Foodborne Illness Outbreaks at Retail Establishments - National Environmental Assessment Reporting System, 16 State and Local Health Departments, 2014-2016.

PROBLEM/CONDITION: State and local public health departments report hundreds of foodborne illness outbreaks each year to CDC and are primarily responsible for investigations of these outbreaks. Typically, investigations involve epidemiology, laboratory, and environmental health components. Health departments voluntarily report epidemiologic and laboratory data from their foodborne illness outbreak investigations to CDC through the Foodborne Disease Outbreak Surveillance System (FDOSS); however, minimal environmental health data from outbreak investigations are reported to FDOSS. PERIOD COVERED: 2014-2016. DESCRIPTION OF SYSTEM: In 2014, CDC launched the National Environmental Assessment Reporting System (NEARS) to complement FDOSS surveillance and to use these data to enhance prevention efforts. State and local health departments voluntarily report data from their foodborne illness outbreak investigations of retail food establishments. These data include characteristics of foodborne illness outbreaks (e.g., agent), characteristics of establishments with outbreaks (e.g., number of meals served daily), food safety policies and practices of these establishments (e.g., glove use policies), and characteristics of outbreak investigations (e.g., timeliness of investigation activities). NEARS is the only available data source that includes characteristics of retail establishments with foodborne illness outbreaks. RESULTS: During 2014-2016, a total of 16 state and local public health departments reported data to NEARS on 404 foodborne illness outbreaks at retail establishments. The majority of outbreaks with a suspected or confirmed agent were caused by norovirus (61.1%). The majority of outbreaks with identified contributing factors had at least one factor associated with food contamination by a worker who was ill or infectious (58.6%). Almost half (47.4%) of establishments with outbreaks had a written policy excluding ill workers from handling food or working. Approximately one third (27.7%) had a written disposable glove use policy. Paid sick leave was available for at least one worker in 38.3% of establishments. For most establishments with outbreaks (68.7%), environmental health investigators initiated their component of the investigation soon after learning about the outbreak (i.e., the same day) and completed their component in one or two visits to the establishment (75.0%). However, in certain instances, contacting the establishment and completing the environmental health component of the investigation occurred much later (>8 days). INTERPRETATION: Most outbreaks reported to NEARS were caused by norovirus, and contamination of food by workers who were ill or infectious contributed to more than half of outbreaks with contributing factors; these findings are consistent with findings from other national outbreak data sets and highlight the role of workers in foodborne illness outbreaks. The relative lack of written policies for ill workers and glove use and paid sick leave for workers in establishments with outbreaks indicates gaps in food safety practices that might have a role in outbreak prevention. The environmental health component of the investigation for most outbreaks was initiated quickly, yet the longer initiation timeframe for certain outbreaks suggests the need for improvement. PUBLIC HEALTH ACTION: Retail establishments can reduce viral foodborne illness outbreaks by protecting food from contamination through proper hand hygiene and excluding workers who are ill or infectious from working. NEARS data can help prioritize training and interventions for state and local food safety programs and the retail food establishment industry by identifying gaps in food safety policies and practices and types of establishments vulnerable to outbreaks. Improvement of certain outbreak investigation practices (e.g., delayed initiation of environmental health investigations) can accelerate identification of the agent and implementation of interventions. Future analysis comparing establishments with and without outbreaks will contribute knowledge about how establishments' characteristics and food safety policies and practices relate to foodborne illness outbreaks and provide information to develop effective prevention approaches.

Ground beef handling and cooking practices in restaurants in eight States.

