摘要

       使用从室内和室外环境收集的气溶胶中的定量 PCR 枚举编码四环素抗性和 1 类整合子整合酶的基因。发现集中动物饲养操作 (CAFO) 和人类居住的室内环境（两个诊所和一个无家可归者收容所）是空气传播 tet(X) 和 tet(W) 基因的来源。 CAFO 的空气中 16S rRNA、tet(X) 和 tet(W) 基因浓度比其他采样环境高 10 到 100 倍，并且气溶胶细菌浓度增加与空气中抗性基因浓度增加相关。研究的两个 CAFO 在其气溶胶样本中具有统计学上相似的抗性基因浓度，尽管两次操作之间的抗生素使用明显不同。此外，在距离牲畜作业 2 公里范围内的室外空气中回收了 tet(W) 基因，这表明抗生素抗性基因可能通过气溶胶在局部范围内传播。来自 1 类整合子的整合酶基因 (intI1) 与多药耐药性相关，在 CAFO 中检测到，但在人类居住的室内环境中未检测到，这表明 CAFO 气溶胶可以作为多药耐药性的储存库。总之，我们的结果表明，CAFO 和诊所是雾化抗生素抗性基因的来源，这些基因可能通过空气流动进行传播。

       Genes encoding tetracycline resistance and the integrase of Class 1 integrons were enumerated using quantitative PCR from aerosols collected from indoor and outdoor environments. Concentrated animal feeding operations (CAFOs) and human-occupied indoor environments (two clinics and a homeless shelter) were found to be a source of airborne tet(X) and tet(W) genes. The CAFOs had 10- to 100-times higher concentrations of airborne 16S rRNA, tet(X), and tet(W) genes than other environments sampled, and increased concentrations of aerosolized bacteria correlated with increased concentrations of airborne resistance genes. The two CAFOs studied had statistically similar concentrations of resistance genes in their aerosol samples, even though antibiotic use was markedly different between the two operations. Additionally, tet(W) genes were recovered in outdoor air within 2 km of livestock operations, which suggests that antibiotic resistance genes may be transported via aerosols on local scales. The integrase gene (intI1) from Class 1 integrons, which has been associated with multidrug resistance, was detected in CAFOs but not in human-occupied indoor environments, suggesting that CAFO aerosols could serve as a reservoir of multidrug resistance. In conclusion, our results show that CAFOs and clinics are sources of aerosolized antibiotic resistance genes that can potentially be transported via air movement.

https://pubs.acs.org/doi/abs/10.1021/es400238g