Antibiotic resistance and molecular characteristics of Vibrio cholerae from aquatic products and diarrhea patients in Shaoxing from 2020 to 2021

Abstract

ObjectiveTo investigate the serotype， cholera toxin encoding gene （ctxAB） carying rate， antibiotic resistance and molecular typing of Vibrio cholerae in Shaoxing from 2020 to 2021.MethodsSixty-eight strains were isolated from aquatic products and feces of patients with diarrhea from 2020 to 2021， and serologically classified by glass agglutination method. The ctxAB gene was detected by real-time fluorescence polymerase chain reaction. Microbroth dilution method and pulsed field gel electrophoresis （PFGE） were used for antibiotic sensitivity test and molecular typing of strains， respectively.ResultsOnly three of the 68 strains were O1 serotype Ogawa， and the other 65 strains were non-O1/O139 serogroup. All strains did not detected ctxAB gene. The antibiotic resistance rates to ceftazidime， ceftazidime/avibactam and cotrimoxazole were 45.6%， 38.2% and 36.8%， respectively. All strains were sensitive to tetracycline， tigecycline， azithromycin and amikacin， and 17 strains were resistant to 3 or more antibiotics. PFGE molecular typing of strains digested by Not I showed diversity， and there was a great difference between the aquatic product isolates and the case isolates.ConclusionThe main serogroup of Vibrio cholerae was non-O1/O139 in Shaoxing from 2020 to 2021. The strains did not carry ctxAB gene and were resistant to multiple antibiotics. The molecular characteristics of strains were complex and diverse.

Keywords

• vibrio cholerae
• serotype
• ctxab gene
• antibiotic resistance
• pulsed field gel electrophoresis