Prevalence of Norovirus Among Citizens of the United States from 2006-2007

1. Prevalence of Norovirus Among Citizens of the United States from 2006-2007 Maria Ayzza Barcarse Michael Johnson Elman Punzalan Michael Rosete

2. Extent of the problem • Leading Cause of gastroenteritis & foodborne outbreaks in the United States • Accounts for 19-21 million reported cases of acute gastroenteritis each year • Very Contagious • No vaccination or antiviral medications available Centers for Disease Control and Prevention (CDC), 2013

3. Extent of the problem • Morbidity • 1.7-1.9 million annual outpatient visits • 400,000 annual emergency department visits • 56,000-71 annual hospitalizations • Mortality • 570-800 deaths, mostly in young children and elderly CDC, 2013

4. Agent of Disease • Non-enveloped, single-stranded RNA virus • Strains that infect humans - GI, GII, GIV • GII. 4 strain is responsible for causing majority of gastroenteritis outbreaks worldwide • Minerva Strain (GII. 4, 2006) strain was the viral strain involved in 2006-2007 US epidemic (CDC, 2007) CDC, 2007; CDC, 2013

5. The Norovirus Condition • Gastroenteritis: Inflammation of the stomach and intestinal tract • Commonly referred to as stomach flu or food poisoning CDC, 2013

6. The Norovirus Condition • Symptoms include: • Nausea • Aches (headaches, abdominal cramps) • Vomiting • Low-grade fever • Diarrhea • dehydration CDC, 2013

7. The Norovirus Condition • Symptoms appear 1-2 days after exposure • Full recovery between 1-3 days • Severe cases require hospitalization • Typically occurs in the elderly (+65 Y/O) • Diagnosis is made from symptoms of vomiting & diarrhea California Department of Public Health, 2013

8. Modes of Transmission • Direct contact • Fecal-oral route • Physical contact • Linen or clothing items soiled with feces or vomit • Contaminated services CDC, 2013

9. Modes of Transmission • Airborne droplet transmission • Vomiting CDC, 2013

10. Modes of Transmission • Indirect contact • Contaminated water • Food contamination • Improper handling of food (ex: shellfish) • Failure to wash hands California Department of Public Health, 2013; CDC, 2013

11. Mechanisms to control the problem or spread of disease • Routine hand washing • Proper food handling practices • wash & cook food thoroughly • Clean surfaces • Cleaning soiled laundry immediately CDC, 2013

12. Host Factors of Vulnerability • Due to the virulent nature, all people are affected • However, some may be at greater risk than others • Race • A single study of military personnel has suggested African Americans may have a protective factor.

13. Host Factors of Vulnerability • Gender, Marital Status • There is no evidence to suggest disparities based on gender or marital status, however married couples may have a higher risk for transmission due to close proximity. • Age • Young children and elderly are at higher risk for prolonged symptoms • These populations are at higher risk for dehydration and must quickly replenish water.

14. Environmental & Occupational Risks • Prevalent in Enclosed Areas • Including nursing homes, cruise ships, hospitals • Higher Risk for Those: • Working in food service, hotels or cruise ships • Working for institutional facilities such as schools, prisons, hospitals (Ecolab, 2013)

15. Geographic Risk • Tends to be more prevalent in colder climates and colder weather • Far north or south climates may be at greater risk Reynolds, et al, 2002; CDC, 2013

16. Geographic Risk • Geographic Study in Japan • Found over the course of three years that the Northern regions of Japan see a spike of norovirus cases as temperature and humidity rapidly drops in the Fall/Winter months. Suzuki, Saito, Matsuno, Shobugawa, 2013

17. Geographic Study in Japan Seino, n.d.

18. Temporal Variation • Cyclical Trends • Cases typically increase in the colder winter months of the year and decrease in warmer months

19. Temporal Variation • Norovirus is an Endemic • It is transmitted in all parts of the world and in the United States, occurs relatively frequently. • Epidemics • However, with major outbreaks such as 2006-2007’s outbreak, can become an Epidemic. • This is due to it’s tendency to spread rapidly and affect large amounts of people. (Media Office at the UNSW Australia, 2013)

20. Epidemiologic Variables • First identified in 1972 after a gastroenteritis outbreak occurred in Norwalk, Ohio. • Outbreaks have been traced back to companies who handle food. • Agricultural workers • Food suppliers/distributors • Restaurant workers California Department of Public Health, 2013

21. Hypotheses • Lack of adherence to food handling guidelines • Lack of proper sanitation and disinfection of contaminated surfaces • More time spent indoors during winter months

22. Norovirus 2006-2007 • When new strains of diseases are introduced, outbreaks often occur. • This occurred in the winter of 2006, continuing into 2007 with the “minerva” strain of Norovirus CDC, 2013

