E-Poster Presentation Australian Society for Microbiology Annual Scientific Meeting 2021

Population structure and multidrug resistance of non-O1/non-O139 Vibrio cholerae in freshwater rivers in Zhejiang, China (#321)

Yun Luo 1 , Henghui Wang 2 , Jie Liang 3 , Huiqin Qian 4 , Julian Ye 4 , Lixia Chen 2 , Xianqing Yang 3 , Zhongwen Chen 2 , Fei Wang 3 , Sophie Octavia 1 , Michael Payne 1 , Xiaojun Song 5 , Jianmin Jiang 4 , Dazhi Jin 5 6 , Ruiting Lan 1
  1. University of New South Wales, Bondi Junction, NSW, Australia
  2. Jiaxing Center for Disease Control and Prevention, Jiaxing, Zhejiang, China
  3. Jiande Center for Disease Control and Prevention, Hangzhou, Zhejiang, China
  4. Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang, China
  5. Centre of Laboratory Medicine, Zhejiang Provincial People Hospital, People’s Hospital of Hangzhou Medical College, Hangzhou, Zhejiang, China
  6. School of Laboratory Medicine, Hangzhou Medical College, Hangzhou, Zhejiang, China

To understand the environmental reservoir of V. cholerae and their public health significance we surveyed the freshwater samples from rivers in two cities (Jiaxing [JX] and Jiande [JD]) in Zhejiang, China. A total of 26 sampling locations were selected and river water was sampled 456 times from 2015 and 2016 yielding 200 V. cholerae isolates all of which were non-O1/non-O139. The average isolation rate was 47.3% and 39.1% in Jiaxing and Jiande respectively. Antibiotic resistance profiles of the V. cholerae isolates were examined with nonsusceptibility to cefazolin (68.70%, 79/115) being most common, followed by ampicillin (47.83%, 55/115) and imipenem (27.83%, 32/115). Forty-two isolates (36.52%, 42/115) were defined as multidrug resistant (MDR). Virulence gene presence was also determined and the majority of the isolates were positive for toxR (198/200, 99%) and hlyA (196/200, 98%) with few other virulence genes observed. The population structure of the V. cholerae non-O1/non-O139 sampled was examined using multilocus sequence typing (MLST) with 200 isolates assigned to 128 STs and 6 subpopulations. The non-O1/non-O139 V. cholerae population in JX was more varied than in JD. By clonal complexes (CCs), 31 CCs that contained isolates from this study were shared with other parts of China and/or other countries, suggesting widespread presence of some non-O1/non-O139 clones. Drug resistance profiles differed between subpopulations. The findings suggest that non-O1/non-O139 V. cholerae in the freshwater environment is a potential source of human infections. Routine surveillance of non-O1/non-O139 V. cholerae in freshwater rivers will be of importance to public health.