“Norovirus Outbreak Associated with a Banquet at Hotel Marshfield" Marshfield, WI April 17 - 20, 2016 Final Report FBO-16-002 Wood County Health Department Riverview Clinic Building, 4th Floor 420 Dewey Street / P.O. Box 8080 Wisconsin Rapids, WI 54495 & Wisconsin Division of Public Health Bureau of Communicable Diseases Communicable Disease Epidemiology Section 1 West Wilson St., Room 272 Madison, WI 53703 1 CONTRIBUTORS PUBLIC HEALTH SUPPORT Wood County Health Department (WCHD)  Nancy Eggleston, Communicable Disease and Environmental Health Supervisor  Jean Rosekrans, Public Health Nurse  Greg Kolodziej, Environmental Health Specialist  Danielle Garski, Public Health Nurse  Kate Carlson, Environmental Health Specialist Wisconsin Department of Health Services, Division of Public Health, Bureau of Communicable Diseases (BCD), Communicable Disease Epidemiology Section (CDES)  Sarah Koske, Epidemiologist  Rachel Klos, Epidemiologist Wisconsin Division of Public Health, Bureau of Environmental and Occupational Health (BEOH), Food Safety and Recreational Licensing (FSRL)  James Mack, Food Safety Program Manager LABORATORY SUPPORT Wisconsin State Laboratory of Hygiene (WSLH)  Bacteriology Laboratory  Virology Laboratory  Tim Davis, Microbiologist 2 BACKGROUND On 4/19/2016, the Wood County Health Department (WCHD) notified the Wisconsin Division of Public Health (DPH), Communicable Diseases Epidemiology Section (CDES) of two ill individuals who had both attended a company (Company A) banquet event at the Hotel Marshfield in Marshfield, WI on 4/16/16. Onset of gastrointestinal symptoms in these individuals began early morning 4/18/2016. Appetizers, snacks, and entrees served during the event were prepared by Hotel Marshfield staff. Cupcakes were purchased from Bakery A, and cookies were provided by Company B. Leftover entrees from the banquet were boxed up immediately after the event and donated to Organization A (12 boxed meals total) where some were eaten by staff and residents of that organization. Upon recognition of a suspected outbreak, Organization A was asked by WCHD to hold the leftover food in their refrigerator and not serve it to anyone. WCHD collected a list of food and drink items served at the banquet from both the Hotel Marshfield manager and the Employee Relations Officer for Company A. CDES began creation of an investigation questionnaire, as well as an online survey to collect food and hotel exposure information from attendees. WCHD began dissemination of stool kits to ill banquet attendees and Hotel Marshfield employees to submit for laboratory testing. METHODS Surveillance Case Finding and Assessment Hotel Marshfield reported that 276 Company A employees and guests attended the banquet on 4/16/16. A Company A representative provided WCHD with a list of 21 ill banquet attendees and their contact information. These individuals were interviewed by phone by either WCHD or the DPH Surveillance and Outbreak Support (SOS) Team. During interviews, individuals were asked about others in their household who had attended the event and whether or not they were ill, and also about any other ill co-workers or friends. Names and contact information for these individuals were gathered and interviews were attempted with both ill and well individuals. A list of kitchen, banquet, bartending, and serving employees was obtained from the Hotel Marshfield. All employees listed who had worked during the three weeks prior to the banquet were asked to complete employee questionnaires. CDES created and maintained a line list of all ill and well banquet attendees, Hotel Marshfield employees, and restaurant patrons. CDES also created and maintained a listing of all Hotel Marshfield employees, their regular job duties and job duties performed the day of the banquet, and shifts worked during 4/8 – 4/18. Epidemiologic Investigation Case Definition Clinical case definition: A gastrointestinal illness characterized by vomiting and/or diarrhea and at least one additional symptom (abdominal cramps, fever, chills, fatigue, sweats, muscle aches, body aches, headache, nausea) lasting at least one day in an individual who attended, ate food from, or worked at the banquet held on 4/16/16 at Hotel Marshfield and had illness onset within 60 hours of exposure. Laboratory-confirmed case: An illness meeting the clinical case definition in an individual that had a laboratory confirmed case of norovirus infection. Probable case: An illness in an individual that meets the clinical case definition but was not tested. 3 Secondary case: A clinical case in an individual who had contact with a primary case-patient and had onset of illness more than 60 hours (one maximum incubation period) after the banquet. Questionnaire Design & Administration An investigation questionnaire was developed by CDES which gathered demographic information, information about illness and symptoms experienced, whether others at work or in the household were ill, banquet attendance, food and beverage items consumed at the banquet, overnight stay at the hotel, occupation, and any additional comments. The questionnaire was administered by phone by either WCHD staff or the SOS Team. In addition, an online survey was developed and launched by DPH to attempt to reach the approximately 250 banquet attendees for whom phone numbers were not provided. The online survey was modeled after the investigation questionnaire but did not gather any personally identifying information. The online survey was administered by DPH using Select Survey. The link to the online survey was sent to the Employee Relations Officer at Company A for distribution to their employees. Employees were asked to also have their guests complete a copy of the survey. Banquet attendees were asked to complete the survey within 24 hours. However, responses were collected for 80 hours. The survey link was not distributed to individuals who had already been interviewed by phone and respondents were asked to only complete one copy of the survey. A separate investigation questionnaire (employee questionnaire) was developed for employees of the Hotel Marshfield which gathered information about job duties, shifts worked before and after the day of the event, illness and symptoms experienced, food and beverage items consumed during the event and day of, and any additional information. Environmental Health Specialist (EHS) staff from WCHD distributed hard copies of employee questionnaires to employees of Hotel Marshfield while onsite performing inspections. This questionnaire was filled out individually by each employee. WCHD contacted the remaining employees who were not onsite at the time to attempt interviews by phone. A third questionnaire was developed for individuals reporting illness associated with dining at Libby McNeill’s, the restaurant within the Hotel Marshfield. This questionnaire gathered information about demographics, symptoms and illness, and included a list of all menu items available at the restaurant. Patrons were also asked about any modifications they made to menu items. Epidemic Curve An epidemic curve was constructed to assess the magnitude of the outbreak and likely mode of transmission. An exposure time of 6pm on 4/16/16, the time the banquet entrees were served, was used to calculate incubation periods. Analysis Case-Control Study A case-control study was conducted to evaluate the associations between food and beverage items consumed (exposures) and risk of developing illness. In both phone interviews and the online survey, banquet attendees and hotel employees were asked about consumption of a large list of food and beverage items served during the banquet on 4/16/16, or in goodie bags given to overnight guests (Appendix A). Exposure odds ratios, 95% confidence intervals, and Pearson or Fisher exact p-values were calculated using SAS 9.4. Individuals with illnesses meeting the case definition were used as cases and well individuals were used as controls in the exposure analysis. To more accurately