Five percent of 330 sera from natives reacted positively in high dilutions against B. Dysenteriae Shiga. Two percent of 500 sera reacted positively in a dilution of 1 in 250 against B. Dysenteriae Flexner. The ""V"" and ""Y"" types predominated. No positive results were obtained against B. dysenteriae Sonne. It is assumed that some of these reactors are chronic carriers, and it is hoped to investigate this aspect.