Hasan Badrul, Melhus Åsa, Sandegren Linus, Alam Munirul, Olsen Björn
1 Clinical Microbiology and Infectious Medicine, Department of Medical Sciences, Uppsala University , Uppsala, Sweden .
Microb Drug Resist. 2014 Oct;20(5):466-71. doi: 10.1089/mdr.2013.0233. Epub 2014 Apr 30.
The presence and frequency of multiresistant bacteria in wild birds act as indicators of the environmental contamination of antibiotic resistance. To explore the rate of contamination mediated by Escherichia coli, 150 fecal samples from the brown-headed gull (Chroicocephalus brunnicephalus) and 8 water samples from the Bay of Bengal area were collected, cultured, and tested for antibiotic susceptibility. Special attention was paid to extended-spectrum beta-lactamase (ESBL)-producing isolates, which were further characterized genetically. Antibiotic resistance was found in 42.3% (36/85) of the E. coli isolates and multidrug resistance in 11.8%. Isolates from the area with a higher human activity were more resistant than those from an area with a lower level of activity. Most frequent was resistance to ampicillin (29.4%), followed by trimethoprim-sulfamethoxazole (24.7%) and quinolones (22.4%). Carriage of ESBL-producing E. coli was relatively high (17.3%) in the gulls, whereas no ESBL producers were found in the water. All ESBL-producing E. coli isolates, but one, carried bla(CTX-M-15) or bla(CTX-M-15)-like genes. A bla(CTX-M-14)-like enzyme was found as an exception. Gulls from two different colonies shared E. coli clones and harbored the clinically relevant sequence types ST10, ST48, and ST131. The high frequency of antibiotic resistance and ESBL production among E. coli isolates from gulls indicates that the environmental contamination of antibiotic resistance has already gone far on the coastlines of the Bay of Bengal. Considering the limited control over the antibiotic consumption and waste from human activities in Bangladesh, there is no easy solution in sight.
野生鸟类中多重耐药细菌的存在及频率可作为抗生素耐药性环境污染的指标。为探究大肠杆菌介导的污染率，收集了150份棕头鸥（Chroicocephalus brunnicephalus）粪便样本和8份孟加拉湾地区水样，进行培养并检测抗生素敏感性。特别关注产超广谱β-内酰胺酶（ESBL）的分离株，并对其进行进一步基因特征分析。在42.3%（36/85）的大肠杆菌分离株中发现抗生素耐药性，11.8%为多重耐药。来自人类活动较高地区的分离株比活动水平较低地区的分离株耐药性更强。最常见的是对氨苄西林耐药（29.4%），其次是对甲氧苄啶-磺胺甲恶唑耐药（24.7%）和喹诺酮类耐药（22.4%）。海鸥中产ESBL大肠杆菌的携带率相对较高（17.3%），而在水中未发现产ESBL菌。除一株外，所有产ESBL大肠杆菌分离株均携带bla(CTX-M-15)或bla(CTX-M-15)样基因。仅发现一种例外的bla(CTX-M-14)样酶。来自两个不同群落的海鸥共享大肠杆菌克隆，并携带临床相关的序列类型ST10、ST48和ST131。海鸥大肠杆菌分离株中抗生素耐药性和ESBL产生的高频率表明，孟加拉湾海岸线的抗生素耐药性环境污染已相当严重。考虑到孟加拉国对人类活动中抗生素消费和废物的控制有限，目前尚无简单的解决办法。
