Centre for Microbiology (KEMRI-CMR), Kenya Medical Research Institute, Nairobi, Kenya.
The University of Nairobi, Department of Veterinary, Pathology, Microbiology and Parasitology (UoN-Kenya).
PLoS One. 2024 Nov 14;19(11):e0310026. doi: 10.1371/journal.pone.0310026. eCollection 2024.
Carbapenem-resistant bacteria (CRB) present a significant global public health concern. Sub-Saharan Africa has borne a heavy burden of CRB with a reported prevalence of up to 60% in some patient populations. es in Africa focus on clinical CRB isolates, with limited data on their spread in the natural environment. Therefore, the purpose of this study was to report the recovery of CRB from Nairobi River surface waters and nearby anthropogenic and zoonotic sources in Nairobi County, Kenya. A total of 336 CRB were recovered from 336 (250 mL) samples, with 230 of the samples (68.5%) producing one or more CRB isolates. CRB were recovered most commonly from untreated sewage influent (100% of 36 samples; 79 total isolates), treated effluent (93% of 118 samples; 116 total isolates), Nairobi River surface waters upstream (100% of 36 samples; 57 total isolates), downstream (100% of 36 samples; 45 total isolates), and way downstream from the wastewater treatment plant (73% of 11 samples; 19 total isolates), slaughterhouse effluent discharges 1.5%, (5/336), animal contact areas 0.9%, (3/336), a manhole sewer from the affluent neighborhood of Karen at 2.7%, (9/336) respectively. The CRB included Escherichia coli (158, 47%), Klebsiella pneumoniae (74, 22%), and Enterobacter spp (43, 13%). Aeromonas spp (29, 9%) Acinetobacter baumannii (12, 3.6%), Citrobacter freundii (7, 2.1%), Pseudomonas aeruginosa (5, 1.5%) and other species (8, 2.4%). CRB genotypes included blaNDM (246, 73.2%), blaKPC (40, 12%), blaVIM (51, 15.2%), blaOXA-48-like (65, 19.3%), blaIMP (15, 4.5%), and blaGES (7, 2.1%). Sixty-nine of the CRB isolates (20.5%) harbored multiple carbapenemase-encoding genes. Our results indicate that clinically important CRB are commonly present in Nairobi River surface water and from nearby wastewater and livestock sources. These pose an important public health threat that requires urgent intervention strategies and additional investigation.
耐碳青霉烯类细菌（CRB）对全球公共卫生构成重大威胁。撒哈拉以南非洲地区一直承受着 CRB 的沉重负担，据报道，一些患者群体中的流行率高达 60%。非洲的研究主要集中在临床 CRB 分离株上，而关于它们在自然环境中的传播的数据有限。因此，本研究旨在报告从肯尼亚内罗毕县内罗毕河地表水以及附近人为和动物源中回收 CRB 的情况。从 336 份（250 毫升）样本中回收了 336 株 CRB，其中 230 份样本（68.5%）产生了一株或多株 CRB 分离株。CRB 最常从未经处理的污水进水（36 个样本中的 100%；79 株总分离株）、处理后的污水（118 个样本中的 93%；116 株总分离株）、内罗毕河地表水上游（36 个样本中的 100%；57 株总分离株）、下游（36 个样本中的 100%；45 株总分离株）以及从废水处理厂下游（11 个样本中的 73%；19 株总分离株）回收，屠宰场污水排放占 1.5%（336 个中的 5 个），动物接触区占 0.9%（336 个中的 3 个），从富人区 Karen 的一个沙井下水道回收占 2.7%（336 个中的 9 个）。CRB 包括大肠杆菌（158 株，47%）、肺炎克雷伯菌（74 株，22%）和肠杆菌属（43 株，13%）。气单胞菌属（29 株，9%）鲍曼不动杆菌（12 株，3.6%）、弗氏柠檬酸杆菌（7 株，2.1%）、铜绿假单胞菌（5 株，1.5%）和其他种属（8 株，2.4%）。CRB 基因型包括 blaNDM（246 株，73.2%）、blaKPC（40 株，12%）、blaVIM（51 株，15.2%）、blaOXA-48 样（65 株，19.3%）、blaIMP（15 株，4.5%）和 blaGES（7 株，2.1%）。69 株 CRB 分离株（20.5%）携带多种碳青霉烯酶编码基因。我们的结果表明，临床上重要的 CRB 通常存在于内罗毕河地表水以及附近的废水和牲畜源中。这对公共卫生构成了重大威胁，需要采取紧急干预策略和进一步调查。
