Serovar distribution and antimicrobial susceptibility of nontyphoidal Salmonella enterica in the water environment in An Giang province in 2020

Abstract

The objectives of this study were to determine the presence, serovar distribution, and antibiotic susceptibility of Salmonella enterica in the types of water samples collected in An Giang province in 2020. The cross-sectional study was conducted on 126 samples of river water, canal water, domestic water and ice water collected in An Phu district, An Giang province in 2020. Salmonella enterica sub. enterica was isolated from 15.7% (11/70), 25.0% (7/28) and 14.3% (4/28) of river and canal water, domestic water, and ice water samples, respectively. A  total of 22 Salmonella strains obtained from the 22 positive samples, of which 9 serovars were identified by the combination of slide agglutination test and multiplex PCR targeted H antigen gene. The serovar Blockley (45.5%, 10/22) was most prevalent, followed by Mim and Infantis (13.6%, 3/22 each). Disc diffusion method (exception: E-test for ciprofloxacin) determined the resistant strains to ciprofloxacin (13.6%, 3/22) and ceftriaxone (23.3%, 6/22), which are the drugs of choice for the treatment of Salmonella infection. Multi-drug resistant Salmonella isolates were commonly found (31.8%, 7/22). The presence of strains of Salmonella enterica sub. enterica in the water environment and their antibiotic resistance is a matter of concern for public health.