1. Dr. Mohd. Shaker An Overview
Hepatitis A-E Viruses
Dr. Mohd. Shaker
An Overview

2. Viral Hepatitis - Historical Perspectives
Enterically
transmitted
“Infectious” A E
Viral hepatitis
NANB
Parenterally
transmitted
“Serum” B D C
F, G, TTV
? other 2

3. Type of Hepatitis A B C D E Source of feces blood/ blood/ blood/ feces
virus
blood-derived
blood-derived
blood-derived
body fluids
body fluids
body fluids
Route of
fecal-oral
percutaneous
percutaneous
percutaneous
fecal-oral
transmission
permucosal
permucosal
permucosal
Chronic no
yes
yes
yes no
infection
Prevention
pre/post-
pre/post-
blood donor
pre/post-
ensure safe
exposure
exposure
screening;
exposure
drinking
immunization
immunization
risk behavior
immunization;
water
modification
risk behavior
modification 3

4. Hepatitis A Virus 6

5. Hepatitis A - Clinical Features
Incubation period: Average 30 days
Range days
Jaundice by <6 yrs, <10% age group: yrs, 40%-50% >14 yrs, 70%-80%
Complications: Fulminant hepatitis Cholestatic hepatitis Relapsing hepatitis
Chronic sequelae: None 7

6. Hepatitis A Infection Typical Serological Course Total anti-HAV Titre
Symptoms
Titre
ALT
Fecal
HAV
IgM anti-HAV 1 2 3 4 5 6 12 24
Months after exposure 9

7. Hepatitis A Virus Transmission
Close personal contact (e.g., household contact, sex contact, child day care centers)
Contaminated food, water (e.g., infected food handlers, raw shellfish)
Blood exposure (rare) (e.g., injecting drug use, transfusion) 11

8. Global Patterns of Hepatitis A Virus Transmission
Disease
Peak Age
Endemicity
Rate
of Infection
Transmission Patterns
High
Low to
Early
Person to person;
High
childhood
outbreaks uncommon
Moderate
High
Late
Person to person;
childhood/
food and waterborne
young adults
outbreaks
Low
Low
Young adults
Person to person;
food and waterborne
outbreaks
Very low
Very low
Adults
Travelers; outbreaks
uncommon 15

10. Laboratory Diagnosis
Acute infection is diagnosed by the detection of HAV-IgM in serum by EIA.
Past Infection i.e. immunity is determined by the detection of HAV-IgG by EIA.

11. Hepatitis A Vaccination Strategies
Epidemiologic Considerations
Many cases occur in community-wide outbreaks
no risk factor identified for most cases
highest attack rates in 5-14 year olds
children serve as reservoir of infection
Persons at increased risk of infection
travelers
homosexual men
injecting drug users 18

12. Hepatitis A Prevention - Immune Globulin
Pre-exposure
travelers to intermediate and high HAV-endemic regions
Post-exposure (within 14 days)
Routine
household and other intimate contacts
Selected situations
institutions (e.g., day care centers)
common source exposure (e.g., food prepared by infected food handler) 27

13. Hepatitis B Virus 28

14. Hepatitis B - Clinical Features
Incubation period: Average days
Range days
Clinical illness (jaundice): <5 yrs, <10% yrs, 30%-50%
Acute case-fatality rate: 0.5%-1%
Chronic infection: <5 yrs, 30%-90% yrs, 2%-10%
Premature mortality from chronic liver disease: 15%-25% 29

15. Spectrum of Chronic Hepatitis B Diseases
1. Chronic Persistent Hepatitis - asymptomatic
2. Chronic Active Hepatitis - symptomatic exacerbations of hepatitis
3. Cirrhosis of Liver
4. Hepatocellular Carcinoma

16. Acute Hepatitis B Virus Infection with Recovery
Typical Serologic Course
Symptoms
HBeAg
anti-HBe
Total anti-HBc
Titre
anti-HBs
HBsAg
IgM anti-HBc 4 8 12 16 20 24 28 32 36 52
100
Weeks after Exposure 30

