Pathogenic vibrios. Vibrio cholerae Pathogenic vibrios. Vibrio cholerae. Laboratory diagnostics, treatment and prophylaxis of cholera. Vinnitsa National Pirogov Memorial Medical University / Department of microbiology

TAXONOMIC POSITION OF THE PATHOGENIC VIBRIOS Family Vibrionaceae Genus Vibrio Medical important species: V.cholerae V.parahaemolyticus V.vulnificus V.alginolyticus

Classification of the vibrios Biochemical classification by Heiberg (1934) Serological classification

VIBRIO CHOLERAE

Cultural characteristics The cholera vibrions is strongly aerobic Growth is better in an alkaline medium the range of pH being 6.4-9.6 (optimum 8.2) Special media: Alkaline peptone water at pH 8.6; Monsur's taurocholate tellurite peptone water at pH 9.2. Alkaline bile salt agar (BSA) pH 8.2.

Classification of the V. cholerae Biovars: V. cholerae b/v classical V. cholerae b/v El-Tor Serotypes: Ogawa (AB) Inaba (AC) Hikojima (ABC)

Distinguishing features of biovars Tests b/v classical b/v El Tor Agglutination of fowl erythrocytes - + Lysis of sheep erythrocytes Growth in the presence of polymixin B Sensitivity to phages Mukerjee`s group IV phage (C) Mukerjee`s group V phage (El -Tor) Acetoin production in the Voges-Proskauer test

Factors of virulence Exotoxin (choleragen, cholera enterotoxin, cholera toxin, CT, or CTX) Endotoxin. Adherence factors (pili) Proteolytic enzymes (gelatinase, mucinase)

Epidemiology and pathogenesis Infection is acquired through fecally contaminated water or food. Clinical forms: Enteritis Gastroenteritis Choleric algid Choleric coma (severe dehydration)

Laboratory diagnosis Rapid tests Microscopy Bacteriological method Serology

Prophylaxis General measures Specific measures

Vibrio cholerae