discern associations between exposures and risk of illness, restaurant patrons, banquet attendees reporting onset of illness during or before the banquet, hotel employees, individuals whose illness did not meet the clinical case 4 definition, and individuals with onset of illness more than 60 hours after the 6pm banquet meal (likely secondary cases) were excluded from the case-control study. Laboratory Investigation Bacteriologic and Viral Testing of Human Specimens Seven stool specimens from three symptomatic banquet attendees, three Hotel Marshfield employees, and one ill restaurant patron were submitted to the Wisconsin State Laboratory of Hygiene (WSLH) to be tested for norovirus via PCR. Individuals who tested negative for norovirus were then tested for enteric bacterial pathogens and Shiga toxin. Genetic sequencing was performed on all norovirus positive specimens to identify the norovirus strain(s) present and determine if the same strain was shared among all positive specimens. Environmental Investigation Onsite Assessments Lists of food items served during the banquet event were obtained from both the hotel management and the Company A employee relations contact and compared to identify all items and where the items were prepared. A comprehensive onsite NEARS assessment was conducted during two separate visits to the hotel on 4/20/16 and 4/21/16 by Wood County Environmental Health Specialists (EHSs). During the onsite assessment the EHSs and facility management reviewed policies and procedures, observed food handling and kitchen practices, verbally reviewed menus for the banquet event with kitchen staff, and constructed a food flow. All three chefs at the hotel were interviewed by an EHS to collect information on how and by whom all banquet food items were prepared. The specifics of the preparation, including purchasing and receiving, storage, preparation, cooking, cooling, reheating, plating and serving were recorded for each food and drink item. An inspection of the kitchen and meat areas of the facility was also conducted. A list of employees and their job duties was obtained from the hotel management. Employee interview questionnaires were distributed to all employees, including kitchen staff, servers, bartenders, managers, and front desk staff. The Front of House Manager and Banquet Captain were also interviewed. Hotel employee work schedules, responsibilities on the day of the banquet, and food and drink consumed were reviewed in conjunction with their illness information. Left‐over food was collected from Organization A on 04/21/2016 and held at the Wood County Health Department for possible testing. Both Bakery A and Company B were contacted and were asked about the techniques used to prevent bare hand contact, and if there were any ill employees or complaints from customers. RESULTS Surveillance Case Finding and Assessment Interviews were completed with 151 people. Among persons who completed interviews, 55 illnesses were identified that met the case definition; five in hotel employees and 49 in banquet attendees (employees and guests). 54 illnesses were included as cases (the suspected index illness was excluded), 13 people had illnesses that did not meet the case definition, and 84 people were well. Of those 54 cases, 4 cases were laboratory-confirmed and 50 were probable cases. 51 cases were primary cases and three were secondary cases. Secondary transmission occurred within the households of banquet attendees and among hotel employees. No cases of illness meeting the case definition were identified among Libby McNeil’s restaurant patrons, other hotel guests, residents of Organization A, or attendees of other organized banquets held in the days immediately before and following the Company A’s banquet on 4/16/16. 5 Although two Libby McNeil’s restaurant patrons from separate parties became ill after meals on 4/14/16 and 4/15/16, respectively, these illnesses were determined to not be cases because one individual’s incubation period was too short to be consistent with norovirus infection, and the other tested negative for norovirus. No additional complaints of illness in the community were received from individuals who reported eating at the hotel’s restaurant. One individual from Organization A reported illness but symptoms were not consistent with norovirus infection. Epidemiologic Investigation Clinical and Descriptive Epidemiologic Features The most frequently reported signs and symptoms among the 51 primary case-patients included fatigue, diarrhea, nausea, muscle aches, body ache, abdominal cramps, vomiting, and sweating (table 1). Nineteen (35.1%) of the cases occurred in females. Case-patient age ranged from 21 to 73 years (median 53 years; n=32). Case-patients were residents of thirteen different states with the majority (38) being residents of Wisconsin. The median incubation period among primary cases was 32.5 hours (range 15 – 60 hours; n=45). The duration of illness ranged from one to nine days (median 2 days; n=41). Four individuals sought medical attention for their illness. No case-patients were seen in an emergency room or hospitalized for their illness. Table 1. Percentage of primary case-patients reporting various clinical signs and symptoms. Symptom/clinical sign No. cases N % Symptom/clinical sign No. cases N % Fatigue 51 51 100.00% Sweats 39 50 78.00% Diarrhea 50 51 Nausea 49 50 98.00% Headache 37 49 75.50% 98.00% Chills 36 51 70.60% Muscle aches 44 49 89.80% Fever 32 48 66.70% Body aches 19 22 86.40% See MD 4 51 7.80% Watery diarrhea 25 29 86.20% Bloody diarrhea 1 50 2.00% Abdominal cramps 42 50 84.00% Seen in ER 0 51 0.00% Vomiting 41 51 80.40% Hospitalized overnight 0 51 0.00% Epidemic Curve The epidemic curve of illness among case-patients with onset of illness dates during 4/17 – 4/20 (Figure 1) indicates a point-source outbreak with norovirus exposure occurring on 4/16 at approximately 6pm. Number of cases Attendees Hotel employees Secondary case 25 20 15 Index case 10 5 0 12:00 12:00 12:00 12:00 12:00 12:00 12:00 12:00 12:00 12:00 12:00 12:00 12:00 12:00 AM - PM - AM - PM - AM - PM - AM - PM - AM - PM - AM - PM - AM - PM 11:59 11:59 11:59 11:59 11:59 11:59 11:59 11:59 11:59 11:59 11:59 11:59 11:59 11:59 AM PM AM PM AM PM AM PM AM PM AM PM AM PM 4/15/16 4/16/16 4/17/16 4/18/16 4/19/16 4/20/16 4/21/16 Onset date and time 6 Figure 1. Cases of confirmed and probable norovirus gastroenteritis by 12-hour interval of onset, Wood Hotel Marshfield Banquet, 4/17/2016 - 4/20/16 (n=49). The earliest onset of symptoms occurred in a food worker who prepared food for the banquet (index case). Employee Illnesses A total of six employee illnesses were identified among Hotel Marshfield employees from completed employee questionnaires, five of which were related to this outbreak. Illnesses occurred in food workers, bartenders, and banquet servers. The earliest reported illness occurred in a chef and began less than 8 hours after the banquet meal. Other than the first illness, the onset dates and times of three employee illnesses suggests the employees were exposed at the same time as banquet attendees, while an additional employee illness with onset 4/20/16 was likely a secondary case. One employee reported illness lasting from 4/6– 4/9/16 that was unrelated to this outbreak. This individual did not work or visit the Hotel in the two weeks before the banquet and could not have introduced the virus to the facility. Analysis Case-control study The case-control study analysis was conducted using exposure information from 48 case-patients and 61 well controls. Consuming any item from the New York strip steak plate (New York strip steak with red wine reduction, buttery garlic chive mashed potatoes, and glazed carrots) was statistically associated with illness (table 2). Each item on the steak plate was also statistically significant individually. People who consumed any item from the steak plate were 2.59 times more likely to become ill than persons who did not consume an item from the steak