Organisms Causing Food Poisoning in Children
Viral Pathogens Dominate Overall Burden
Norovirus is the leading cause of foodborne illness in children, accounting for 58% of all foodborne gastroenteritis cases and causing nearly 1 million ambulatory care visits and 14,000 hospitalizations annually in children under 5 years. 1, 2
- Rotavirus historically caused 3 million annual episodes before vaccine introduction, with over 500,000 outpatient visits and 27,000 hospitalizations, but has declined significantly since vaccination programs began. 1, 2
- Most viral gastroenteritis cases are self-limited and do not require laboratory testing in previously healthy, immunocompetent children. 2
Bacterial Pathogens Cause More Severe Disease
Among the five most common bacterial pathogens in children under 5 years, the distribution is as follows:
Salmonella enterica subspecies (42% of bacterial cases)
- Salmonella is the leading cause of hospitalization (35%) and death (28%) among all foodborne bacterial pathogens in children. 1, 2
- Most commonly linked to poultry products and produce contamination. 1, 3
Campylobacter (28% of bacterial cases)
- Second most common bacterial pathogen after Salmonella. 1, 4
- Frequently attributed to undercooked chicken products. 4, 3
- Testing warranted when children present with bloody or mucoid stools, fever, and abdominal tenderness. 4
Shigella (21% of bacterial cases)
- Causes dysentery with frequent scant stools containing blood and mucus. 1
- More common in developing countries but remains significant in U.S. pediatric populations. 1
Yersinia enterocolitica (5% of bacterial cases)
- Consider in school-aged children with right lower quadrant abdominal pain mimicking appendicitis, as this may represent mesenteric adenitis. 4
- Higher risk in young African American and Asian children, diabetics, and those with chronic liver disease or iron-overload states. 4
E. coli O157 (3% of bacterial cases)
- Causes severe diarrheal disease and hemolytic uremic syndrome (HUS), with 60% of patients developing these life-threatening complications. 1, 5
- Predominantly affects young children with potentially fatal outcomes. 5
Additional High-Risk Pathogens from Specific Sources
Raw Milk-Associated Pathogens
Children should never consume raw milk due to severe, life-threatening bacterial infections. 5
- Listeria monocytogenes causes invasive disease resulting in pneumonia, sepsis, or meningitis in two-thirds of infected neonates. 5
- Brucella abortus causes brucellosis with prolonged fever and multi-organ involvement. 5
- Mycobacterium tuberculosis transmission through raw milk caused hundreds of outbreaks before pasteurization became standard. 5
- From 1998-2009, raw milk consumption resulted in 93 illness outbreaks, with 79% involving at least one person younger than 20 years. 5
Parasitic Pathogens
- Giardia and Cryptosporidium are detected in 0.77-3% and 3.07% of cases, respectively. 2
- These parasites cause prolonged diarrheal illness requiring specific diagnostic testing with fluorescence and EIA methods. 1, 2
Critical Clinical Decision Points
When to Test
Laboratory investigation is warranted when: 1
- Bloody or mucoid stools suggest bacterial pathogens
- Fever with abdominal tenderness is present
- Immunocompromised status exists
- Outbreak situation is suspected
- Symptoms persist beyond 7 days
Common Pitfall to Avoid
Do not routinely test for parasites or perform stool cultures in previously healthy children with acute watery diarrhea lasting less than 7 days, as most cases are viral and self-limited. 1, 2 Reserve testing for the specific clinical scenarios listed above to avoid unnecessary healthcare costs and antibiotic overuse.