1. 1 Foodborne & Waterborne Disease Viruses Suphachai Nuanualsuwan DVM, MPVM, PhD 1. Introduction

2. 2 Foodborne and waterborne disease viruses Top 3 foodborne disease outbreak during 1988-1997(10 years) following bacteria and chemical Data from CDC most updated unknown etiology was ~ 64% passive record Suphachai DVM, MPVM, PhD

3. 3 Etiology % Outbreak Bacteria 28 Chemicals 5.6 Parasites 0.7 Viruses 1.9 Known etiology36.6 Unknown etiology63.7 Outbreak by etiology 1988-1997 Source : CDC 1996 Surveillance for foodborne disease outbreaks-US 1988-1992 MMWR 45(ss-5): 1-71 CDC 2000 Surveillance for foodborne disease outbreaks-US 1993-1997 MMWR 49(ss-1): 1-62

4. 4 Etiology % Cases Bacteria 13.47 Parasites 6.58 Viruses 79.95 Noroviruses59.54 Rotavirus10.10 Astrovirus10.10 Hepatitis A virus 0.22 Estimated cases by etiology Source : Mead, et al 1999. Food related illness and death in the United Stated Emerging Infectious diseases 5(5) 607-625

5. 5 Foodborne and waterborne viruses Estimated Top 1 of food-related illness Higher than bacteria & parasites combined Suphachai DVM, MPVM, PhD

6. 6 Common properties among FB-WB viruses inert transmissible particles fecal-oral route human specific non-cytopathic effect non-enveloped viruses Suphachai DVM, MPVM, PhD

7. 7 Common properties of FB-WB disease viruses 1. inert transmissible particles viruses are not a living organism diameter of < 30 nanometers (mostly) icosahedral symmetry single stranded RNA (+) (mostly) RNA-dependent RNA polymerase(RdRp) intracellular parasites Suphachai DVM, MPVM, PhD

8. 8 What is VIRUS ? A group of infectious agents characterized by their inability to reproduce outside of a living host cell. Viruses may subvert the host cells' normal functions, causing the cell to behave in a manner determined by the virus. Virion: Virus particle – Infectious (native) or noninfectious Suphachai DVM, MPVM, PhD

9. 9 Icosahedral symmetry Noroviruses Poliovirus type 1

10. 10 Nonenveloped enteric viruses in human DiameterNucleic acid (nm) Stranded RNA DNA 25-38singleAstrovirusParvovirus Calicivirus Coronavirus Picornavirus 70-85doubleReovirusAdenovirus Rotavirus

11. 11 Diameter of Hepatitis A virus ~ 28 nmDiameter of Calicivirus ~ 30 nm diameter of < 30 nanometers (mostly) Suphachai DVM, MPVM, PhD

12. 12 Common properties of FB-WB disease viruses 2. Fecal oral route transmission virus ingestion -> virus shedding direct transmission fecal-oral route person-to-person route indirect transmission food & water fomite Suphachai DVM, MPVM, PhD

13. 13 Common properties of FB-WB disease viruses 3. Human adaptation all FB-WB disease viruses are human specific except Hepatitis E virus(HEV) and Tick-borne encephalitis virus associated with sanitation rather than undercooked meat Suphachai DVM, MPVM, PhD

14. 14 Common properties of FB-WB disease viruses 4. Difficult to culture in laboratory human specific no lab host cells or no cytopathic effect(CPE) renders infectivity test difficult RT-PCR is a leading diagnostic tool yet cannot differentiate infectious and inactivated viruses Suphachai DVM, MPVM, PhD

15. 15 Common properties of FB-WB disease viruses 5. Non-enveloped viruses all FB-WB disease viruses are non-enveloped resistant to environmental condition e.g. pH, heating, UV Suphachai DVM, MPVM, PhD

16. 16 Foodborne and Waterborne Disease Viruses 1. Noroviruses(NV) formerly Norwalk-like viruses 2. Rotaviruses 3. Hepatitis A virus(HAV) 4. Hepatitis E virus(HEV) 5. Other viruses Astrovirus Parvovirus Tick-borne encephalitis virus Enteroviruses Adenovirus Coronavirus Suphachai DVM, MPVM, PhD

17. 17