A revised update of the International antigenic scheme for Plesiomonas shig
elloides is presented. Twenty-six new O (O77-O102) and 10 new H (H42-H50 an
d H1a1d) antigens have been described since 1994. The sources of antigens a
re mostly human clinical strains, isolates from warmblooded animals and a f
ew environmental cultures.