23. Norovirus 2006-2007 Norovirus Associated Deaths CDC, 2013

24. Norovirus 2006-2007 Norovirus Associated Hospitalizations CDC, 2013

25. Norovirus 2006-2007 Norovirus Associated Emergency Department Visits CDC, 2013

26. Norovirus 2006-2007 Norovirus Associated Outpatient Visits CDC, 2013

27. Gaps in knowledge • A researcher’s point of view, limited knowledge about the norovirus • Biological Data • Genetic Diversity CDC, 2013

28. Gaps in knowledge • The public's point of view, insufficient knowledge about the disease • A person can become infected with the norovirus multiple times throughout their lifetime. • Currently there is no treatment for it. CDC, 2013

29. Existing/Proposal Policies • Suspected Norovirus Outbreak • State, local, and territorial health departments • serve as the lead agencies • interview patients and perform diagnostic testing • Food regulatory agencies (FDA, USDA, and State authorities). • CDC investigations and control. • Kaplan Criteria CDC, 2013

30. Existing/Proposed Policies • Policies in a Healthcare Setting • Protocol • Notification of infected persons, including patients and staff members, to the proper authorities • Ward closures and isolation of infected persons from other patients • Aseptic technique with regards to hand washing and proper use of personal protective equipment when involved with a patient care. CDC, 2013

31. Significance of health policies • These health policies can help: • Prevention • Containment • Treatment

32. Areas for Further Epidemiologic Research • Identify emerging strains which are pathogenic. • Better understanding of the body’s response to various strains. • To determine the likelihood of a person to serve as a reservoir for transmission. • Identifying predisposing factors that increase susceptibility. • National Institute of Allergy and Infectious Diseases, 2013

33. Areas for Further Epidemiologic Research • Vaccine development • Identify individuals/groups most often infected to determine for whom the vaccine is of utmost priority. • High-risk groups: • Young children • Elderly • Special interest groups: • Healthcare workers • Travelers • Military personnel National Institute of Allergy and Infectious Diseases, 2013

34. Conclusion • Norovirus is very contagious! • Direct vs. Indirect transmission • Cleanliness and hand hygiene very helpful • Special concern for certain age groups • Not a quick fix • No available vaccine or antiviral medication • Caused by a virus

35. Class Activity

36. Question 1 Based upon our research, what factor does NOT contribute to the spread of norovirus. A. Climate and Weather B. Food Handling Practice C. Sedentary Lifestyles D. Disinfection of Surfaces

37. Question 2 Which Strain of Norovirus was prevalent in the 2006-2007 epidemic? A. The Bermuda Strain B. The Kreuzen-Johnson Strain C. The Minerva Strain D. The Yosemite-Islet Strain

38. Question 3 What groups of people are NOT considered to be at high risk for contracting norovirus. A. Elderly B. Institutional Workers C. Young Children D. College Students

39. Question 4 What is the significance of the geographic study in Japan? A. Helped to reinforce that colder climates have higher rates of norovirus B. Helped to establish that Asian races are at higher risk for contracting norovirus C. A & B D. None of the above

40. Bonus Question The Norovirus is the leading cause of gastroenteritis outbreaks in the United States. How many cases are reported each year?

41. References California Department of Public Health. (2013). Norovirus (Norwalk Virus). Retried October 5, 2013, from http://www.cdph.ca.gov/HealthInfo/discond/Pages/Norovirus.aspx Centers for Disease Control and Prevention (CDC). (2007). Norovirus activity - United States, 2006-2007. Retrieved from, http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5633a2.htm Centers for Disease Control and Prevention (CDC). (2013). Surveillance for Norovirus Outbreaks. Retrieved from, http://www.cdc.gov/features/dsnorovirus Centers for Disease Control and Prevention (CDC). (2013). Trends of Norovirus-associated outcome figures. Retrieved November 19, 2013, from http://www.cdc.gov/norovirus/trends-outbreaks-figure-1.html Ecolab Inc. (n.d.) Norovirus. Retrieved October 2, 2013, from http://www.ecolab.com/our-story/our-company/our-vision/safe-food/microbial-risks/norovirus Reynolds, R.W., N.A. Rayner, T.M. Smith, D.C. Stokes, and W. Wang (2002). "An improved in situ and satellite SST analysis for climate". J. Climate15: 1609-1625 Seino, H. (n.d.) Annual mean temperature graph. Retrieved November 17, 2013 from, from http://www.niaes.affrc.go.jp/topics/g7/tm.gif Suzuki, H., Saito, R., Matsuno, S., & Shobugawa, Y. (n.d.). The South to North Variation of Norovirus Epidemics from 2006–07 to 2008–09 in Japan. PLOS ONE : accelerating the publication of peer-reviewed science. Retrieved October 4, 2013, from http://www.plosone.org/articleinfo%3Adoi