Preliminary Incidence and Trends of Infections With Pathogens Transmitted Commonly Through Food

Foodborne Diseases Active Surveillance Network, 10 U.S. Sites, 2015-2018

Danielle M. Tack, DVM; Ellyn P. Marder, MPH; Patricia M. Griffin, MD; Paul R. Cieslak, MD; John Dunn, DVM; Sharon Hurd, MPH; Elaine Scallan, PhD; Sarah Lathrop, PhD; Alison Muse, MPH; Patricia Ryan, MD; Kirk Smith, DVM; Melissa Tobin-D'Angelo, MD; Duc J. Vugia, MD; Kristin G. Holt, DVM; Beverly J. Wolpert, PhD; Robert Tauxe, MD; Aimee L. Geissler, PhD


Morbidity and Mortality Weekly Report. 2019;68(16):369-373. 

In This Article

Abstract and Introduction


Foodborne diseases represent a major health problem in the United States. The Foodborne Diseases Active Surveillance Network (FoodNet) of CDC's Emerging Infections Program monitors cases of laboratory-diagnosed infection caused by eight pathogens transmitted commonly through food in 10 U.S. sites.* This report summarizes preliminary 2018 data and changes since 2015. During 2018, FoodNet identified 25,606 infections, 5,893 hospitalizations, and 120 deaths. The incidence of most infections is increasing, including those caused by Campylobacter and Salmonella, which might be partially attributable to the increased use of culture-independent diagnostic tests (CIDTs). The incidence of Cyclospora infections increased markedly compared with 2015–2017, in part related to large outbreaks associated with produce.[1] More targeted prevention measures are needed on produce farms, food animal farms, and in meat and poultry processing establishments to make food safer and decrease human illness.

FoodNet conducts active, population-based surveillance for laboratory-diagnosed infections caused by Campylobacter, Cyclospora, Listeria, Salmonella, Shiga toxin–producing Escherichia coli (STEC), Shigella, Vibrio, and Yersinia in 10 sites covering 15% of the U.S. population (approximately 49 million persons in 2017). FoodNet is a collaboration among CDC, 10 state health departments, the U.S. Department of Agriculture's Food Safety and Inspection Service (USDA-FSIS), and the Food and Drug Administration (FDA). Bacterial infections are defined as isolation of the bacterium from a clinical specimen or detection of pathogen antigen, nucleic acid sequences, or, for STEC, Shiga toxin or Shiga toxin genes. Listeria cases are defined as isolation of L. monocytogenes or detection of its nucleic acid sequences from a normally sterile site or from placental or fetal tissue in cases of miscarriage or stillbirth. Cyclospora infections are defined as detection of the parasite from a clinical specimen by direct fluorescent antibody, polymerase chain reaction, or light microscopy. Hospitalizations occurring within 7 days of specimen collection are attributed to the infection, as is the patient's vital status at hospital discharge, or 7 days after specimen collection if the patient was not hospitalized.

Incidence per 100,000 population was calculated by dividing the number of infections in 2018 by U.S. Census estimates of the surveillance area population for 2017. A negative binomial model with 95% confidence intervals (CIs) was calculated using SAS (version 9.4; SAS Institute) to estimate changes in incidence.

Surveillance for physician-diagnosed postdiarrheal hemolytic uremic syndrome, a complication of STEC infection characterized by renal failure, thrombocytopenia, and microangiopathic anemia, is conducted through a network of nephrologists and infection preventionists and by hospital discharge data review. This report includes pediatric hemolytic uremic syndrome cases (those occurring in persons aged <18 years) identified during 2017, the most recent year for which data are available.

*Connecticut, Georgia, Maryland, Minnesota, New Mexico, Oregon, Tennessee, and selected counties in California, Colorado, and New York (
STEC cases are defined as identification of Shiga toxin or its genes by any laboratory; it is not possible to distinguish among serogroups using CIDTs.