Quantifying Kids’ Increased Risk for Foodborne Illness

It’s long been known that young children account for a disproportionately high percentage of foodborne illness cases. But public health experts have questioned whether that’s because kids are more susceptible to pathogens or because parents are more likely to take a child for a doctor visit, thus generating an official report of illness.

The answer, according to new research published in the Pediatric Infectious Disease Journal, is yes to both. Although cases involving kids under age five are more likely to be diagnosed than cases involving adults, children still fall ill due to pathogens such as Salmonella, E. coli, and Campylobacter at a higher rate.

Researchers at the University of Colorado in Denver studied five major bacterial enteric illnesses in children, using a statistical model that scaled counts of laboratory-confirmed illnesses from the Foodborne Diseases Active Surveillance Network. These five pathogens, including Salmonella, Campylobacter, Shigella, Y. enterocolitica, and E. coli, cause nearly 300,000 illnesses among children under age five each year.

“As we expected, we found that children are more likely than adults to be captured in surveillance systems when they do become ill,” said Elaine Scallan, PhD, assistant professor of epidemiology and former lead of the CDC’s FoodNet surveillance system. “For example, with Salmonella, every diagnosed case represents 29 additional undiagnosed cases in the community. But among young children, for every case, there are just 12 that go undiagnosed.”

Even given that higher diagnosis rate, children still appear to be more vulnerable to such illnesses than adults. “Again, looking at Salmonella, the rate in the community is about 400 or so illnesses per 100,000 individuals; that’s including those who didn’t seek care, those who sought care but didn’t get diagnosed, and those who had a lab test but were never properly identified—as well as those who were accurately diagnosed,” said Dr. Scallan. “Among children, the rate of illnesses is just over 600 per 100,000. Knowing that this is a more vulnerable age group that can have more serious outcomes, we really need to emphasize the need for prevention efforts targeted at this age group.”