A monkey model for enterohemorrhagic Escherichia coli infection

Adult Macaca radiata (n=22) were infected intragastrically with 10(12) Esch erichia coli O157: H7 strain 84-01, which produces Shiga toxins 1 and 2. Cl inical symptoms and bacterial excretion were documented in each monkey for a specified time period before they were killed. At necropsy, samples were obtained for culture and histologic and ultrastructural examination. Sevent een monkeys had diarrhea: E. coli O157 was isolated from postinfection stoo l samples from all monkeys and from autopsy cultures for 14 of 22 monkeys. Histologic examination showed attaching-effacing lesions, which appeared at 12 h and persisted for 7 days, in 12 monkeys. Widening of the intercellula r spaces, degeneration and vacuolization of the epithelial cells, epithelia l tufting, extrusion of epithelial cells, and neutrophilic infiltration wer e characteristic features seen in 20 of the 22 infected monkeys but not in 4 control monkeys. This monkey model closely parallels the early stages of the disease produced by E. coli O157: H7 and would be useful in the further study of pathogenic mechanisms and prevention methods in enterohemorrhagic E. coli infections.