17. Progression to Chronic Hepatitis B Virus Infection
Typical Serologic Course
Acute
(6 months)
Chronic
(Years)
HBeAg
anti-HBe
HBsAg
Total anti-HBc
Titre
IgM anti-HBc 4 8 12 16 20 24 28 32 36 52
Years
Weeks after Exposure 31

18. Outcome of Hepatitis B Virus Infection
by Age at Infection
100
100 80
Chronic Infection (%) 80 60 60
Chronic Infection
Symptomatic Infection (%) 40
Chronic Infection (%) 40 20 20
Symptomatic Infection
Birth
1-6 months
7-12 months
1-4 years
Older Children
and Adults
Age at Infection 34

19. Global Patterns of Chronic HBV Infection
High (>8%): 45% of global population
lifetime risk of infection >60%
early childhood infections common
Intermediate (2%-7%): 43% of global population
lifetime risk of infection 20%-60%
infections occur in all age groups
Low (<2%): 12% of global population
lifetime risk of infection <20%
most infections occur in adult risk groups 35

21. Concentration of Hepatitis B Virus in Various Body Fluids
Low/Not
High
Moderate
Detectable
blood
semen
urine
serum
vaginal fluid
feces
wound exudates
saliva
sweat
tears
breastmilk 1 1 1

22. Hepatitis B Virus Modes of Transmission
Sexual - sex workers and homosexuals are particular at risk.
Parenteral - IVDA, Health Workers are at increased risk.
Perinatal - Mothers who are HBeAg positive are much more likely to transmit to their offspring than those who are not. Perinatal transmission is the main means of transmission in high prevalence populations. 2 2 2

23. Diagnosis
A battery of serological tests are used for the diagnosis of acute and chronic hepatitis B infection.
HBsAg - used as a general marker of infection.
HBsAb - used to document recovery and/or immunity to HBV infection.
anti-HBc IgM - marker of acute infection.
anti-HBcIgG - past or chronic infection.
HBeAg - indicates active replication of virus and therefore infectiveness.
Anti-Hbe - virus no longer replicating. However, the patient can still be positive for HBsAg which is made by integrated HBV.
HBV-DNA - indicates active replication of virus, more accurate than HBeAg especially in cases of escape mutants. Used mainly for monitoring response to therapy.

24. Treatment
Interferon - for HBeAg +ve carriers with chronic active hepatitis. Response rate is 30 to 40%.
Lamivudine - a nucleoside analogue reverse transcriptase inhibitor. Well tolerated, most patients will respond favorably. However, tendency to relapse on cessation of treatment. Another problem is the rapid emergence of drug resistance.
Successful response to treatment will result in the disappearance of HBsAg, HBV-DNA, and seroconversion to HBeAg.

25. Prevention
Vaccination - highly effective recombinant vaccines are now available. Vaccine can be given to those who are at increased risk of HBV infection such as health care workers. It is also given routinely to neonates as universal vaccination in many countries.
Hepatitis B Immunoglobulin - HBIG may be used to protect persons who are exposed to hepatitis B. It is particular efficacious within 48 hours of the incident. It may also be given to neonates who are at increased risk of contracting hepatitis B i.e. whose mothers are HBsAg and HBeAg positive.
Other measures - screening of blood donors, blood and body fluid precautions.

26. Hepatitis C Virus capsid envelope protein protease/helicase
RNA-dependent
RNA polymerase
c22
33c
c-100 5’ 3’
core E1 E2
NS2
NS3
NS4
NS5
hypervariable
region 7 7 7

27. Hepatitis C - Clinical Features
Incubation period: Average 6-7 wks
Range 2-26 wks
Clinical illness (jaundice): % (20-30%)
Chronic hepatitis: 70%
Persistent infection: %
Immunity: No protective antibody
response identified 8 8 8

28. Chronic Hepatitis C Infection
The spectrum of chronic hepatitis C infection is essentially the same as chronic hepatitis B infection.
All the manifestations of chronic hepatitis B infection may be seen, albeit with a lower frequency i.e. chronic persistent hepatitis, chronic active hepatitis, cirrhosis, and hepatocellular carcinoma.

