Blast score ratio (BSR) results.

Northern Cameroon in Central Africa has experienced recurring cholera outbreaks despite ongoing efforts to control the disease. While most cholera studies focus on O1 pandemic Vibrio cholerae strains, non-O1/O139 strains are increasingly recognized for their infection potential and dynamic relationships with O1 strains during outbreaks. Here we explore the genetic diversity and phylogenetic relationships of non-O1/O139 V. cholerae (NOVC) isolated from environmental water sources in Northern Cameroon. These NOVC strains show significant genetic diversity and virulence potential. They are closely related to environmental strains from Kenya and clinical strains from Argentina and Haiti, suggesting transmissions across countries and continents, likely facilitated by human carriers. The highly conserved tcpA gene found in some strains from Cameroon is closely related to the tcpA O1 Classical type, suggesting direct or indirect genetic interactions between these environmental NOVC strains and pandemic strains. Our findings underscore the importance of environmental surveillance and further studies of NOVC strains to better understand cholera outbreaks.

中非喀麦隆北部地区虽持续开展霍乱防控工作，但仍反复暴发霍乱疫情。当前多数霍乱研究均聚焦于O1群大流行霍乱弧菌（Vibrio cholerae）菌株，而非O1/O139群菌株的致病潜力及其在疫情暴发期间与O1群菌株的动态关联，正日益受到学界关注。本研究针对从喀麦隆北部地区环境水源中分离得到的非O1/O139群霍乱弧菌（non-O1/O139 V. cholerae，简称NOVC），探究其遗传多样性与系统发育关系。结果显示，该类NOVC菌株具有显著的遗传多样性与毒力潜力。它们与肯尼亚的环境分离株、阿根廷及海地的临床分离株亲缘关系较近，提示菌株可跨越国界与大洲传播，人类携带者或为传播的重要介导因素。喀麦隆部分菌株中携带的高度保守tcpA基因，与O1群古典生物型的tcpA基因亲缘关系密切，表明这些环境NOVC菌株与大流行菌株之间存在直接或间接的遗传互作。本研究结果凸显了开展环境监测以及对NOVC菌株开展深入研究的重要性，有助于更全面地理解霍乱疫情的暴发机制。