Eating in table-service restaurants has been implicated as a risk factor for Escherichia coli O157:H7 infection. To explore this association and learn about the prevalence of risky ground beef preparation practices in restaurants, the Environmental Health Specialists Network (EHS-Net) assessed ground beef handling policies and practices in restaurants in California, Colorado, Connecticut, Georgia, Minnesota, New York, Oregon, and Tennessee. Eligible restaurants prepared and served hamburgers. EHS-Net specialists interviewed a restaurant employee with authority over the kitchen (defined as the manager) using a standard questionnaire about food safety policies, hamburger preparation policies, and use of irradiated ground beef. Interviews were followed by observations of ground beef preparation. Data from 385 restaurants were analyzed: 67% of the restaurants were independently owned and 33% were chain restaurants; 75% of the restaurants were sit down, 19% were quick service or fast food, and 6% were cafeteria or buffet restaurants. Eighty-one percent of restaurants reported determining doneness of hamburgers by one or more subjective measures, and 49% reported that they never measure the final cook temperatures of hamburgers. At least two risky ground beef handling practices were observed in 53% of restaurants. Only 1% of restaurants reported purchasing irradiated ground beef, and 29% were unfamiliar with irradiated ground beef. Differences in risky ground beef handling policies and practices were noted for type of restaurant ownership (independently owned versus chain) and type of food service style (sit down versus quick service or fast food). This study revealed the pervasiveness of risky ground beef handling policies and practices in restaurants and the need for educational campaigns targeting food workers and managers. These results highlight the importance of continued efforts to reduce the prevalence of E. coli O157:H7 in ground beef.

Tomato handling practices in restaurants.

In recent years, multiple outbreaks of Salmonella infection have been associated with fresh tomatoes. Investigations have indicated that tomato contamination likely occurred early in the farm-to-consumer chain, although tomato consumption occurred mostly in restaurants. Researchers have hypothesized that tomato handling practices in restaurants may contribute to these outbreaks. However, few empirical data exist on how restaurant workers handle tomatoes. This study was conducted to examine tomato handling practices in restaurants. Members of the Environmental Health Specialists Network (EHS-Net) observed tomato handling practices in 449 restaurants. The data indicated that handling tomatoes appropriately posed a challenge to many restaurants. Produce-only cutting boards were not used on 49% of tomato cutting observations, and gloves were not worn in 36% of tomato cutting observations. Although tomatoes were washed under running water as recommended in most (82%) of the washing observations, tomatoes were soaked in standing water, a practice not recommended by the U.S. Food and Drug Administration (FDA), in 18% of observations, and the temperature differential between the wash water and tomatoes did not meet FDA guidelines in 21% of observations. About half of all batches of cut tomatoes in holding areas were above 41 degrees F (5 degrees C), the temperature recommended by the FDA. The maximum holding time for most (73%) of the cut tomatoes held above 41 degrees F exceeded the FDA recommended holding time of 4 h for unrefrigerated tomatoes (i.e., tomatoes held above 41 degrees F). The information provided by this study can be used to inform efforts to develop interventions and thus prevent tomato-associated illness outbreaks.

Certified kitchen managers: do they improve restaurant inspection outcomes?

Restaurants are associated with a significant number of foodborne illness outbreaks in the United States. Certification of kitchen managers through an accredited training and testing program may help improve food safety practices and thus prevent foodborne illness. In this study, relationships between the results of routine restaurant inspections and the presence of a certified kitchen manager (CKM) were examined. We analyzed data for 4461 restaurants in Iowa that were inspected during 2005 and 2006 (8338 total inspections). Using logistic regression analysis, we modeled the outcome variable (0 = no critical violations [CVs]; 1 = one or more CVs) as a function of presence or absence of a CKM and other explanatory variables. We estimated separate models for seven inspection categories. Restaurants with a CKM present during inspection were less likely to have a CV for personnel (P < 0.01), food source or handling (P < 0.01), facility or equipment requirements (P < 0.05), ware-washing (P < 0.10), and other operations (P < 0.10). However, restaurants with a CKM present during inspection were equally likely to have a CV for temperature or time control and plumbing, water, or sewage as were restaurants without a CKM present. Analyses by type of violation within the temperature and time control category revealed that restaurants with a CKM present during inspection were less likely to have a CV for hot holding (P < 0.05), but the presence of a CKM did not affect other types of temperature and time control violations. Our analyses suggest that the presence of a CKM is protective for most types of CVs, and we identify areas for improving training of CKMs.

Factors related to food worker hand hygiene practices.