plate (OR=2.59, 95% confidence interval 1.18-5.72, pvalue=0.0171). People who consumed New York strip steak, buttery garlic chive mashed potatoes, or glazed carrots were 2.56, 2.45, and 3.01 times more likely to be ill than persons who did not consume these items, respectively. Table 2. Attack rate table excerpt showing statistically significant exposures identified from the casecontrol study. A full list of food and drink items analyzed can be found in the Appendix. People who consumed item People who did NOT consume item Statistical Analysis Lower 95% confidence limit Upper 95% confidence limit p value Method Food/drink item Ill Well Total % Ill Ill Well Total % Ill Odds ratio Glazed carrots 23 14 37 62% 24 44 68 35% 3.01 1.31 6.91 0.0082 Pearson Any steak plate item 33 28 61 54% 15 33 48 31% 2.59 1.18 5.72 0.0171 Pearson NY strip steak Garlic chive mashed potatoes 32 25 57 56% 16 32 48 33% 2.56 1.15 5.68 0.0194 Pearson 25 18 43 58% 21 37 58 36% 2.45 1.09 5.49 0.0286 Pearson Employee Exposures The earliest onset of illness among hotel staff was reported by Chef A, who reported preparing all of the banquet food on 4/16/16. Other than Chef A, the onset dates and times of the other employee illnesses suggest they were exposed at the banquet at the same time as the attendees. One additional employee appears to be a secondary case based on his onset two days later than others. Both ill and well employees reported eating pizza ordered and made specifically for employees on the afternoon of the banquet. Both ill and well employees reported eating a variety of banquet food items. No common food or drink items were consumed by all ill employees. None of the ill employees reported 7 consuming items from the steak plate. Chef A denied eating any banquet food or pizza and only brought power bars from home. The second positive food worker, a bartender, reported drinking soda during the banquet and reported eating the pizza made specifically for the employees by the restaurant side of the kitchen earlier that day. A server who only worked the day of the banquet and became ill reported eating the pizza made for employees, having a root beer from the restaurant, and consuming ranch dressing and water with ice from the faucet in the banquet set-up area. Another ill employee (bartender) ate the employee pizza and did not consume any food during the banquet but drank a bottle of water and a Squirt soft drink. The onset of this individual’s illness on 4/20/16 suggests they were not infected at the banquet but likely from contact with a symptomatic employee or contact with a contaminated surface at work. Another ill employee did not consume any food or drink during the banquet but ordered an apple grape salad with chicken from the hotel restaurant after their shift was over. No ingredients in the salad had been prepared by staff on the banquet side of the kitchen and there were no shared ingredients used in this meal. Laboratory Investigation Bacteriologic and Viral Testing of Human Specimens On 4/26/16 the WSLH confirmed norovirus genogroup II infection from five of seven stool specimens submitted by ill individuals. Sequencing at WSLH showed five of the five norovirus positive stool specimens collected from three banquet attendees and two Hotel Marshfield employees were positive for the same norovirus strain, norovirus genogroup II.17B (Kawasaki). The two GII.17B positive specimens from Hotel Marshfield employees were submitted by Chef A and a bartender. One ill Hotel Marshfield employee and one ill restaurant patron were negative for norovirus, Shiga toxin, and enteric bacterial pathogens at WSLH. Environmental Investigation Results Facility and Event Description Hotel Marshfield is a licensed establishment that operates a banquet facility/conference center, a restaurant (Libby McNeil’s), and hotel. The hotel has a single kitchen which is divided into two halvesone half for Libby McNeil’s and one half for banquet food preparation. The halves of the kitchen are completely separate, however kitchen staff is shared between the restaurant and banquet kitchen. The banquet was held on Saturday, April 16, 2016. Food for the banquet was prepared during Thursday 4/14 through Saturday 4/16. During the banquet, food was served in three rounds. From 4-6pm, a self-service appetizer bar was available. At 6:15pm, a sit-down meal was served by banquet servers. Later in the evening at 8:30pm, a second “late night” self-service appetizer bar was available. Banquet tables were set with a house salad for each attendee, boats of ranch and French dressing, single-serve creamer and sugar, salt and pepper shakers, and a basket of dinner rolls and butter. There was an open bar offering bottled beer, wine, mixed drinks, and soft drinks. Water with ice in carafes was available on each banquet table. A plate of mixed flavor cupcakes purchased from Bakery A and plated by the Company A Employee Relations Officer was placed on each table at 6:40pm. A goodie bag of cookies from Company B was provided to overnight guests in their hotel rooms. On-site Assessment At the time of assessment, the kitchens were found to be clean and well-constructed with recent model appliances. Food items stored and maintained in refrigeration units met adequate control measures for reducing growth and survival of hazardous microorganisms. No problems were observed or reported 8 with hot holding, cold holding or cooking temperatures. Cleaning of work spaces between tasks or food items was adequate. During the assessment, the food handling practices of three chefs in the banquet kitchen were observed. When asked about the glove use policy during a verbal interview with the EHS, Chef A stated that no ready-to-eat food is touched without using gloves. However, one of the chefs was observed having bare-hand contact with ready-to-eat food items twice during the same observation period, and a member of the wait staff was observed taking and eating fried potato chips from a hot holding bowl in the kitchen. During the assessment, Chef A’s glove use consistency with ready-to-eat food could not be observed because Chef A only handled raw products which were going to be cooked at the time of the observation. No hotel employees reported illness onset in the days before the banquet. Review of employee work schedules in conjunction with their self-reported illness onset and well dates indicated that Chef A continued to work while symptomatic with norovirus infection. Review of policies with facility management revealed that the facility did not have any formal written policies regarding glove use, employee illness, or hand washing. The only written document available was an Employee Health Reporting Food Code Fact sheet the hotel uses when hiring kitchen staff which had been signed by employees. Another concern identified during the facility inspection was related to the proximity of employee restrooms to food preparation areas in the kitchen. Two restrooms for employee use were located in the kitchen area approximately 15 feet from food preparation areas. The restrooms did not have exterior self-closing doors and it did not sound like the exhaust fans were working at the time of inspection. This created a concern that aerosolized virus particles generated by toilet flushing after use by an ill employee could enter the kitchen preparation areas, pulled by the stronger exhaust fans above the ovens and grills. This could result in contamination of food and the kitchen environment. Food Flow Banquet Menu Side dishes for each entrée selection are cooked and prepared in the two days prior to the banquet. On the day of the event, the pre-prepared banquet plates are reheated to 165°F and the protein (e.g. steak, fish) is added to the reheated plate while hot. All three chefs were involved in the plating and cooling of side dishes the day(s) prior to the event. However, only Chef A prepared and plated food on the day of the banquet due to short staffing. Food prep staff is shared between the hotel restaurant and the banquet sides of the kitchen when extra help is needed by the banquet side. Salads for banquets are prepared as a team; one person prepares lettuce, one prepares tomatoes, and one prepares onions. Front of House staff add croutons and crackers, set all the banquet tables, and place prepared food in the banquet halls. No banquet leftovers were used for the restaurant. No leftover food items or garnishes are used in the hotel breakfast buffet. Food flows were constructed for all food items served. The food flow for all statistically significant food exposures is shown below. New York Strip Steaks: 1. Thursday – Retrieve steaks from cooler, cut into 10 oz. pieces, and place in container. 