Background: Many enteric pathogens disproportionately affect young children. However, higher incidences of laboratory-confirmed illness may be explained, at least in part, by higher rates of medical care-seeking and stool sample submission in this age group. We estimated the overall number of bacterial enteric illnesses among children <5 years old in the United States caused by Campylobacter, Escherichia coli O157, nontyphoidal Salmonella, Shigella and Yersinia enterocolitica.
Materials and methods: We used a statistical model that scaled counts of laboratory-confirmed illnesses from the Foodborne Diseases Active Surveillance Network up to an estimated number of illnesses in the United States, adjusting for the surveillance steps needed for an illness to be laboratory diagnosed (medical care sought, stool sample submitted, bacterial culture performed, laboratory tested for pathogen, laboratory test sensitivity).
Results: We estimated that 5 bacterial enteric pathogens caused 291,162 illnesses each year among children <5 years old, resulting in 102,746 physician visits, 7830 hospitalizations and 64 deaths. Nontyphoidal Salmonella caused most illnesses (42%), followed by Campylobacter (28%), Shigella (21%), Y. enterocolitica (5%) and E. coli O157 (3%). The estimated annual number of physician visits ranged from 3763 for E. coli O157 to 44,369 for nontyphoidal Salmonella. Nontyphoidal Salmonella was estimated to cause most hospitalizations (4670) and deaths (38).
Conclusions: Bacterial enteric infections cause many illnesses in US children. Compared with the general population, enteric illnesses among children <5 years old are more likely to be diagnosed. However, overall rates of illness remain higher in children after adjusting for underdiagnosis in both groups.