Improved method, using staphylococcal beta-hemolysin, for detection of hemolysin(s) produced by Vibrio cholerae biotype El Tor.

A tube test using brain heart infusion broth and staphylococcal B-lysin (HIBL) was devised to improve the detection of Vibrio cholerae El Tor hemolysin. Fifty six (100%) strains of V. cholerae serotypes Ogawa (28) and Inaba (28) were positive by the hemolysin test whereas 4 Inaba and 2 Ogawa were positive by a standard tube test using heart infusion broth (HIB) and 20 Ogawa and 18 Inaba were positive by another tube test using HIB containing glycerol (HIBG). Seven classical V. cholerae strains tested were negative by the 3 methods. The HIBL tube test was faster and more sensitive than the other 2 methods and showed that hemolysin was present that would otherwise have gone undetected by the other 2 methods using HIB or HIBG.