口的合并样本中，有45.6％（93/204）检测到副溶血弧菌。携带tdh和/或trh基因的致病菌株检出11.8%(24/204):tdh检出9.8%(20/204),trh在0.5%(1/204)，和1.5％（3/204）提出了这两个基因。在Reloncví峡湾，在14.4%(30/209)的样本中检测到副溶血性弧菌，在0.5%(1/209)的样本中检测到携带trh基因的致病性副溶血性弧菌，而该地区的样本中没有检测到tdh基因。通过多变量分析，CHROMagar上典型的副溶血性弧菌的紫红色紫色菌落总数与面积呈正相关，水温,和盐度。同样，PCR检测副溶血性弧菌的检出率与面积和水温呈正相关。在瓦尔迪维亚河口发现总副溶血性弧菌的机会明显高于Reloncaví峡湾，但相反，在春夏季，区域与温度之间的相互作用因子表明，在Reloncavia峡湾中检测副溶血性弧菌的机会更高。有趣的是,这一时期与收获商业和自然生长贝类的季节相吻合。另一方面,致病性副溶血性弧菌tdh与水温升高显着相关。这些环境参数可用于触发潜在危险的警告，这将影响水产养殖系统中的人类健康和经济损失。