29. Hepatitis C Virus Infection
Typical Serologic Course
anti-HCV
Symptoms
Titre
ALT
Normal 1 2 3 4 5 6 1 2 3 4
Months
Years
Time after Exposure 10 10 10

30. Risk Factors Associated with Transmission of HCV
Transfusion or transplant from infected donor
Injecting drug use
Hemodialysis (yrs on treatment)
Accidental injuries with needles/sharps
Sexual/household exposure to anti-HCV-positive contact
Multiple sex partners
Birth to HCV-infected mother 11 11 11

31. 14 14 14

32. Laboratory Diagnosis
HCV antibody - generally used to diagnose hepatitis C infection. Not useful in the acute phase as it takes at least 4 weeks after infection before antibody appears.
HCV-RNA - various techniques are available e.g. PCR and branched DNA. May be used to diagnose HCV infection in the acute phase. However, its main use is in monitoring the response to antiviral therapy.
HCV-antigen - an EIA for HCV antigen is available. It is used in the same capacity as HCV-RNA tests but is much easier to carry out.

33. Treatment
Interferon - may be considered for patients with chronic active hepatitis. The response rate is around 50% but 50% of responders will relapse upon withdrawal of treatment.
Ribavirin - there is less experience with ribavirin than interferon. However, recent studies suggest that a combination of interferon and ribavirin is more effective than interferon alone.

34. Prevention of Hepatitis C
Screening of blood, organ, tissue donors
High-risk behavior modification
Blood and body fluid precautions 15 15 15

35. Hepatitis D (Delta) Virus
 antigen
HBsAg
RNA 19 19 19

36. Hepatitis D - Clinical Features
Coinfection
severe acute disease.
low risk of chronic infection.
Superinfection
usually develop chronic HDV infection.
high risk of severe chronic liver disease.
may present as an acute hepatitis. 20 20 20

37. Hepatitis D Virus Modes of Transmission
Percutanous exposures
injecting drug use
Permucosal exposures
sex contact 21 21 21

38. HBV - HDV Coinfection Typical Serologic Course Titre
Symptoms
ALT Elevated
Titre
anti-HBs
IgM anti-HDV
HDV RNA
HBsAg
Total anti-HDV
Time after Exposure 22 22 22

39. HBV - HDV Coinfection Typical Serologic Course Titre
Symptoms
ALT Elevated
Titre
anti-HBs
IgM anti-HDV
HDV RNA
HBsAg
Total anti-HDV
Time after Exposure 22 22 22

40. HBV - HDV Superinfection
Typical Serologic Course
Jaundice
Symptoms
Total anti-HDV
ALT
Titre
HDV RNA
HBsAg
IgM anti-HDV
Time after Exposure 23 23 23

42. Hepatitis D - Prevention
HBV-HDV Coinfection
Pre or postexposure prophylaxis to prevent HBV infection.
HBV-HDV Superinfection
Education to reduce risk behaviors among persons with chronic HBV infection. 25 25 25

43. Hepatitis E Virus 26 26 26

44. Hepatitis E - Clinical Features
Incubation period: Average 40 days
Range days
Case-fatality rate: Overall, 1%-3% Pregnant women, %-25%
Illness severity: Increased with age
Chronic sequelae: None identified 27 27 27

45. Hepatitis E Virus Infection
Typical Serologic Course
Symptoms
ALT
IgG anti-HEV
Titer
IgM anti-HEV
Virus in stool 1 2 3 4 5 6 7 8 9 10 11 12 13
Weeks after Exposure 28 28 28

46. Epidemiologic Features
Hepatitis E -
Epidemiologic Features
Most outbreaks associated with faecally contaminated drinking water.
Several other large epidemics have occurred since in the Indian subcontinent and the USSR, China, Africa and Mexico.
In the United States and other nonendemic areas, where outbreaks of hepatitis E have not been documented to occur, a low prevalence of anti-HEV (<2%) has been found in healthy populations. The source of infection for these persons is unknown.
Minimal person-to-person transmission. 29 29 29

48. Prevention and Control Measures for Travelers to HEV-Endemic Regions
Avoid drinking water (and beverages with ice) of unknown purity, uncooked shellfish, and uncooked fruit/vegetables not peeled or prepared by traveler.
IG prepared from donors in Western countries does not prevent infection.
Unknown efficacy of IG prepared from donors in endemic areas.
Vaccine? 31 31 31