NOTES: Proposals for Improving the Classification of Members of the Genus Shigella

With respect to Shigella flexneri, serovar 6 should be transferred to S. boydii; serovar 5 should be divided into two subserovars, 5a and 5b, with antigenic formulas V:(4) and V:7, respectively; and serovar 3 should contain only two subserovars, 3a-III:(3,4),6 and 3b-III:(3,4),6,7,8. Concerning the six provisional Shigella serovars, serovar 2000-53 should be removed from the genus because it belongs to the genus Escherichia, the position of serovar 1624-54 is still under consideration, serovars 3873-50 and 3341-55 should be placed in S. dysenteriae as serovars 11 and 12, respectively, and serovars 2710-54 and 3615-53 should be considered as members of S. boydii serovars 16 and 17, respectively.