McCrickard LS, et al. - This study offers information regarding severe shigellosis among US adults. As per data, the highest incidence of severe shigellosis was reported among adults, men 18–49 years old, blacks in particular. Among adults with shigellosis, association of severe shigellosis with being male in age group 18–49 years, with infections caused by S. flexneri, and with black race, was apparent.