Investigating awareness, fear and control associated with norovirus and other pathogens and pollutants using best-worst scaling.

Pollutants found in the water and air environment represent an ever-growing threat to human health. Contact with some air-, water- and foodborne pathogens (e.g. norovirus) results in gastrointestinal diseases and outbreaks. For future risk mitigation, we aimed to measure people's awareness of waterborne and foodborne norovirus relative to other environment-associated pollutants (e.g. pesticides, bioaerosols, antibiotic resistant bacteria) and well-known risks (e.g. diabetes, dementia, terrorist attack). We used an online survey, which included a best-worst scaling component to elicit personal levels of control and fear prompted by norovirus relative to 15 other risks. There was a negative correlation between levels of fear vs. control for all 16 measured risks. Perceived infection control levels were higher amongst women compared to men and correlated with age and the level of qualification in both groups. Participants who had sought advice regarding the symptoms caused by norovirus appeared to have more control over the risks. Norovirus is associated with high levels of fear, however, the levels of control over it is low compared to other foodborne illnesses, e.g. Salmonella. Addressing this deficit in the public's understanding of how to control exposure to the pathogen in an important health need.

Gaps in food safety professionals' knowledge about noroviruses.

Noroviruses (NoVs) are the most common etiologic agents of endemic and epidemic foodborne disease in the United States. Food safety professionals play an important role in protecting the public from foodborne illness. A survey of food safety professionals (n = 314) was conducted to characterize their knowledge of NoVs and to identify gaps in this knowledge. To recruit individuals, 25 professional organizations promoted the survey via their Web sites, newsletters, and/or e-mail distribution lists. The survey used true or false and open-ended questions to assess knowledge about NoVs, including attribution, transmission, and prevention and control strategies, including food handling practices. The online survey was available from mid-October 2012 to mid-January 2013. Of the 314 respondents, 66.2% correctly identified NoVs as one of the three most common causes of foodborne disease in the United States. Only 5.4% of respondents correctly identified the three most common settings for NoV infections, and 65.0% of respondents had the misperception that cruise ships are one of the three most common settings. Seventeen respondents (5.4%) answered all 20 true-or-false questions correctly, 33 respondents (10.5%) answered at least 19 of the 20 questions correctly, and 186 respondents (65.0%) answered at least 15 of the 20 questions correctly (i.e., a score of 75% or higher). The content domain in which respondents had the most incorrect answers was food handling practices. Thirty-eight percent of respondents incorrectly responded that it is safe for restaurant workers infected with NoVs to handle packaged food, food equipment, and utensils. About half of respondents did not know the recommended sanitizing solution for eliminating NoVs from a contaminated surface. The survey findings identified several important gaps in food safety professionals' knowledge of NoVs. The study results will inform the development of a Web-based educational module on NoVs to improve efforts to prevent the spread of NoVs in retail and institutional food establishments.

The stress (of an) epidemic.

We examined the consequences of being exposed to an outbreak of the Norwalk virus at a small university. Data from 422 undergraduates supported a model in which the experience of symptoms and perceptions of the university's response to the outbreak predicted fear of future contamination. In turn, fear predicted strain and enhanced hygiene practices. Results are consistent with a model of disease outbreak as a traumatic stressor, and implications for organizations dealing with disease outbreaks are discussed.

Passenger behaviors associated with norovirus infection on board a cruise ship--Alaska, May to June 2004.

BACKGROUND: During May 2004, the Vessel Sanitation Program (VSP) investigated an outbreak of norovirus gastroenteritis on board a cruise ship sailing in Alaska waters. The objectives were to identify a common food item source and explore behavioral risk factors for person-to-person transmission among passengers. METHODS: A case was defined as three or more episodes of loose stools within 24 hours or two or fewer episodes of loose stools accompanied by one or more episodes of vomiting. Vomitus and stool samples from affected passengers were tested for norovirus by reverse transcriptase-polymerase chain reaction. Environmental health officers performed an environmental investigation following VSP protocol. Questionnaires about food items consumed and behavioral risk factors were placed in cabin mailboxes (n = 2,018). A case-control study design using multivariable logistic regression tested associations between risk factors and disease. RESULTS: A total of 359 passengers (24.1% of respondents) met the case definition. Four of seven clinical specimens tested positive for norovirus. No significant deficiencies in environmental health practices were identified, and no meal servings were associated with disease. Having a cabin mate sick with diarrhea or vomiting [odds ratio (OR): 3.40; 95% confidence interval (CI) = 1.80-6.44] and using a specific women's toilet that was contaminated with vomit (OR: 5.13; 95% CI = 1.40-18.78) were associated with disease. Washing hands before meals was protective (OR: 0.25; 95% CI = 0.12-0.54) against disease. CONCLUSIONS: Widespread person-to-person norovirus outbreaks can occur on board cruise ships, even with appropriate environmental health practices. Programs to prevent and control norovirus outbreaks on board cruise ships should involve strategies that disrupt person-to-person spread and emphasize hand washing.