2. Thursday – Retrieve container from cooler, put steak seasoning on steak, and begin to pan sear on flattop. Place on sheet tray and put in banquet cooler. 9 3. Saturday – Take seared steaks from cooler, put into oven, and cook till 165°F and put on banquet plates from oven. Steak temperature is measured with a thermometer. Butter Garlic Chive Mashed Potatoes: 1. Wednesday – Peel potatoes from dry storage, cut, and place into container with water. Let sit overnight in the cooler. 2. Thursday – Take potatoes from cooler and steam for 1 hour. 3. Thursday – Put potatoes in mixing bowl with half & half, butter from dairy cooler, dried chives, salt, pepper, and garlic powder, and mix. Place mashed potatoes in 2 inch hotel pan and put in banquet cooler. 4. Friday – Place potatoes on banquet plate with carrots. 5. Saturday – Reheat plate to 165°F. Add cooked steak to plate with red wine reduction and parsley, and put in hot box. Glazed Carrots: 1. Thursday – Take carrots from cooler and steam for 10 minutes. 2. Thursday – Place cooked carrots in ice water and put into banquet cooler. 3. Friday – When needed, take and drain water and place carrots on banquet plate. 4. Saturday – Reheat plate. Squeeze honey from squirt bottle onto carrots. Red Wine Reduction: 1. Saturday – Take wine and cook in stock pot. 2. Saturday – Add water and beef stock, bring to a boil, and add corn starch. Put in hot box and ladle on steak. Garnishes: Raw parsley was freshly chopped the day of the banquet by Chef A and transferred to a bowl or shaker to later be sprinkled as garnish. Originally Chef A stated the raw parsley was chopped and transferred it to a shaker for application to the entrees. However, later Chef A stated that the parsley was sprinkled from a bowl using fingers. Chef A reported to have worn gloves during the sprinkling of the parsley. The chef stated that the parsley was used as garnish on all entrée choices. Food flows for other entrees identified parsley as a garnish on all three entrée choices. Employee Pizza Four employee pizzas were made by the front of house manager on the Libby McNeil’s side of the kitchen on 4/16- a cheese pizza, a sausage pizza, a pepperoni pizza, and a chicken bacon ranch pizza. The preparer reported using a salt and pepper shaker when making the pizzas which may have also been used for banquet prep. No ingredients prepared for the banquet food were used in the making of the pizzas. Only two pieces of pizza were left over after the employees had eaten and they were discarded. The Front of House Manager stated that everyone who was on banquet staff that evening ate some pizza. CONCLUSIONS/DISCUSSION Noroviruses are a collection of related viruses that are the most common cause of acute gastroenteritis in the United States. According to the CDC, these pathogens account for about 19-21 million illnesses per year in the U.S.1 They are also the leading cause of foodborne illness outbreaks in the U.S., most of which occur in food service settings like restaurants. These outbreaks are often due to improper 1 U.S. Centers for Disease Control and Prevention. Norovirus. Available at http://www.cdc.gov/norovirus/index.html 10 handling of food items by infected workers. However, foods such as shellfish, fruits, and vegetables may also be contaminated at their source. Norovirus infection causes acute gastroenteritis (i.e., inflammation of the stomach and/or intestines), which can lead to diarrhea, vomiting, nausea, and stomach pain. Other signs and symptoms associated with infection include fever, headaches, and body aches. Most people recover within 1 to 3 days. People can become infected through ingestion of food or water contaminated with infectious material (stool or vomit), close contact with an infected individual, or touching contaminated surfaces or objects (e.g. door handles, toilet seats). Most outbreaks of norovirus illness occur when infected people spread the virus to others. While most norovirus outbreaks occur between November - April in the U.S., people may become infected at any time of the year. Noroviruses are highly contagious, and it takes a relatively small number of virus particles—as low as 18—to make someone sick.2 People with norovirus shed the virus in very high concentrations in the stool and vomit (millions of viral particles per gram3). Infected individuals are most contagious while they are having symptoms and during the first few days of recovery. However, norovirus particles may be present in an infected person’s vomit and/or stool before they even feel sick (up to 30% of norovirus infections are asymptomatic4), and they can remain in the stool for up to 2 weeks after recovery.5,6 Food service workers, health care providers and workers, and those who attend or work in daycare settings should not return to work until after they have been symptomfree for 48 hours. This investigation identified a foodborne outbreak of norovirus gastroenteritis associated with consuming food from a banquet event held at the Hotel Marshfield banquet facility in Marshfield, WI on 4/16/2016. The causative agent was Norovirus genogroup II.17B (Kawasaki). Confirmed and probable cases were identified among banquet attendees and employees of Hotel Marshfield. Based on the epidemiologic, laboratory, and environmental evidence gathered during this outbreak, improper food handling by a Hotel Marshfield employee who was infected with norovirus is the most likely cause of this outbreak. Because specific food items were identified that were associated with higher risk of illness and all of these items were served on the same plate, this suggests the ill employee was a chef rather than a server or bartender. The challenge of being short-staffed in the banquet kitchen on the day of the banquet may have contributed to a breakdown in hand hygiene or glove use. The pattern of illness onset dates and times in the epidemic curve supports the conclusion that exposure to the virus occurred at the same time among banquet attendees and hotel staff. This means that the virus was not introduced to the hotel by an ill banquet attendee. Although one banquet attendee reported becoming ill during the event, the epidemic curve indicates a point source exposure consistent with a foodborne outbreak, rather than the pattern of illnesses typically seen with person-to-person transmission from an ill attendee. Since ill attendees do not come in contact with kitchen staff, outbreaks where both food workers and attendees are ill at the same time generally indicate the food worker was the source, rather than a victim. 2 Teunis PF, Moe CL, Liu P, et al. Norwalk virus: how infectious is it? J Med Virol 2008;80:1468--76. Atmar RL, Opekun AR, Gilger MA, et al. Norwalk virus shedding after experimental human infection. Emerg Infect Dis. 2008;14:1553--7. 4 Hall A, Vinjé J, Lopman B, et al. Norovirus Outbreak Management and Disease Prevention Guidelines. MMWR. March 4, 2011/60(RR03);1-15. 5 U.S. Centers for Disease Control and Prevention. Norovirus Transmission. Available at http://www.cdc.gov/norovirus/about/transmission.html 6 Guo Z, Huang J, Shi G, et al. A food-borne outbreak of gastroenteritis caused by norovirus GII in a university located in Xiamen City, China. Intl J of Infectious Dis, Vol. 28;101 – 106. 