Abstract
Infections from Shigella spp. and Enteroinvasive Escherichia coli (EIEC) are considered leading causes of symptomatic diarrheal disease, globally. However, there is a paucity of case-control studies from Caribbean nations to guide regional public health priorities and interventions. A case-control study was conducted within a larger cross-sectional healthcare study in Haïti. Participant households were identified using a geospatially randomized method; families with children under 5 years were consented and enrolled. Rectal swabs from child participants were tested for Shigella spp./EIEC by qPCR using the ipaH target. Two case-definitions were used: 'diarrheal symptom' (DS) cases were defined as those reporting diarrheal symptoms ≤7 days ago; 'acute diarrhea' (AD) cases were defined as those reporting diarrheal symptoms ≤7 days ago with ≥3 loose stools in the past 24 hours and onset <7 days ago. Of 868 households screened, 568 were enrolled with 794 participating children; samples from 732 children were analyzed. Rates of Shigella spp./EIEC. detection among DS cases and controls were 11.4% (22/193) and 6.1% (33/539), respectively. Rates of detection among AD cases and controls were 18.6% (8/43) and 6.8% (47/689), respectively. The adjusted odds of having DS increased by 84% (aOR=1.84; 95%CI 1.02 to 3.27) and having AD increased by 183% (aOR=2.83; 95%CI 1.14 to 6.36) when Shigella spp./EIEC was detected. The attributable fractions for DS and AD were 5.62% (95%CI 0.44% to 10.9%) and 12.6% (95%CI 0% to 25.3%), respectively. Rates of bloody diarrhea (dysentery) were minimal (<1%, 6/732). Within this case-control study in Haïti, Shigella spp./EIEC detection was common and attributed to symptomatic disease. These results align with prior global health studies. Shigella spp./EIEC represent an important public health target for intervention once the security situation in Haïti stabilizes.