Distribution characteristics of pathogenic Vibrio in estuary of eastern coastal rivers in China.

Objective To analyze the distribution of Vibrio in China's coastal rivers and the differences of Vibrio species in different seasons, so as to provide data support for the formulation of environmental detection strategy of pathogenic Vibrio. Methods In August 2019 and January 2020, 2 rivers were selected from 4 monitored cities in Bohai Sea, Yellow Sea, East China Sea and South China Sea, respectively. Water samples were collected at the estuary for isolation and culture of Vibrio. 30 suspected Vibrio colonies were selected from each water sample and identified by microbial mass spectrometer. The distribution characteristics of Vibrio in different sea areas and different seasons were analyzed. Results In Yantai city of Shandong province, Cixi city of Zhejiang province, Cangzhou city of Hebei province, and Fangchenggang city of Guangxi autonomous region, the 32 water samples collected from the four representative cities, 960 strains got from the separation and purification, by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) technical appraisal, in the end, 562 strains of Vibrio were identified, including 211 strains of Vibrio parahaemolyticus (22.0%), 172 strains of Vibrio cholerae (17.9%), 124 strains of Vibrio alginolyticus (12.9%), and 55 strains (5.7%) of the other 8 species. There were significant differences in the distribution of dominant Vibrio in the four sea areas. Vibrio cholerae was dominant in the Yellow Sea (Yantai, Shandong) and the East China Sea (Cixi, Zhejiang), Vibrio parahaemolyticus and Vibrio alginolyticus were dominant in the Bohai Sea (Cangzhou, Hebei), and Vibrio parahaemolyticus was dominant in the South China Sea (Fangchenggang, Guangxi). The dominant strain of Vibrio isolated in summer was Vibrio cholerae (148 strains), accounting for 30.8% of all Vibrio isolated in this season. The dominant strain of Vibrioisolated in winter was Vibrio alginolyticus, a total of 65 strains, accounting for 13.5% of the total Vibrio isolated in the season. There was significant difference in the distribution of dominant Vibrio isolated in summer and winter. Conclusion The distribution of Vibrio in estuaries of rivers in the eastern coastal areas of China is different in sea areas and seasons. [ABSTRACT FROM AUTHOR]