Fig. 5.
Determination of the ID50 for stool and in vitro grown V. cholerae. Groups of five mice were infected with either stool V. cholerae O1 El Tor serotype Ogawa (filled circles) or strain AC-V999 grown overnight in vitro (empty circles). The doses used are shown on the x-axis, and the percentage of mice infected after 24 h is shown on the y-axis. The ID50 value for each was determined graphically and is indicated by the broken lines.