Characterisation of virulence factors in Vibrio cholerae isolates from the recent cholera outbreak in Senegal (Sub-Saharan Africa)

Abstract number: 1733_1335

Diallo M.H., Sow A.I., Boye C.S., Aidara Kane A., Gassama Sow A.

Cholera is an epidemic diarrhoeal disease generally caused by toxigenic O1 or O139 Vibrio cholerae. Senegal has in last two years experienced major cholera epidemic with a number of cases totalling more than 23, 325 with approximately 303 fatal outcomes. The most important virulence factor produced by V. cholerae is cholera toxin (CT) encoded by ctx gene. The genes encoding zonula occludens toxin (Zot) and accessory enterotoxin (Ace) are located upstream to the ctx gene on a dynamic region of V. cholerae chromosome termed virulence cassette. Toxin co-regulated pilus (Tcp) is a colonisation factor. The aim of our study is to characterise virulence genes among 50 of O1 clinical V. cholerae isolates from the last V. cholerae outbreak occurring in 2004–2005 in Senegal. Virulence genes were characterised by polymerase chain reaction (PCR) using specifics primers. Ctx, zot, ace genes were present respectively in 98%, 88%, and 92%. Most of V. cholerae isolates have an intact virulence cassette (86%) (ctx, zot, ace genes). This virulence cassette is absent in one isolate; it was deleted (zot, ace genes) in two isolates. Both ZOT and ACE play synergetic role with CT in the epidemic V. cholerae toxicity. Strains did not harbour Tcp gene.

Session Details

Date: 31/03/2007
Time: 00:00-00:00
Session name: European Society of Clinical Microbiology and Infectious Diseases
Location: ICC, Munich, Germany
Presentation type:
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