We evaluated the occurrence of antibiotic-resistant bacteria, antibiotic-resistant gene, and metal concentration in a tropical river of Sri Lanka as a pre-emptive effort to understand the seasonal impact on their prevalence. Resistance for norfloxacin, ciprofloxacin, levofloxacin, kanamycin monosulfate (KM), tetracycline (TC), and sulfamethoxazole (ST) was measured with Kirby–Bauer disc diffusion method. The prevalence of Escherichia coli ranged from 10 to 27 CFU (colony-forming unit) ml⁻¹ in Kelani River in Sri Lanka, and most of the E. coli isolates were resistant to more than one antibiotic. However, the resistance for TC and ST was much higher than other antibiotics. We found that the resistance percentage for older antibiotics like TC and ST was higher than the newer antibiotics. We detected genes that confer resistance to TCs, sulfonamides, β-lactams, and fluoroquinolones. Seasonal variation in the resistance of fluoroquinolones was much higher than the non-fluoroquinolones, but the effect was antagonistic. Overall, the significant seasonal variations imply the importance of mixed source and environmental conditions for development and transmission of antibiotic resistance.

为了了解季节性变化对其流行的影响，我们做出了先发制人的努力，评估了斯里兰卡热带河流中抗生素抗性细菌，抗生素抗性基因和金属的浓度。用Kirby-Bauer纸片扩散法测量对诺氟沙星，环丙沙星，左氧氟沙星，卡那霉素单硫酸盐（KM），四环素（TC）和磺胺甲恶唑（ST）的耐药性。的患病率大肠杆菌范围从10到27 CFU（菌落形成单位）毫升^-1在Kelani河在斯里兰卡，大多数的大肠杆菌分离株对一种以上的抗生素有抗药性。但是，对TC和ST的耐药性远高于其他抗生素。我们发现，较老的抗生素（如TC和ST）的抗药性百分比高于较新的抗生素。我们检测到对TC，磺酰胺，β-内酰胺和氟喹诺酮类药物具有抗性的基因。氟喹诺酮类药物耐药性的季节性变化远高于非氟喹诺酮类药物，但这种作用具有拮抗作用。总体而言，明显的季节性变化意味着混合来源和环境条件对于发展和传播抗生素耐药性的重要性。