1 Foodborne & Waterborne Disease Viruses Suphachai Nuanualsuwan DVM, MPVM, PhD 3. Hepatitis viruses

2 Hepatitis-causing viruses Suphachai DVM, MPVM, PhD

3 Hepatitis-causing viruses Type Nucleic acidAlias Transmission HAV(+)ssRNAInfectious hepatitisFecal-oral HBVdsRNASerum hepatitisParental HCV(+)ssRNANon-A Non-BParental HDV(-)ssRNAHepatitis deltaParental HEV(+)ssRNANon-A Non-BFecal-oral Suphachai DVM, MPVM, PhD

4 Hepatitis A virus(HAV) 1. Virus particle hepatovirus, picornaviridae single serotype 28 nm (+)ssRNA Suphachai DVM, MPVM, PhD

5 Hepatitis A virus(HAV) 2. Implicated food shellfish water strawberry, lettuce Suphachai DVM, MPVM, PhD

6 Hepatitis A virus(HAV) 3. Disease pattern asymptomatic : kid < 5 yr. acute hepatitis : adult > 14 yr. mild gastrointestinal illness incubation period ~ 28 days(4 weeks) virus from GI -> liver -> immune response liver inflammation(hepatitis) -> jaundice -> liver enzyme(ALT) increase Suphachai DVM, MPVM, PhD

7 Hepatitis virus migrating to liver intestine

8 Hepatitis virus shedding to intestine Suphachai DVM, MPVM, PhD

9 Hepatitis A virus(HAV) 3. Disease pattern Suphachai DVM, MPVM, PhD

10 Hepatitis A virus(HAV) 3. Disease pattern HAV shedding in stool before onset of illness Immunoglobulin M rises as ALT enzyme rises IgM falls while IgG rises IgM represents recent infection IgG represents previous infection(permanent) HAV shedding ~ 2 weeks after onset of illness

11 Hepatitis A virus(HAV) 3. Disease pattern Suphachai DVM, MPVM, PhD

12 Hepatitis A virus(HAV) 4. Transmission/Control fecal-oral indirect transmission associated with sanitation food(shellfish) and water fomite secondary infection : household food handlers Suphachai DVM, MPVM, PhD

13 Discharge untreated sewage straight into the sea

14 Hepatitis A virus(HAV) 5. Epidemiology Worldwide epidemic

15 Hepatitis A virus(HAV) 5. Epidemiology > 90% got infected < 6 years children are carrier & asymptomatic Shanghai China outbreak associated with raw sewage contaminated shellfish in the coastal water -> 300,000 cases over months homosexual, drug users sanitation, institutional visit endemic area should get vaccinated

16 Estuarine Seashore Sewage dischargeBeach Suphachai DVM, MPVM, PhD

17 Hepatitis A virus(HAV) Foodborne and waterborne disease virus shellfish and sanitation children < 5 yr are carrier and asymptomatic incubation period ~ 48 days(long) virus shedding in stool before onset of illness Suphachai DVM, MPVM, PhD

18 Hepatitis E virus(HEV) 1. Virus particle enterically Non-A Non-B(ENANB) hepatitis virus enterically transmitted Non-A Non-B(ET-NANB) similar to Calicivirus diameter 32 nm (+)ssRNA 7,200 bases Suphachai DVM, MPVM, PhD

19 Hepatitis E virus(HEV) 2. Implicated food mostly drinking water Suphachai DVM, MPVM, PhD

20 Hepatitis E virus(HEV) 3. Disease pattern liver inflammation -> icterus, Hepatomegaly cannot distinguish from other viral Hepatitis GI illness: diarrhea, nausea, vomiting + headache, fever incubation period ~ 40 days (longer than that of HAV) illness duration ~ 4 weeks illness of middle aged adults (14-40 yr.) Suphachai DVM, MPVM, PhD

21 Hepatitis E virus(HEV) 3. Disease Pattern Week after exposure Virus in stool Clinical illness Titer ALT IgM anti-HEV IgG anti-HEV Suphachai DVM, MPVM, PhD

22 Hepatitis E virus(HEV) 3. Disease pattern HAV shedding in stool before onset of illness IgM rises as ALT rises IgG rises just soon after IgM IgM represents recent infection IgG represents previous infection last 2-14 yr. HAV shedding ~ 2 weeks after onset of illness

23 Hepatitis E virus(HEV) 4. Transmission/ Control Fecal-oral route water supplies sanitation Suphachai DVM, MPVM, PhD

24 Hepatitis E virus(HEV) 5. Epidemiology mortality rate % mortality rate up to 20% in pregnant swine HEV and human HEV are closely related endemic in southeast Asia(SEA), middle Asia, middle east, northern Africa, and Mexico Suphachai DVM, MPVM, PhD

25 Phylogenetic relationships between HEV isolates

26 Geographic distribution of Hepatitis E

27 Hepatitis E virus(HEV) fecal-oral route longer incubation period than that of HAV illness of adult with hepatomegaly serious in pregnant women temporary immunity Suphachai DVM, MPVM, PhD

28 Foodborne and Waterborne Disease Viruses Noroviruses is most prevalent Rotaviruses in kid & HAV, HEV in adult Fecal oral route Food: shellfish & Water: sanitation preventing virus transmission Preventing contamination Inactivation e.g. heat, chlorine, UV Suphachai DVM, MPVM, PhD

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