3 11 Additionally, the same strain of norovirus, norovirus GII.17B (Kawasaki) was isolated from both food workers and banquet attendees. The Kawasaki strain is a rare strain of norovirus only recently introduced to the United States in the last five years.7 In Wisconsin, it tends to be associated with foodborne outbreak settings rather than person-to-person transmission in the community; during 20152016, 62.5% of the outbreaks caused by the Kawasaki strain in Wisconsin were foodborne.8 The rarity of the strain, its recovery from both employees (including Chef A) and attendees, and the fact that the same strain was identified in all norovirus positive specimens support the conclusion the illnesses were all acquired from a single source. Chef A reported illness onset at 1:45am on the night of the banquet (4/16/16) while the majority of other illnesses began in the evening of the next day. The length of Chef A’s incubation period (time between exposure and start of symptoms) was 7.75 hours, which is shorter than the range of 10‐50 hours observed during volunteer studies of norovirus infection where exact time of exposure is known,9,10 as well as the median incubation period length of 32.5 hours observed in this outbreak. Assuming the onset date and time of Chef A’s illness was accurately reported, this indicates Chef A was likely exposed to the virus 1-2 days prior to the banquet (not at the same time as banquet attendees and other staff). Although Chef A’s symptoms did not begin until after the banquet was over, shedding of norovirus in the stool of infected asymptomatic individuals has been documented11 and it was likely Chef A was shedding virus at the time he/she was preparing and plating the food for the banquet. Additionally, carriage and shedding of norovirus has been documented in individuals who never develop symptoms.12 It is also possible that an unidentified asymptomatic shedding employee could have served as a source of contamination during food prep, or that an ill employee did not accurately disclose his/her illness status and onset date/time. While Front of House staff were involved in adding croutons to salads, none of these items were statistically associated with illness. Only items that were prepared and finished in the kitchen were statistically associated with illness, increasing the likelihood the contamination event occurred during banquet meal preparation. If a banquet server was the source, we would expect to see no statistically significant association with a specific food item because all types of entrée plates would be handled by the ill individual. Results of the case-control study showed that individuals who consumed the New York strip steak (served with a red wine reduction), buttery garlic chive mashed potatoes, and glazed carrots were more than two times more likely to become ill than those who did not. These three items were plated together on the same plate. A significant statistical association with illness existed for each item individually and for all three items combined. No other food or beverage items were statistically associated with illness. The fact that all food items with a significant association with illness were cooked items (except the chopped parsley garnish and honey glaze) suggests that contamination occurred after the items were cooked. Foodborne norovirus outbreaks commonly involve food items that are handled and served raw, such as salads and fruit. The only raw ingredients on the steak plates reported by the establishment were chopped fresh parsley used as garnish and the honey squeezed onto the carrots 7 Parra GI, Green KY. Genome of emerging norovirus GII.17, United States, 2014. Emerg Infect Dis. 2015 Aug [accessed 8/1/2016]. Wisconsin Department of Health Services, unpublished data. 9 Dolin R, Blacklow NR, DuPont H, et al. Transmission of Acute Infectious Nonbacterial Gastroenteritis to Volunteers by Oral Administration of Stool Filtrates. J Infect Dis. 1971. 123(3):307-312. 10 Lee RM, Lessler J, Lee RA, et al. Incubation periods of viral gastroenteritis: a systematic review. BMC Infectious Diseases. 2013;13:446. doi:10.1186/1471-2334-13-446. 11 Hall A, Vinjé J, Lopman B, et al. Norovirus Outbreak Management and Disease Prevention Guidelines. MMWR. March 4, 2011/60(RR03);1-15. 12 Hall A, Vinjé J, Lopman B, et al. Norovirus Outbreak Management and Disease Prevention Guidelines. MMWR. March 4, 2011/60(RR03);1-15. 8 12 after reheating. Since the chef stated that the same parsley was used as garnish for all three entrees, if the parsley was contaminated at its source (in the field), we would expect to see no statistically significant food item, since all entrees would have contained the same parsley. However, the fact that only the steak plate was statistically associated with illness suggests contamination by food worker during kitchen prep is more likely than contamination in the field. Contamination could have been introduced if parsley was chopped while wearing gloves, but then added to the steak plates by an ungloved hand. Alternatively, the parsley may have only been added to the steak plates. Also, contamination could have also been introduced if the honey squeeze bottle or bottle nozzle was contaminated with norovirus. Although no additional illnesses were reported among attendees of subsequent banquets, one secondary case occurred in an employee, suggesting person-to-person transmission or transmission from contact with contaminated environmental surfaces also occurred among staff the day after the banquet. Chef A continued to work the next couple days while symptomatic with diarrhea and could have contaminated surfaces or transferred the virus via contact, serving as the source of infection for the secondary case identified among staff. Hotel employees with primary cases who became ill but did not consume banquet food may have been exposed to contaminated food during serving, table clearing, or cleaning, or to contaminated surfaces such as tables in kitchen prep areas, sinks, bathrooms, or door handles. Several contributing factors were identified during this outbreak investigation, and multiple violations of Wisconsin Food Code which could contribute to the likelihood of an outbreak occurring were observed during the on-site assessments conducted by WCHD sanitarians. Bare-handed contact of ready-to-eat food items by food workers was observed multiple times during the same visit, suggesting that barehanded contact occurs frequently during routine food prep activities at the facility. The facility did not have any formal written employee illness, hand washing, or glove use policies. Review of the employees’ work schedules in conjunction with their illness onset and resolution dates indicated that Chef A worked preparing food for more banquets at the facility while symptomatic with diarrhea, which violates Wisconsin Food Code. Additionally, hotel employee restrooms did not have functioning fans and are located near (approx. 15ft) food preparation areas. While the case-control study results point to contamination of specific food items as the source of illness during this outbreak, the close proximity of the employee bathrooms to prep areas could contribute to kitchen contamination and future outbreaks. RECOMMENDATIONS According to the CDC, while there is no vaccine to prevent norovirus infection, illness can be prevented through proper hand hygiene; washing fruits and vegetables and cooking seafood thoroughly before consuming; avoiding food preparation and caring for others when sick; cleansing and disinfecting contaminated surfaces; and carefully washing laundry. Individuals who work in the food service industry should be aware of practices that can prevent the spread of noroviruses: • not preparing food for others when sick and for at least 48 hours after symptoms stop, • practicing proper hand hygiene, • rinsing fruits and vegetables and cooking shellfish, • regularly cleaning and sanitizing kitchen utensils, counters, and surfaces, and • carefully washing table linens, napkins, and other laundry. 