DuPont, H. L (Univ. of Maryland School of Medicine, Baltimore, Md. 21201), E. J. Gangarosa, L. B. Reller, W. E Woodward, R. W. Armstrong, J. Hammond, K. Glaser and G. K. Morris. Shigellosis in custodial institutions. Amer, J. Epid., 1970, 92: 172–174.—Prior to the field testing of oral live shigella vaccine, epidemiologic and clinical investigations of shigellosis occurring at two large custodial institutions were conducted. Thirty-two % of the children admitted in 1967 to Willowbrook State School, New York and 10% of those admitted to Rosewood State Hospital, Maryland, developed bacillary dysentery within 12 months following admission. In a group of children housed at Willowbrook in areas where shigellosis had occurred, attack rates were higher in the first two years following admission and fell during subsequent two-year periods, indicating the development of some immunity after prolonged exposure. Prevalence cultural surveys showed that between 6–7% of asymptomatic children housed in those areas at each institution where shigellosis was known to occur were positive for a shigella strain. The infecting strain causing shigellosis was most frequently S. flexneri 2 or S. sonnei, and usually resistant to widely employed antimicrobials. While most infected children appeared to respond to antibiotic therapy (75% at Willowbrook, 85% at Rosewood), some excreted shigellae intermittently for more than a year (37 of 542 cases at Willowbrook).