Sambe-Ba Bissoume, Diallo Mamadou H, Seck Abdoulaye, Wane Abdoul A, Constantin de Magny Guillaume, Boye Cheikh S-B, Sow Ahmad I, Gassama-Sow Amy
Unité de Bactériologie Expérimentale, Institut Pasteur DakarDakar, Sénégal.
Laboratoire de Microbiologie Fondamentale et Appliquée, Faculté de Médecine et Pharmacie et d'Odontologie, Université Cheikh Anta DiopDakar, Sénégal.
Front Microbiol. 2017 May 15;8:748. doi: 10.3389/fmicb.2017.00748. eCollection 2017.
O1 is the causative agent of cholera with classical and El Tor, two well-established biotypes. In last 20 years, hybrid strains of classical and El Tor and variant El Tor which carry classical B have emerged worldwide. In 2004-2005, Senegal experienced major cholera epidemic with a number of cases totalling more than 31719 with approximately 458 fatal outcomes (CFR, 1.44%). In this retrospective study, fifty isolates out of a total of 403 biotype El Tor serovar Ogawa isolates from all areas in Senegal during the 2004-2005 cholera outbreak were randomly selected. Isolates were characterized using phenotypic and genotypic methods. The analysis of antibiotic resistance patterns revealed the predominance of the S-Su-TCY-Tsu phenotype (90% of isolates). The molecular characterization of antibiotic resistance revealed the presence of the SXT element, a self-transmissible chromosomally integrating element in all isolates. Most of isolates had an intact virulence cassette (86%) (, , genes). All isolates tested gave amplification with primers for classical CT, and 10/50 (20%) of isolates carried classical and El Tor B. The study reveals the presence of atypical O1 El Tor during cholera outbreak in Senegal in 2004-2005.
O1是霍乱的病原体，有经典生物型和埃尔托生物型这两种公认的生物型。在过去20年中，携带经典B抗原的经典生物型与埃尔托生物型的杂交菌株以及变异埃尔托生物型在全球出现。2004 - 2005年，塞内加尔经历了大规模霍乱疫情，病例总数超过31719例，约458例死亡（病死率1.44%）。在这项回顾性研究中，从2004 - 2005年霍乱疫情期间塞内加尔所有地区的403株埃尔托生物型小川血清型分离株中随机选取了50株。使用表型和基因型方法对分离株进行了特征分析。抗生素耐药模式分析显示S - Su - TCY - Tsu表型占主导（90%的分离株）。抗生素耐药性的分子特征分析显示所有分离株中均存在SXT元件，这是一种可自我传递的染色体整合元件。大多数分离株具有完整的毒力盒（86%）（ctxA、ctxB、tcpA基因）。所有检测的分离株用经典霍乱毒素引物均能扩增，10/50（20%）的分离株携带经典和埃尔托B抗原。该研究揭示了2004 - 2005年塞内加尔霍乱疫情期间存在非典型O1埃尔托生物型。