To identify factors related to food worker hand hygiene practices, we collected (i) observational data on food worker (n = 321) hand hygiene practices (hand washing and glove use) and (ii) observational and interview data on factors related to hygiene behavior, such as worker activity, restaurant characteristics, worker food safety training, and the physical and social environment. Results indicated that hand washing and glove use were more likely to occur in conjunction with food preparation than with other activities (e.g., handling dirty equipment) and when workers were not busy. Hand washing was more likely to occur in restaurants whose food workers received food safety training, with more than one hand sink, and with a hand sink in the observed worker's sight. Glove use was more likely to occur in chain restaurants and in restaurants with glove supplies in food preparation areas. Hand washing and glove use were also related to each other--hand washing was less likely to occur with activities in which gloves were worn. These findings indicate that a number of factors are related to hand hygiene practices and support suggestions that food worker hand hygiene improvement requires more than food safety education. Instead, improvement programs must be multidimensional and address factors such as those examined in this study.

Systematic environmental evaluations to identify food safety differences between outbreak and nonoutbreak restaurants.

Restaurants are important settings for foodborne disease transmission. The Environmental Health Specialists Network (EHS-Net) was established to identify underlying factors contributing to disease outbreaks and to translate those findings into improved prevention efforts. From June 2002 through June 2003, EHS-Net conducted systematic environmental evaluations in 22 restaurants in which outbreaks had occurred and 347 restaurants in which outbreaks had not occurred. Norovirus was the most common foodborne disease agent identified, accounting for 42% of all confirmed foodborne outbreaks during the study period. Handling of food by an infected person or carrier (65%) and bare-hand contact with food (35%) were the most commonly identified contributing factors. Outbreak and nonoutbreak restaurants were similar with respect to many characteristics. The major difference was in the presence of a certified kitchen manager (CKM); 32% of outbreak restaurants had a CKM, but 71% of nonoutbreak restaurants had a CKM (odds ratio of 0.2; 95% confidence interval of 0.1 to 0.5). CKMs were associated with the absence of bare-hand contact with foods as a contributing factor, fewer norovirus outbreaks, and the absence of outbreaks associated with Clostridium perfringens. However, neither the presence of a CKM nor the presence of policies regarding employee health significantly affected the identification of an infected person or carrier as a contributing factor. These findings suggest a lack of effective monitoring of employee illness or a lack of commitment to enforcing policies regarding ill food workers. Food safety certification of kitchen managers appears to be an important outbreak prevention measure, and managing food worker illnesses should be emphasized during food safety training programs.

Food worker hand washing practices: an observation study.

Improvement of food worker hand washing practices is critical to the reduction of foodborne illness and is dependent upon a clear understanding of current hand washing practices. To that end, this study collected detailed observational data on food worker hand washing practices. Food workers (n = 321) were observed preparing food, and data were recorded on specific work activities for which hand washing is recommended (e.g., food preparation, handling dirty equipment). Data were also recorded on hand washing behaviors that occurred in conjunction with these work activities. Results indicated that workers engaged in approximately 8.6 work activities per hour for which hand washing is recommended. However, workers made hand washing attempts (i.e., removed gloves, if worn, and placed hands in running water) in only 32% of these activities and washed their hands appropriately (i.e., removed gloves, if worn, placed hands in running water, used soap, and dried hands) in only 27% of these work activities. Attempted and appropriate hand washing rates varied by work activity--they were significantly higher in conjunction with food preparation than other work activities (46 versus < or = 37% for attempted hand washing; 41 versus < or = 30% for appropriate hand washing) and were significantly lower in conjunction with touching the body than other work activities (13 versus > or = 27% for attempted hand washing; 10 versus > or = 23% for appropriate hand washing). Attempted and appropriate hand washing rates were significantly lower when gloves were worn (18 and 16%) than when gloves were not worn (37 and 30%). These findings suggest that the hand washing practices of food workers need to be improved, glove use may reduce hand washing, and restaurants should consider reorganizing their food preparation activities to reduce the frequency with which hand washing is needed.