title: Identification of virulence factors in  Vibrio cholerae  isolated from Iraq during the 2007-2009 outbreak.
abstract: Thousands of people were infected with  Vibrio cholerae  during the outbreak in Iraq in 2007-2009. Vibrio cholerae was shown to be variable in its content of virulence determinants and in its antibiotic sensitivity. This study was designed to isolate and characterize clinical and environmental V. cholerae isolates and to determine  antibiotic sensitivity, enzyme and toxin production,  and the presence of virulence genes. Eighty clinical and five environmental bacterial isolates were collected and diagnosed by subjecting them to microscopic, biochemical, serological, and molecular analysis. The results revealed that 55% of clinical isolates belonged to the Inaba serotype, 32.5% to the Ogawa serotypes, and 12.5% to the Non-O1 serotype. All environmental V. cholerae isolates belonged to the Non-O1 serotype. All environmental isolates were sensitive to all examined antimicrobial agents, while all clinical isolates showed a high sensitivity (100%) to ampicillin, gentamicin, cephalothin, tetracycline, erythromycin, and ciprofloxacin, and a high resistance (97.5%) to co-trimoxazole, nalidixic acid, and chloramphenicol. It was found that all V. cholerae (O1) isolates were resistant to the Vibrio static O129 and all Non-O1 V. cholerae isolates were sensitive to the Vibrio static O129. All clinical and environmental isolates produced hemolysin (100%) and lecithinase (100%), while they showed various production rates of protease (90% of clinical and 60% of environmental) and lipase (50% of clinical and 20% of environmental). The ompW gene was amplified in all the clinical and environmental V. cholerae isolates, but not in other related and nonrelated bacteria. Multiplex PCR analysis showed that the toxR gene was amplified in all clinical and environmental isolates, while ctxA, ctxB, tcpA genes were amplified only in clinical (O1) isolates. This study indicates the differences in the production of some enzymes and toxins and in the content of virulence genes between clinical and environmental isolates in Iraq during the outbreak (2007-2009).
authors: Biology Department, College of Science, Almustansyria University, Baghdad, Iraq.
authors: Tahreer Hadi
authors: TH
authors: Saleh
authors: Majeed Arsheed
authors: MA
authors: Sabbah
authors: Kifah A
authors: KA
authors: Jasem
authors: Zuhair N
authors: ZN
authors: Hammad
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002771:Cholera / Q000453:epidemiology / Q000382:microbiology*; D002772:Cholera Toxin / Q000235:genetics / Q000378:metabolism / Q000633:toxicity; D004196:Disease Outbreaks; D004352:Drug Resistance, Microbial; D004783:Environmental Microbiology; D006460:Hemolysin Proteins / Q000235:genetics; D006801:Humans; D007493:Iraq; D008826:Microbial Sensitivity Tests; D060885:Multiplex Polymerase Chain Reaction; D016133:Polymerase Chain Reaction; D011817:Rabbits; D012867:Skin / Q000187:drug effects; D014734:Vibrio cholerae / Q000145:classification / Q000187:drug effects / Q000235:genetics* / Q000472:pathogenicity*; D037521:Virulence Factors / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D006460:Hemolysin Proteins; D037521:Virulence Factors; D002772:Cholera Toxin