Distribution of antibiotic resistance genes in marine water and sediments in aquaculture areas in Khanh Hoa, Vietnam

Abstract

The emergence of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) poses significant risks to ecological security and human health. Coastal areas affected by urban and aquaculture activities serve as critical reservoirs for pollutants, including ARGs. However, the data on the abundance and distribution of ARGs in marine sediments impacted by aquaculture activities in the East Sea, Vietnam, remain limited. This study investigated the distribution of ARGs across four aquaculture areas in the East Sea of Khanh Hoa province, Vietnam. The results revealed that sulfonamide-resistant genes, sul1and sul2, were present at all sampling sites (100%), with abundance ranging from 2.4 × 102to 2.0 × 105copies/ml in seawater and from 2.0 × 105to 2.57 × 107copies/g in sediments. Tetracycline-resistant genes, including tetQ, tetM, and tetX, were detected at most sampling sites, with abundances ranging from 1.29 × 101to 6.16 × 106copies/ml in seawater and from 1.64 × 104to 1.04 × 108copies/g in sediments. The vancomycin-resistant gene (vanA)exhibited significant abundance, ranging from 1.38 × 103to 3.22 × 104copies/ml in seawater and from 1.14 × 106to 1.9 × 107copies/g in sediments. Finally, integron class 1 (intI1) was detected at all sampling sites (100%) in both seawater and sediments, with abundances up to 6.86 × 105copies/ml in seawater and 2.06 × 108copies/g in sediments. Given aquaculture's significant role in Vietnam's economic growth, implementing effective technologies and national policies to manage and mitigate antimicrobial resistance in aquaculture environments is crucial