In 2012, the incidence of infections caused by Campylobacter and Vibrio increased from the 2006–2008 period, whereas the incidence of infections caused by Cryptosporidium, Listeria, Salmonella, Shigella, STEC O157, and Yersinia was unchanged. These findings highlight the need to continue to identify and address food safety gaps that can be targeted for action by the food industry and regulatory authorities.

After substantial declines in the early years of FoodNet surveillance, the incidence of Campylobacter infection has increased to its highest level since 2000. Campylobacter infections are more common in the western U.S. states and among children aged <5 years (3). Although most infections are self-limited, sequelae include reactive arthritis and Guillain-Barré syndrome.§§ Associated exposures include consumption of poultry, raw milk, produce, and untreated water, and animal contact (4,5).

Declines in U.S. campylobacteriosis during 1996–2001 might have been related to measures meat and poultry processors implemented to comply with the Pathogen Reduction and Hazard Analysis and Critical Control Points (HACCP) systems regulations issued by USDA-FSIS in the late 1990s.¶¶ In 2011, USDA-FSIS issued new Campylobacter performance standards for U.S. chicken and turkey processors.*** Continued FoodNet surveillance can help to assess the public health impact of these standards and other changes. Detailed patient exposure information coupled with information on strain subtypes could help in assessing the relative contribution of various sources of infection and the effectiveness of control measures.

Although a significant increase was observed in reported Vibrio infections, the number of such infections remains low (6). Vibrios live naturally in marine and estuarine waters, and many infections are acquired by eating raw oysters (7). These infections are most common during warmer months, when waters contain more Vibrio organisms. Infections can be prevented by postharvest treatment of oysters with heat, freezing, or high pressure (8), or by thorough cooking. Persons who are immunocompromised or have impaired liver function should be informed that consuming raw seafood carries a risk for severe Vibrio infection. Vibrios also cause wound and soft-tissue infections among persons who have contact with water; for example, Vibrio alginolyticus typically causes ear infection (9).

The decrease in incidence of HUS in 2011 compared with 2006–2008 mirrors the decrease in the incidence of STEC O157 infection observed in 2011. The incidence of STEC O157 infection, which had declined since 2006, was no longer decreasing in 2012, and now exceeds the previously met Healthy People 2010 target of one case per 100,000 persons. The continued increase in STEC non-O157 infections likely reflects increasing use by clinical laboratories of tests that detect these infections.

FoodNet surveillance relies on isolation of bacterial pathogens by culture of clinical specimens; therefore, the increasing use of culture-independent tests for Campylobacter and STEC might affect the reported incidence of infection (10). Data on persons with only culture-independent evidence of infection suggests that in 2012, the number of laboratory-identified Campylobacter cases could have been 9% greater and the number of STEC (O157 and non-O157) cases 7%–19% greater than that reported (CDC, unpublished data, 2013). The lack of recent decline in STEC O157 incidence is of concern; continued monitoring of trends in the incidence of HUS and use of culture-independent testing might aid in interpreting future data on STEC O157 incidence.

The findings in this report are subject to at least four limitations. First, health-care–seeking behaviors and other characteristics of the population in the surveillance area might affect the generalizability of the findings. Second, many infections transmitted commonly through food (e.g., norovirus infection) are not monitored by FoodNet because these pathogens are not identified routinely in clinical laboratories. Third, the proportion of illnesses transmitted by nonfood routes differs by pathogen, and the route cannot be determined for individual, nonoutbreak-associated illnesses and, therefore, the data provided in this report do not exclusively relate to infections from foodborne sources. Finally, in some cases counted as fatal, the infection with the enteric pathogen might not have been the primary cause of death.

Most foodborne illnesses can be prevented. Progress has been made in decreasing contamination of some foods and reducing illness caused by some pathogens, as evidenced by decreases in earlier years. In 2010, FDA passed the Egg Safety Rule,††† designed to decrease contamination of shell eggs with Salmonella serotype Enteritidis. In 2011, USDA-FSIS tightened its performance standard for Salmonella contamination to a 7.5% positive rate for whole broiler chickens.§§§ Finally, the Food Safety Modernization Act of 2011 gives FDA additional authority to improve food safety and requires CDC to strengthen surveillance and outbreak response.¶¶¶ Collection of comprehensive surveillance information further supports reductions in foodborne infections by helping to determine where to target prevention efforts, supporting efforts to attribute infections to sources, guiding implementation of measures known to reduce food contamination, and informing development of new measures. Because consumers can bring an added measure of safety during food storage, handling, and preparation, they are advised to seek out food safety information, which is available online.****