13 It is particularly important for food establishment employees to inform their manager when they are ill and to not work while sick with gastroenteritis and for at least 48 hours following recovery. Complying with this recommendation means that employees need to be both aware of it and have the motivation and responsibility to comply with it. The following recommendations were developed for Hotel Marshfield following the assessment conducted on 4/20 and 4/21/2016: • Review internal procedures regarding employee illness, glove use, and hand washing to ensure they are consistent with standard food safety regulations, and create written policies outlining these procedures. • Review and update sick leave policy for management and employees. • All personnel, including management, should undergo comprehensive food handling training that includes at a minimum: personal hygiene, proper use of disposable gloves, and employee illness policies to ensure complete understanding.  Consider installing negative pressure ceiling fans in employee restrooms to minimize movement of aerosolized particles into the kitchen, or, discontinue use of the employee restrooms in the kitchen area. As a result of these recommendations, the hotel has reviewed their procedures for reporting illness, glove use, and hand washing with all staff. The sick leave policy has been reviewed with all staff, and the fact that all staff that earn paid time off (sick leave) has been reinforced. The WCHD conducted an onsite food safety training at Hotel Marshfield that discussed personal hygiene, glove use, and employee illness, as well as other risk factors for foodborne illness. The information provided during the training presentation and via brochures has been incorporated into the hotel’s employee training program. The employee restroom fans were verified operational (low-flow, constant-on fans) and the employee restroom doors have had spring hinges installed to self-close and keep closed. Ready-to-use spray bottles of bleach solution have been added as an additional option for sanitizing in the kitchen. APPENDIX Table 3. Line List of case-patients (identifying information of hotel staff has been removed). Onset date Onset time (24:00) IP (hrs) N V D BD 4/17/2016 1:45 7.75 Y Y Y N M 4/17/2016 9:00 15.00 Y Y Y N M 4/17/2016 16:00 22.00 N N Y N F 4/17/2016 16:00 22.00 Y Y Y N 59 M 4/17/2016 17:00 23.00 Y Y Y N 51 M 4/17/2016 19:00 25.00 Y Y Y F 4/17/2016 19:30 25.50 Y Y Y F 4/17/2016 20:00 26.00 Y Y F 4/17/2016 22:00 28.00 Y N Class Case type Affiliation Conf INDEX HE 1 Prob 1° A 57 2 Prob 1° A 57 3 Prob 1° A 4 Prob 1° A 5 Prob 1° A 6 Prob 1° A 7 Conf 1° A 8 Prob 1° A No. Age 21 Sex 14 WD AC HA MA BA CH SW FE FA MD Y Y Y Y Y Y Y Y N Y Y N N N Y Y Y N Y N Y N N N N Y N Y Y N Y Y Y Y N Y Y Y N Y N Y N N Y N Y Y Y Y Y N N Y Y Y N N N N Y N Y N Y Y Y Y Y Y Y Y Y Y N Y Y Y Y Y Y Y N Y Y N 9 Prob 1° A M 4/17/2016 22:00 28.00 Y Y Y N 10 Prob 1° A 34 11 Prob 1° A 12 Prob 1° A 13 Prob 1° A 14 Conf 1° HE 15 Prob 1° A 16 Prob 1° A 17 Prob 1° F 4/17/2016 22:30 28.50 Y Y Y N 61 F 4/17/2016 23:00 29.00 Y Y Y 28 M 4/17/2016 23:00 29.00 Y Y Y 67 M 4/17/2016 23:00 29.00 Y Y Y 4/17/2016 23:00 29.00 Y Y Y M 4/17/2016 23:59 29.98 Y Y Y N 23 F 4/17/2016 Y Y Y N A 73 F 4/17/2016 Y Y Y N 18 Prob 1° A 48 M 4/17/2016 Y Y Y N 19 20 Prob 1° A 51 M 4/18/2016 0:00 30.00 Y Y Y N Prob 1° A M 4/18/2016 0:00 30.00 Y Y Y N 21 Prob 1° A M 4/18/2016 0:30 30.50 Y Y Y N Y 22 Prob 1° A F 4/18/2016 1:00 31.00 Y Y Y N Y N Y 23 Prob 1° HE 4/18/2016 1:30 31.50 Y Y Y N Y N Y 24 Prob 1° A 42 M 4/18/2016 2:00 32.00 Y Y Y N Y Y Y 25 Prob 1° A 37 M 4/18/2016 2:00 32.00 Y Y N Y Y 26 Prob 1° A M 4/18/2016 2:30 32.50 Y N Y N Y 27 Conf 1° A F 4/18/2016 3:00 33.00 Y Y Y N Y 28 Conf 1° A M 4/18/2016 3:15 33.25 Y N Y N N 29 Prob 1° A F 4/18/2016 3:25 33.42 Y Y Y N Y Y 30 Prob 1° A F 4/18/2016 4:00 34.00 Y Y N N 31 Prob 1° A M 4/18/2016 4:00 34.00 N Y 32 Prob 1° A F 4/18/2016 4:30 34.50 Y Y 33 Prob 1° A M 4/18/2016 7:00 37.00 Y 34 Prob 1° A M 4/18/2016 7:00 37.00 35 Prob 1° HE 4/18/2016 7:00 36 Prob 1° A F 4/18/2016 7:00 37 Prob 1° A M 4/18/2016 38 Prob 1° A 44 M 39 Prob 1° A 54 40 Prob 1° A 41 Prob 1° A 42 Prob 1° A 43 Prob 1° A 44 Prob 1° A 45 Prob 1° A 46 Prob 1° A 47 Prob 1° 48 Prob 49 Prob pm Y Y Y Y Y N Y N Y Y Y Y N Y Y Y Y N Y N Y Y Y Y Y Y Y Y Y N Y Y Y Y N Y N Y N N N N Y N Y Y Y Y N N N Y Y N N Y N Y N Y Y Y Y N Y Y Y Y N Y N Y Y N N Y Y N N Y N N N N Y Y N Y N N Y Y N Y Y Y Y N N Y N N N Y Y N N Y N Y N Y Y Y N Y N Y Y Y Y Y N Y Y Y Y Y N Y Y Y Y Y Y N N Y Y Y Y Y Y N Y Y Y Y Y Y Y N N N Y Y N Y Y N Y Y Y Y Y Y N Y Y Y Y Y N N Y Y Y Y Y N Y N Y N Y Y Y Y Y Y N Y Y N Y Y Y Y Y N Y N N N Y N N Y Y Y Y Y Y Y 37.00 Y Y Y N Y N Y Y N Y N N Y 37.00 Y Y Y N Y Y Y Y Y Y Y Y N 7:00 37.00 N N Y N N N N N N N N N N 4/18/2016 8:00 38.00 Y Y N N Y Y Y Y Y Y Y N M 4/18/2016 10:00 40.00 Y Y Y N Y Y Y Y N N N Y N 60 F 4/18/2016 12:00 42.00 Y N Y N Y Y Y Y N Y Y Y N 62 M 4/18/2016 12:00 42.00 Y Y Y N Y Y Y Y Y Y Y Y N M 4/18/2016 12:00 42.00 Y N Y N N Y Y N N N Y N 40 M 4/18/2016 16:30 46.50 Y Y Y N Y Y Y Y Y Y Y Y N 61 M 4/18/2016 22:00 52.00 Y Y Y N Y Y Y Y Y Y Y Y Y F 4/18/2016 23:59 53.98 Y Y N N Y Y N Y Y Y Y N 57 M 4/18/2016 Y N Y N Y Y Y Y Y Y Y Y N A 58 M 4/18/2016 Y N Y Y Y Y Y Y Y N Y Y N 1° A 33 M 4/18/2016 Y Y Y N Y Y Y Y Y Y Y Y N 1° A 33 M 4/19/2016 Y Y Y N Y Y Y Y Y Y Y Y N 59 61 2:00 56.00 15 Y N Y Y Y 50 Prob 1° A 56 M 4/19/2016 3:00 57.00 Y Y N N N N N N N Y N N N 51 Prob 1° A 54 M 4/19/2016 6:00 60.00 Y Y Y N N Y Y Y Y Y Y Y N 52 Prob 2° HE N N Y N Y N Y N N N Y N 53 Prob 2° A 32 F 4/20/2016 11:30 65.50 Y Y Y N Y Y Y Y Y N Y Y N 54 Prob 2° A 48 M 4/20/2016 Y Y Y N Y Y Y Y Y Y Y Y N 4/20/2016 Y M/F=Male/Female; Conf=Confirmed case, Prob=Probable case; 1°=Primary case, 2°=Secondary case; Affiliation A=Attendee, HE=Hotel employee; IP=Incubation period; N=Nausea; V=Vomiting; D=Diarrhea; BD=Bloody diarrhea; WD=Watery diarrhea; AC=Abdominal cramps; FE=Fever; CH=Chills; SW=Sweats; ; HA=Headache; MA=Muscle aches; FA=Fatigue; MD=Saw a physician for this illness. Table 4. Complete Attack Rate Table from Case-Control Study People who consumed item People who did NOT consume item Statistical Analysis Lower 95% confidence limit Upper 95% confidence limit p value Method Food/drink item Ill Well Total % Ill Ill Well Total % Ill Odds ratio glazedcarrots_2 23 14 37 62% 24 44 68 35% 3.01 1.31 6.91 0.0082 Pearson anysteakplate 33 28 61 54% 15 33 48 31% 2.59 1.18 5.72 0.0171 Pearson NYstripsteak 32 25 57 56% 16 32 48 33% 2.56 1.15 5.68 0.0194 Pearson Garlicchivemashedpotatoes 25 18 43 58% 21 37 58 36% 2.45 1.09 5.49 0.0286 Pearson Mashedpotatoes 16 29 45 36% 32 31 63 51% 0.53 0.24 1.17 0.1161 Pearson Wine 4 11 15 27% 44 48 92 48% 0.4 0.12 1.34 0.1265 Pearson Creammilkincoffeetea 7 16 23 30% 39 42 81 48% 0.47 0.18 1.27 0.1312 Pearson anyporkplate 19 33 52 37% 29 28 57 51% 0.56 0.26 1.2 0.132 Pearson BlackForestchocolate 21 17 38 55% 27 40 67 40% 1.83 0.82 4.09 0.1391 Pearson Ranchdressing Salmonwlemondillcreamsa uce 30 30 60 50% 16 29 45 36% 1.81 0.82 4.01 0.1399 Pearson 9 18 27 33% 38 40 78 49% 0.53 0.21 1.31 0.1659 Otherentreeorsidedish 6 3 9 67% 39 55 94 41% 2.82 0.56 18.3 0.174 Pearson Fisher's exact Swedishmeatballs 9 6 15 60% 37 51 88 42% 2.07 0.68 6.31 0.196 Pearson Strawberries 5 11 16 31% 42 47 89 47% 0.51 0.16 1.58 0.2378 Pearson Greenbeansalmandine 12 20 32 38% 36 37 73 49% 0.62 0.26 1.44 0.2633 Pearson Mixeddrinks 11 19 30 37% 36 38 74 49% 0.61 0.26 1.46 0.266 Pearson Gravy 12 20 32 38% 36 38 74 49% 0.63 0.27 1.48 0.2898 Pearson Crackers 5 10 15 33% 42 46 88 48% 0.55 0.17 1.73 0.3009 Pearson Frenchdressing 18 28 46 39% 28 29 57 49% 0.67 0.3 1.46 0.3105 Pearson Iceinanydrinks 31 42 73 42% 17 15 32 53% 0.65 0.28 1.5 0.3129 Pearson Cherrymapleporkloin 11 19 30 37% 37 41 78 47% 0.64 0.27 1.52 0.3131 Pearson Stuffedmushroomcaps 5 10 15 33% 41 46 87 47% 0.56 0.18 1.78 0.3214 Pearson Bruschetta 10 8 18 56% 37 49 86 43% 1.66 0.6 4.6 0.3313 Pearson anylatenight 18 26 44 41% 24 23 47 51% 0.66 0.29 