viral hepatitis caused by hepatitis A and E

1. Viral Hepatitis – A and E

2. Viral Hepatitis
• Hepatitis – inflammation of the liver due to any cause
• Viral hepatitis – term used for hepatitis caused by hepatotrophic
viruses
• These include HAV, HBV, HCV, HDV and HEV
• HAV and HEV are primarily transmitted by feco-oral route
• HBV, HCV and HDV are transmitted by the parenteral route

3. Hepatitis A
• Commonest cause of viral hepatitis worldwide
• Endemicity closely related to sanitary and living conditions
• Globally, an estimated 1.5 million cases occur annually
• Known to have potential to cause large outbreaks
• India is hyperendemic for HAV with very high infection rates in first
few years of life
• Most people develop immunity by 10 years of age

4. Epidemiology
Agent:
• HAV is a non-enveloped, single stranded RNA virus belonging to
Picornavirus family
• Relatively resistant to destruction

5. Epidemiology
Host:
• Common in children
• Usually asymptomatic in children below 6 years of age, with only 10%
developing jaundice
• Usually causes clinical disease in older children and adults with
jaundice occurring in 70% of cases

6. Epidemiology
Mode of Transmission:
• Predominantly by feco-oral route
• Others – blood borne transmission, sexual transmission and certical
transmission
• Secondary Attack Rate – 30%
Incubation period: About 4 weeks (15 – 50 days)
Period of Infectivity: 2 weeks before to 1 week after onset of jaundice

7. Clinical features
• Clinical course is indistinguishable from other types of acute viral hepatitis
• Typically include
• Fever, malaise, anorexia, nausea
• Jaundice
• Abdominal discomfort
• Dark urine
• Severity and mortality increases in older age groups
• Convalescence is slow with fatigue, nausea and lack of appetite
• No chronic infection
• Complications: Relapsing hepatitis, cholestatic hepatitis and fulminant
hepatitis

8. Diagnosis
• Clinically indistinguishable from other forms of hepatitis
• Diagnosis requires serologic detection of IgM antibodies
• IgM detectable from 5 days prior to onset of symptoms and
disappears within 6 months after infection
• IgG anti-HAV used to detect previous infection as it persists lifelong
• PCR used to detect virus in faeces, blood
• Other parameters – elevated serum bilirubin and liver enzymes

9. Treatment
• Symptomatic management
• Complete bed rest
• Low protein diet
• No specific anti-viral therapy

10. Prevention and control
• Good personal hygiene
• High quality standards for public water supplies
• Proper disposal of sanitary waste
• Water supply should be safeguarded against faecal contamination
Active Immunization:
• Inactivated Hepatitis A vaccine
• 2 doses, 6 – 18 months apart for above 1 year of age
• Immune response in almost 100% of adult recipients
• Large scale immunization not recommended in high endemic countries

11. Hepatitis E
• First identified in 1955 in India
• Recognized as distinct human disease in 1990s
• Endemic in many regions esp. in regions where HAV infection is highly
endemic
• In India, HEV is responsible for the majority of epidemic and sporadic
hepatitis in adults

12. Epidemiology
Agent:
• HEV is a non-enveloped, single stranded RNA virus
Host:
• Humans are end or inadvertent target due to its zoonotic origin
• High attack rate among young adults
• Pregnant women more frequently affected during outbreaks
• Disease is more severe with high mortality in pregnant women esp. 3rd
trimester

13. Epidemiology
Modes of transmission:
• Feco-oral route – contaminated food and water implicated in major
outbreaks
• Ingestion of uncooked shellfish responsible for sporadic cases in endemic
areas
• Vertical transmission seen with significant perinatal morbidity and mortality
• No evidence of parenteral or sexual transmission
Incubation period: About 40 days (3 – 8 weeks)
Period of communicability: Unknown

14. Clinical features
• Clinical signs and symptoms indistinguishable from HAV
• Jaundice, dark urine, anorexia, abdominal discomfort, nausea,
vomiting, tender hepatomegaly
• Mostly self limited disease except in pregnant women
• Infants infected by vertical transmission have increased risk of
fulminant hepatitis

15. Diagnosis and Treatment
• Detection of specific anti-HEV antibodies
• Detection of HEV in feces and serum by RT-PCR
• Infection is self limited
• Symptomatic treatment
• Hospitalization needed in pregnant women and those with fulminant
hepatitis

16. Summary