Investigation on the antibiotic-resistance E.coli in Wenyu river in Beijing

The occurrence of antibiotic-resistance E.coli to four classes of antibiotics including ampicillin, tetracycline, sulfonamide (sulfamethoxazole-trimemoprim) and levofloxacin in Wenyu river in Beijing was investigated by using membrane filter method with E.coli chromogenic culture media. In Wenyu river basin, the total number of E.coli was 10³-10⁷cell/L and the number of antibiotic-resistance E.coli was 0-10⁶ cell/L. The antibiotic-resistance rates to ampicillin, tetracycline, and sulfonamide were 10%-35%, 5%-25%, 10%-35% respectively; while the antibiotic-resistance rate of levofloxacin which was recently using in hospital was lowered than 15%. At the sampling point influenced by the fishery discharge, the number of antibiotic-resistance E.coli to tetracycline was higher markedly than those of resistance E.coli to other antibiotics, while the highest levofloxacin-resistance rates could be inferred having source of human discharge.