1.52 0.3315 Pearson Dicedgarlicredpotatoes 12 21 33 36% 33 38 71 46% 0.66 0.28 1.54 0.3325 Chickenwings 3 8 11 27% 42 47 89 47% 0.42 0.07 1.91 0.3364 Pearson Fisher's exact Carrots 9 7 16 56% 37 48 85 44% 1.67 0.57 4.9 0.3486 Pearson 16 anysalmonplate 15 24 39 38% 33 37 70 47% 0.7 0.32 1.56 0.3815 Pearson Sodasoftdrinkpop 15 14 29 52% 33 45 78 42% 1.46 0.62 3.44 0.384 Celery 2 5 7 29% 44 50 94 47% 0.45 0.04 2.97 0.4501 Pearson Fisher's exact Asparagus 12 19 31 39% 35 40 75 47% 0.72 0.31 1.69 0.4532 Pearson Butter 32 34 66 48% 16 23 39 41% 1.35 0.61 3.01 0.4585 Bottledwater 3 6 9 33% 44 51 95 46% 0.58 0.09 2.92 0.5076 Pearson Fisher's exact anyappetizer 10 15 25 40% 37 41 78 47% 0.74 0.3 1.85 0.516 Pearson Fruitplatter 6 10 16 38% 42 49 91 46% 0.7 0.23 2.09 0.521 Pearson Beer 24 26 50 48% 24 33 57 42% 1.27 0.59 2.73 0.5407 Pearson Otherappetizer 7 6 13 54% 41 49 90 46% 1.39 0.43 4.48 0.5754 Pearson Tortillachips Leftoverstrawberrycheesec ake 10 10 20 50% 38 50 88 43% 1.32 0.5 3.48 0.5796 2 1 3 67% 42 54 96 44% 2.57 0.13 154.46 0.5834 Ranchdippingsauce 2 1 3 67% 44 54 98 45% 2.45 0.12 147.44 0.5901 Pearson Fisher's exact Fisher's exact Dinnerrolls 38 45 83 46% 10 15 25 40% 1.27 0.51 3.14 0.61 Pearson Stawberrycheesecake 12 16 28 43% 35 38 73 48% 0.81 0.34 1.96 0.6463 Pearson Fisher's exact Tomatoes 3 2 5 60% 43 51 94 46% 1.78 0.19 22.09 0.661 anybaritem 43 53 96 45% 5 8 13 38% 1.3 0.4 4.26 0.6661 Honeydewmelon 2 4 6 33% 45 55 100 45% 0.61 0.05 4.51 0.691 Cauliflower 4 3 7 57% 41 49 90 46% 1.59 0.25 11.45 0.701 Chipsforartichokedip 8 8 16 50% 40 49 89 45% 1.23 0.42 3.55 0.7086 Housesalad 45 54 99 45% 3 6 9 33% 1.67 0.33 10.83 0.7283 Pineapple 3 5 8 38% 44 53 97 45% 0.72 0.11 3.97 0.7286 anyrawveg 45 55 100 45% 3 5 8 38% 1.36 0.25 9.23 0.7305 Pearson Fisher's exact Fisher's exact Fisher's exact Coffee 20 26 46 43% 28 32 60 47% 0.88 0.41 1.9 0.7438 Pearson Cheese 9 10 19 47% 38 49 87 44% 1.16 0.43 3.14 0.7693 Pearson Waterfromcarafeontable 32 41 73 44% 15 17 32 47% 0.88 0.38 2.04 0.7731 Pearson Spinachartichokedip 6 8 14 43% 41 47 88 47% 0.86 0.28 2.68 0.7946 Pearson Milk 6 6 12 50% 42 49 91 46% 1.17 0.35 3.89 0.8018 Pearson Pearson Fisher's exact Fisher's exact Tacodip 8 9 17 47% 40 50 90 44% 1.11 0.39 3.14 0.8424 Pearson Carrotcake 10 11 21 48% 38 46 84 45% 1.1 0.42 2.87 0.8447 Pearson any_cupcake 29 36 65 45% 12 16 28 43% 1.07 0.44 2.63 0.8755 Pearson Cupcakes 35 43 78 45% 13 17 30 43% 1.06 0.46 2.49 0.8854 Pearson Sausage Cheesesausagecrackerplatt er 8 10 18 44% 39 46 85 46% 0.94 0.34 2.62 0.9114 Pearson 9 11 20 45% 38 45 83 46% 0.97 0.36 2.58 0.9497 Leftoverblackforestchoc 2 2 4 50% 42 53 95 44% 1.26 0.09 18.04 1 Leftovercupcakes 2 2 4 50% 42 53 95 44% 1.26 0.09 18.04 1 Vegetableplatter 5 6 11 45% 37 47 84 44% 1.06 0.24 4.53 1 Grapes 4 5 9 44% 43 53 96 45% 0.99 0.18 4.9 1 Water 11 5 16 69% 7 3 10 70% 0.94 0.11 6.89 1 Pearson Fisher's exact Fisher's exact Fisher's exact Fisher's exact Fisher's exact 17 Dilldip 3 4 7 43% 43 51 94 46% 0.89 0.12 5.58 1 Broccoli 2 3 5 40% 43 52 95 45% 0.81 0.06 7.39 1 Cantaloupe 4 6 10 40% 43 51 94 46% 0.79 0.15 3.59 1 anycookie 2 3 5 40% 45 51 96 47% 0.76 0.06 6.93 1 Cookies Chocolatetoffeeteasercooki e 1 2 3 33% 47 54 101 47% 0.57 0.01 11.42 1 1 0 1 100% 47 57 104 45% U U U U Otherappetizersnack 1 0 1 100% 44 53 97 45% U U U U Otherbeverages 2 0 2 100% 17 8 25 68% U U U U anyrawfruit 47 57 104 45% 0 0 0 0% U U U U Otherfruit 0 0 0 0% 48 56 104 46% U U U U Othervegetable 0 0 0 0% 45 53 98 46% U U U U Pastaprimavera 0 0 0 0% 47 57 104 45% U U U U BBQdippingsauce 0 2 2 0% 45 51 96 47% U U U U Buffalodippingsauce 0 2 2 0% 46 53 99 46% U U U U Caramelapplecookie 0 1 1 0% 48 55 103 47% U U U U Chocolateexplosioncookie 0 1 1 0% 47 54 101 47% U U U U Peanutbuttermeltscookie 0 1 1 0% 47 55 102 46% U U U U Leftovercarrotcake 0 1 1 0% 45 54 99 45% U U U U Othercheeseplatteritem 0 1 1 0% 48 53 101 48% U U U U Otherdessertitem 0 1 1 0% 48 53 101 48% U U U U U=undefined value (0 value in at least one cell precludes analysis) 18 Fisher's exact Fisher's exact Fisher's exact Fisher's exact Fisher's exact Attendee investigation questionnaire (company identifying information has been redacted): Investigation Questionnaire v2 DEMOGRAPHIC INFORMATION Name: Age: Gender: M F Parent/Guardian Name: Address: City: County: State: Phone (home): Zip: Phone (cell): Occupation: High risk activities:  Daycare  Food handler  Health care provider/worker (Provide appropriate exclusion and education if individual is ill / was ill) Did you attend the Roehl Transportation Dinner Event at Hotel Marshfield on Saturday April 16, 2016 in Marshfield, WI? Yes / No Did anyone else in your household attend the Roehl Transportation Dinner Event? Yes / No Name: ______________________________________________ Phone Number: ______________________________________ Name: ______________________________________________ Phone Number: ______________________________________ Did you stay overnight at the Hotel Marshfield before or after the dinner event? Yes / No If yes, please provide dates of stay: ________________________________________________________ CLINICAL INFORMATION Have you been ill with gastrointestinal symptoms (diarrhea, abdominal cramping, vomiting, nausea, etc.) anytime during the last two weeks (approximately April 5th to present)? Y N If no skip to Other Ill Persons Onset Date: ____ / ____ / ____ Onset Time: Well Date: ____ / ____ / ____ Well Time: ____:____ AM Nausea Y N Vomiting Bloody diarrhea Y N Chills Y Body aches Other: Y ____:____ AM PM □Still ill at time of interview PM N Diarrhea Abdominal cramps Y N Fever (_____o) Y N N Sweats Y N Headache Y N Y N Muscle aches Y N Fatigue Y N Y N Did you see a physician? Y N Date: ____ /____/ ____ Were you seen in an ER/ED Y N Where: Were you hospitalized overnight? Y N Where: Was a stool specimen collected? Y N Results: If no stool specimen collected, would you be willing to submit a stool specimen for free testing? Y Y N (defined as 3 or more loose stools 24 hours) N Daytime contact number if different from above: ______________________________________________________ OTHER ILL PERSONS Has anyone in your household been ill with GI symptoms during the last two weeks? Y N 19 1) If yes, who: _______________________________________ Onset date: ____ / ____ / ____ Time: ____:____ AM PM What were their symptoms(circle)? Nausea / Vomiting / Diarrhea / Abd. cramps / Fever / Headache / Other: ________________ Did this person attend the Roehl Transport Dinner Event? Yes / No 2) If yes, who: _______________________________________ Onset date: ____ / ____ / ____ Time: ____:____ AM PM What were their symptoms(circle)? Nausea / Vomiting / Diarrhea / Abd. cramps / Fever / Headache / Other: ________________ Did this person attend the Roehl Transport Dinner Event? Yes / No Do you know anyone else (friend, co-worker, etc.) who was ill with GI symptoms during this same time period? Y 1) If yes, who: _______________________________________ When/Onset: ____ / ____ / ____ What were their symptoms(circle)? Nausea / Vomiting / Diarrhea / Abd. cramps / Fever / Headache / Other: ________________ Did this person attend the Roehl Transport Dinner Event? Y / N-- > If yes, contact number:__________________________ 2) If yes, who: _______________________________________ When/Onset: ____ / ____ / ____ What were their symptoms(circle)? Nausea / Vomiting / Diarrhea / Abd. cramps / Fever / Headache / Other: ________________ Did this person attend the Roehl Transport Dinner Event? Y / N-- > If yes, contact number:__________________________ EXPOSURES Did you eat any food or have anything to drink at the Roehl Transport Dinner Event? Yes / No Food Item Yes/No Details APPETIZERS (served 4- 6 p.m.) Layered taco dip Y N Unk Y N Unk Y N Unk Honeydew melon Y N Unk Cantaloupe Y N Unk Pineapple Y N Unk Tortilla chips Fruit platter Grapes Y N Unk Strawberries Y N Unk Other fruit Y N Unk Bruschetta Y N Unk Baked spinach & artichoke dip Y N Unk Y N Unk Y N Unk Chips for artichoke dip Other appetizer Specify: Specify: DINNER