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

Foodborne Diseases Active Surveillance Network, 10 U.S. Sites, 2006-2014

Stacy M. Crim, MPH; Patricia M. Griffin, MD; Robert Tauxe, MD; Ellyn P. Marder, MPH; Debra Gilliss, MD; Alicia B. Cronquist, MPH; Matthew Cartter, MD; Melissa Tobin-D'Angelo, MD; David Blythe, MD; Kirk Smith, DVM; Sarah Lathrop, PhD; Shelley Zansky, PhD; Paul R. Cieslak, MD; John Dunn, DVM; Kristin G. Holt, DVM; Beverly Wolpert, PhD; Olga L. Henao, PhD


Morbidity and Mortality Weekly Report. 2015;64(18):495-499. 

In This Article

Cases of Infection, Incidence, and Trends

In 2014, FoodNet identified 19,542 cases of infection, 4,445 hospitalizations, and 71 deaths (Table). The number and incidence per 100,000 population were as follows: Salmonella (7,452 [15.45]), Campylobacter (6,486 [13.45]), Shigella (2,801 [5.81]), Cryptosporidium (1,175 [2.44]), STEC non-O157 (690 [1.43]), STEC O157 (445 [0.92]), Vibrio (216 [0.45]), Yersinia (133 [0.28]), Listeria (118 [0.24]), and Cyclospora (26 [0.05]). The percentage of infections associated with outbreaks was as follows: STEC O157 (16%), Listeria (11%), STEC non-O157 (7%), Shigella (7%), Salmonella (6%), Vibrio (6%), Cryptosporidium (5%), Yersinia (0.8%), and Campylobacter (0.6%).

Among 6,565 (88%) serotyped Salmonella isolates in 2014, the number and incidence per 100,000 population of the top six serotypes were as follows: Enteritidis (1,401 [2.90]), Typhimurium (806 [1.67]), Newport (724 [1.50]), Javiana (639 [1.32]), I 4,[5],12:i:- (381 [0.79]), and Infantis (235 [0.49]). Among 208 (96%) speciated Vibrio isolates, 131 (63%) were V. parahaemolyticus, 27 (13%) were V. alginolyticus, and 19 (9%) were V. vulnificus. Among 546 (79%) serogrouped STEC non-O157 isolates, the top serogroups were O26 (31%), O103 (24%), and O111 (19%).

Compared with 2006–2008, the 2014 incidence was significantly lower for STEC O157 (32% decrease; CI = 18%–43%) and Yersinia (22% decrease; CI = 1%–39%) infections, higher for Vibrio (52% increase; CI = 22%–89%) and Campylobacter (13% increase; CI = 5%–21%) infections, and not significantly changed for other pathogens (Figure 1). Among the six most commonly identified Salmonella serotypes, the incidence was significantly lower in 2014 for Typhimurium (27% decrease; CI = 18%–35%) compared with 2006–2008, but significantly higher for Infantis (162% increase; CI = 100%–244%) and Javiana (131% increase; CI = 83%–191%). Incidence for the three serotypes with significant changes in 2014 was calculated for the period 2006–2014 (Figure 2). Compared with 2011–2013, the 2014 incidence was significantly lower for STEC O157 and Salmonella serotype Typhimurium infections and higher for STEC non-O157 and Salmonella serotype Infantis infections. The overall incidence of infection with the six key foodborne pathogens was not significantly different from either of the comparison periods.

Figure 1.

Relative rates of culture-confirmed infections with Campylobacter, STEC* O157, Listeria, Salmonella, and Vibrio compared with 2006–2008 rates, by year — Foodborne Diseases Active Surveillance Network, United States, 2006–2014
* Shiga toxin–producing Escherichia coli.
The position of each line indicates the relative change in the incidence of that pathogen compared with 2006–2008. The actual incidences of these infections cannot be determined from this figure.

Figure 2.

Incidence per 100,000 population of culture-confirmed infection with Salmonella serotypes Typhimurium, Javiana, and Infantis, by year — Foodborne Diseases Active Surveillance Network, United States, 2006–2014

In 2013, a total of 87 cases of postdiarrheal hemolytic uremic syndrome were reported among children aged <18 years (0.79 cases per 100,000). Of these, 46 (53%) occurred in children aged <5 years (1.55 cases per 100,000). The incidence of hemolytic uremic syndrome was not significantly different than during 2006–2008 for either age group. No deaths were reported.

In addition to culture-confirmed infections (some with positive culture-independent diagnostic test results), there were 1,597 reports of positive culture-independent diagnostic tests that were not confirmed by culture, either because a culture did not yield the pathogen or because the specimen was not cultured. These reports were not included in the overall count of cases. Among 1,070 Campylobacter reports in this category, 553 (52%) had no culture, and 517 (48%) were culture-negative. Among 146 STEC reports, 62 (42%) had no culture, and 84 (58%) were culture-negative. The Shiga toxin–positive result was confirmed for 65 (48%) of 135 broths sent to a public health laboratory. The other reports of positive culture-independent diagnostic tests where culture was negative or not performed were of Salmonella (193), Shigella (186), and Vibrio (two).