Kavai Susan Mutile, Oyugi Julius, Mbae Cecilia, Wairimu Celestine, Kering Kelvin, Kebenei Collins, Muturi Peter, Omulo Sylvia, Kariuki Samuel
Centre for Microbiology Research, Kenya Medical Research Institute, Nairobi, Kenya.
Department of Medical Microbiology and Immunology, University of Nairobi, Kenya.
Int J Clin Microbiol. 2024;1(3):18-27. doi: 10.14302/issn.2690-4721.ijcm-24-5195. Epub 2024 Sep 16.
The persistence of multidrug-resistant (MDR) Typhi (. Typhi) is a challenge especially in regions where typhoid is endemic. Surveillance of circulating genotypes of MDR . Typhi is crucial in typhoid acute cases and carriers. This study aimed to investigate genotypic diversity of . Typhi from symptomatic and asymptomatic children in endemic settings in Nairobi, Kenya. Symptomatic and asymptomatic individuals' ≤ 16 years were recruited at four health facilities and tested for typhoid through stool cultures. The . Typhi isolates were subjected to antibiotic susceptibility testing to investigate multidrug resistance. The MDR . Typhi isolates' DNA was extracted and illumina sequenced. Raw reads were assembled and analyzed by pathogen-watch. From the 90 sequenced isolates, 60 (67%) were confirmed to be . Typhi (sequence Type 1 and genotype 4.3.1). Out of the 60 . Typhi strains; 39 (65%) had plasmids, from these 38 (97%) had plasmids alone. Out of the 60, 59 (98%) . Typhi isolates had . Point mutations conferring reduced susceptibility to quinolones were detected in 42 (70%) of . Typhi isolates, from these; 14 (33%) had , and 28 (67%) genes, respectively. This study reports 4.3.1 (H58) as the most dominant . Typhi genotype responsible for spread of MDR phenotypes carried on plasmids. Presence of MDR . Typhi with resistance genes such as and reduced susceptibility to ciprofloxacin especially among asymptomatic individuals, reiterates the need for use of typhoid conjugate vaccine among vulnerable children as a control and prevention measure against typhoid.
多重耐药伤寒杆菌（MDR Typhi）的持续存在是一项挑战，尤其在伤寒流行地区。监测MDR Typhi的流行基因型对于伤寒急性病例和携带者至关重要。本研究旨在调查肯尼亚内罗毕伤寒流行地区有症状和无症状儿童中Typhi的基因型多样性。在四个卫生机构招募了16岁及以下的有症状和无症状个体，并通过粪便培养检测伤寒。对Typhi分离株进行抗生素敏感性测试以调查多重耐药性。提取MDR Typhi分离株的DNA并进行Illumina测序。原始读数由pathogen-watch进行组装和分析。在90个测序分离株中，60个（67%）被确认为Typhi（序列型1和基因型4.3.1）。在60株Typhi菌株中；39个（65%）有质粒，其中38个（97%）仅有质粒。在60个中，59个（98%）Typhi分离株有……在42个（70%）Typhi分离株中检测到赋予对喹诺酮类药物敏感性降低的点突变，其中；14个（33%）有……基因，28个（67%）有……基因。本研究报告4.3.1（H58）是导致MDR表型通过质粒传播的最主要Typhi基因型。MDR Typhi存在耐药基因如……且对环丙沙星敏感性降低，尤其是在无症状个体中，这再次强调了在易感染儿童中使用伤寒结合疫苗作为控制和预防伤寒措施的必要性。
