Extended scheme for serotyping Campylobacter jejuni: results obtained in Israel from 1980 to 1981.

The serotyping scheme for Campylobacter jejuni previously developed in the National Center for Campylobacter, Jerusalem, was extended by the use of 20 new sera and modified by the absorption of the sera, when necessary, with homologous boiled cultures or heterologous live cultures. The extended scheme is based on slide agglutination of live suspensions and is performed in two stages: pretesting with four pooled sera and final testing with monovalent sera. So far, 34 serotypes have been recognized. Among 442 isolates of C. jejuni, 86.4% could be typed with this scheme. Of the 382 cultures typed, 90% reacted with one single serum, and the remainder showed a complex antigenic structure. The frequent serotypes identified were: 11 (12.9%), 12 (8.2%), 18 (6.3%), and 3 (6.1%). When epidemiological data were available, the results of the serotyping corresponded with the epidemiological evidence.