ITEMS House salad Y N Unk Ranch dressing Y N Unk French dressing Y N Unk Dinner rolls Y N Unk Butter Y N Unk Salmon with lemon dill cream sauce Y N Unk Steamed asparagus Y N Unk Diced garlic red potatoes Y N Unk 20 N Cherry maple pork loin w/ cherry sauce Y N Unk Mashed potatoes Y N Unk Gravy Y N Unk Green beans almandine Y N Unk New York strip steak w/ red wine sauce Y N Unk Garlic chive mashed potatoes Y N Unk Honey glazed carrots Y N Unk Pasta primavera Y N Unk Other entrée or side dish: Y N Unk Y N Unk Black Forest chocolate Y N Unk Carrot cake Y N Unk Strawberry cheesecake (white) Y N Unk Y N Unk Specify: DESSERT Cupcakes Cookies (for overnight guests) Caramel apple Y N Unk Chocolate Toffee Teasers Y N Unk Chocolate explosion Y N Unk Peanut butter melts Y N Unk Y N Unk Y N Unk Water from carafe on table Y N Unk Bottled water Other dessert item Specify: BEVERAGES (throughout the night) Water Y N Unk Soda/soft drinks/pop Y N Unk Hot tea Y N Unk Coffee Y N Unk Y N Unk Milk Y N Unk Beer Y N Unk Specify: Wine Y N Unk Specify: Mixed drink(s) Y N Unk Specify: Other beverage(s) Y N Unk Specify: Was there ice in any of your drinks? Y N Unk Y N Unk Cheese Y N Unk Sausage Y N Unk Crackers Y N Unk Other platter item Y N Unk Y N Unk Carrots Y N Unk Broccoli Y N Unk Cream/Milk in coffee or tea Specify: LATE NIGHT APPETIZERS/SNACKS served at 8:30 p.m. Cheese/sausage/cracker platter Vegetable platter Specify: 21 Cauliflower Y N Unk Tomatoes Y N Unk Celery Y N Unk Other vegetable Y N Unk Dill dip Y N Unk Chicken wings Y N Unk Buffalo dipping sauce Y N Unk BBQ dipping sauce Y N Unk Ranch dipping sauce Y N Unk Swedish meatballs Y N Unk Stuffed mushroom caps with sausage stuffing Y N Unk Cupcakes (leftover) Y N Unk Black Forest chocolate Y N Unk Carrot cake Y N Unk Strawberry cheesecake (white) Y N Unk Y N Unk Other appetizer/snack Specify: Specify: Choose one:  My table was among the first to be served (~ first 25%) Which of the following best describes when your table went through the food line/received food?  My table was among the last to be served (~ last 25%)  My table was served about midway through (~middle 50%) Did you witness anyone vomiting or see evidence of any vomiting accident? Yes / No If yes, where and when did you hear/see anyone vomiting? ____________________________________________________________________________________________________________ Additional Comments: Thank you very much for your time!! Employee Investigation Questionnaire: Investigation Questionnaire Hotel Marshfield Employees DEMOGRAPHIC INFORMATION Employee Name: Age: Gender: M F Address: City: Phone (home): County: State: Zip: Phone (cell): Job Duties/Position: WORK HISTORY How long have you worked at this establishment? years / months / days (circle one) 22 Do you work at any other food establishments? If yes, where? N Name: Do you work anywhere else? If yes, where? Y Address: Y N Name: Address: Did you work on: Fri, Apr 8: Y N If yes, shift: Duties: Sat, Apr 9: Y N If yes, shift: Duties: Sun, Apr 10: Y N If yes, shift: Duties: Mon, Apr 11: Y N If yes, shift: Duties: Tues, Apr 12: Y N If yes, shift: Duties: Weds, Apr 13: Y N If yes, shift: Duties: Thurs, Apr 14: Y N If yes, shift: Duties: Fri, Apr 15: Y N If yes, shift: Duties: Sat, Apr 16: Y N If yes, shift: Duties: Sun, Apr 17: Y N If yes, shift: Duties: Mon, Apr 18: Y N If yes, shift: Duties: _________ CLINICAL INFORMATION Have you been ill with gastrointestinal symptoms (vomiting, diarrhea, abdominal cramping, nausea, etc.) in the last 2 weeks? Y N If no skip to Other Ill Persons Onset Date: ____ / ____ / ____ Onset Time: ____:____ AM PM Well Date: ____ / ____ / ____ Well Time: ____:____ AM PM  Still symptomatic at time of interview Nausea Y N Vomiting Y N Diarrhea Y N (3 or more loose stools 24 hours) Bloody diarrhea Y N Abdominal cramps Y N Fever (_____o) Y N Chills Y N Sweats Y N Headache Y N Body aches Y N Muscle aches Y N Fatigue Y N Other: Y N Did you see a physician? ______________________________________________________ Y Were you seen in an ER/ED Y N Where: Were you hospitalized overnight? Y N Where: Was a stool specimen collected? Y N Results: N Date: ____ /____/ ____ OTHER ILL PERSONS Has anyone in your household been ill with GI symptoms during the last two weeks? Y N 1) If yes, who: _______________________________________ Onset date: ____ / ____ / ____ Time: ____:____ AM PM What were their symptoms(circle)? Nausea / Vomiting / Diarrhea / Abd. cramps / Fever / Headache / Other: ________________ 2) If yes, who: _______________________________________ Onset date: ____ / ____ / ____ Time: ____:____ AM PM What were their symptoms(circle)? Nausea / Vomiting / Diarrhea / Abd. cramps / Fever / Headache / Other: ________________ Do you know anyone else (friend, co-worker, etc.) who was ill with GI symptoms during this same time period? 1) If yes, who: _______________________________________ When/Onset: ____ / ____ / ____ 23 Y N What were their symptoms(circle)? Nausea / Vomiting / Diarrhea / Abd. cramps / Fever / Headache / Other: ________________ 2) If yes, who: _______________________________________ When/Onset: ____ / ____ / ____ What were their symptoms(circle)? Nausea / Vomiting / Diarrhea / Abd. cramps / Fever / Headache / Other: ________________ EXPOSURES Did you work at the Roehl Transport Event on Saturday, April 16th? Y If yes, did you eat any of the food items served at the Roehl Transport Event? Do you ever eat food items from Hotel Marshfield (during shifts or otherwise)? N Y Y N Do you ever bring food items home with you for other members of you household? Y N Which of the following items served at the Roehl Transport Event on April 16th did you eat/drink? details are requested. Please note any items consumed that are not on this list) Food Item Yes/No Details APPETIZERS (served 4- 6 p.m.) Layered taco dip Y N Unk Y N Unk Y N Unk Honeydew melon Y N Unk Cantaloupe Y N Unk Watermelon Y N Unk Grapes Y N Unk Other fruit Y N Unk Bruschetta Y N Unk Baked spinach & artichoke dip Y N Unk Y N Unk Y N Unk Y N Unk Ranch dressing Y N Unk French dressing Y N Unk Dinner rolls Y N Unk Butter Y N Unk Salmon with lemon dill cream sauce Y N Unk Steamed asparagus Y N Unk Diced garlic red potatoes Y N Unk Cherry maple pork loin w/ cherry sauce Y N Unk Mashed potatoes Y N Unk Gravy Y N Unk Green beans almandine Y N Unk New York strip steak w/ red wine sauce Y N Unk Garlic chive mashed potatoes Y N Unk Honey glazed carrots Y N Unk Pasta primavera Y N Unk Tortilla chips Fruit platter Chips for artichoke dip Other appetizer Specify: Specify: DINNER ITEMS House salad 24 N (please ask each item individually and note when additional Other entrée or side dish: Y N Unk Y N Unk Black Forest chocolate Y N Unk Carrot cake Y N Unk Strawberry cheesecake (white) Y N Unk Y N Unk Specify: DESSERT Cupcakes Cookies (for overnight guests) Caramel apple Y N Unk Chocolate Toffee Teasers Y N Unk Chocolate explosion Y N Unk Peanut butter melts Y N Unk Y N Unk Y N Unk Water from carafe on table Y N Unk Bottled water Other dessert item Specify: BEVERAGES (throughout the night) Water Y N Unk Soda/soft drinks/pop Y N Unk Hot tea Y N Unk Coffee Y N Unk Y N Unk Milk Y N Unk Beer Y N Unk Specify: Wine Y N Unk Specify: Mixed drink(s) Y N Unk Specify: Other beverage(s) Y N Unk Specify: Was there ice in any of your drinks? Y N Unk Cream/Milk in coffee or tea Specify: LATE NIGHT APPETIZERS/SNACKS served at 8:30 p.m. Cheese/sausage/cracker platter Y N Unk Cheese Y N Unk Sausage Y N Unk Crackers Y N Unk Other platter item Y N Unk Y N Unk Carrots Y N Unk Broccoli Y N Unk Cauliflower Y N Unk Tomatoes Y N Unk Celery Y N Unk Other vegetable Y N Unk Dill dip Y N Unk Chicken wings Y N Unk Swedish meatballs Y N Unk Stuffed mushroom caps with sausage stuffing Y N Unk Vegetable platter Specify: Specify: What flavor sauce(s)? 25 Cupcakes (leftover) Y N Unk Black Forest chocolate Y N Unk Carrot cake Y N Unk Strawberry cheesecake (white) Y N Unk Y N Unk Other appetizer/snack Specify: Additional Comments: THANK YOU FOR YOUR TIME! 26