CDC: Foodborne illnesses decreased during the COVID-19 pandemic
The COVID-19 pandemic may have been good for one thing.
A new report from the Centers for Disease Control and Prevention shows that foodborne illness infections in 2020 decreased by nearly one-quarter compared with the previous three-year average.
The report, was published Sept. 24 in the CDC’s Morbidity and Mortality Weekly Report.
Before 2020, the incidence of infections transmitted commonly by food had not declined for many years, according to the report. However, during 2020, FoodNet identified 26% fewer infections compared with the average annual number during 2017-19, including decreased infections associated with international travel.
FoodNet is shorthand for the Foodborne Diseases Active Surveillance Network, a CDC program that monitors the incidence of laboratory-diagnosed infections caused by eight pathogens transmitted commonly through food reported by 10 U.S. sites. FoodNet is a collaboration among CDC, 10 state health departments, the U.S. Department of Agriculture’s Food Safety and Inspection Service, and the Food and Drug Administration
FoodNet conducts active, population-based surveillance of laboratory-diagnosed infections caused by campylobacter, cyclospora, listeria, salmonella, Shiga toxin-producing Escherichia coli (STEC), shigella, vibrio, and yersinia reported from 10 sites covering approximately 15% of the U.S. population, according to the report.
During 2020, the report said FoodNet identified 18,462 cases of infection, 4,788 hospitalizations, and 118 deaths.
The overall incidence was highest for campylobacter (14.4 per 100,000 population), followed by salmonella (13.3), STEC (3.6), shigella (3.1), yersinia (0.9), vibrio (0.7), cyclospora (0.6) and listeria (0.2). The incidence in 2020 was significantly lower for all pathogens except yersinia and cyclospora. The percentage of infections resulting in hospitalization increased 2% compared with 2017-19, the CDC report said.
Looking for a reason
According to CDC, the implications of the 2020 decline in foodborne illness infections are not easily explained.
“The pandemic and resulting public health response present challenges to explaining changes in observed foodborne illness incidences,” the report said. “Continued surveillance might help elucidate the impact of the COVID-19 pandemic on foodborne illness and identify strategies to decrease illnesses.”
The extent to which these reductions in foodborne illness infections reflect actual decreases in illness or decreases in case detection is unknown, according to the report. On March 13, 2020, the U.S. declared a national emergency in response to the COVID-19 pandemic, the report noted.
After the declaration, state and local officials implemented stay-at-home orders, restaurant closures, school and childcare center closures, and other public health interventions to slow the spread of SARS-CoV-2, the virus that causes COVID-19. Federal travel restrictions also were in place.
“These widespread interventions as well as other changes to daily life and hygiene behaviors, including increased handwashing, have likely changed exposures to foodborne pathogens,” the report said.
Other factors, such as changes in health care delivery, health care-seeking behaviors, and laboratory testing practices, might have decreased the detection of enteric infections.
Historic decline
The 26% decrease in incidence of infections caused by pathogens transmitted commonly through food during 2020 was the largest single-year variation in incidence during 25 years of FoodNet surveillance, the CDC said.
Widespread public health interventions implemented to prevent SARS-CoV-2 transmission might have contributed to this decrease. For example, infections associated with international travel decreased markedly after pandemic-related travel restrictions were imposed, the CDC said.
Other interventions, such as restaurant closures, might have contributed to declines in incidence.
However, the report said a higher than usual proportion of infections might have been undetected because factors such as changes in health care-seeking behaviors and broader use of telehealth might have limited the number of stool specimens tested. Marked decreases in emergency department visits for abdominal pain and other digestive or abdominal signs and symptoms occurred early in the pandemic.
The report said concerted efforts are still needed to reduce the incidence of foodborne illness infections from farm to processing plant to restaurants and homes. Consumers can reduce their risk of foodborne illness by following safe food-handling and preparation recommendations, the CDC said.
