3. +
General Concepts …
VIRAL HEPATITIS :- is a serious disease caused by virus that
attacks the liver . There are various strains of viral hepatitis which can
cause lifelong infection, cirrhosis ( scarring) of the liver , liver cancer
, liver failure, and death.
six medically important viruses are commonly described as “hepatitis
viruses”:
HAV,HBV,HCV,HDV,HEV,HGV
4. +
Terms for Hepatitis ….
Acute: Short term and/or severe.
Chronic: Lingering or lasting - may or may not be severe
Fulminant: Developing quickly and lasting a short time, high
mortality rate.
Cirrhosis: Hardening: may be the result of infection or toxins (e.g.
alcohol)
Jaundice: Yellowing of the skin, eyes, etc due to raised levels of
bilirubin in the blood due to liver damage.
Hepatocellular carcinoma: is closely associated with hepatitis
B, and at least in some regions of the world with hepatitis C virus.
9. +
Modes of Transmission for HBV
Parenteral - IV drug abusers, health workers are
at increased risk.
Sexual - sex workers and homosexuals are
particular at risk.
Perinatal - (Vertical) - mother(HBeAg+)
→infant.
13. +
risk groups for HBV infection-High
People from endemic regions
Babies of mothers with chronic HBV
Intravenous drug abusers
People with multiple sex partners
Hemophiliacs and other patients requiting blood
and blood product treatments
Health care personnel who have contact with blood
14. +
Concentration of Hepatitis B Virus
in Various Body Fluids …
High Moderate
Low/Not
Detectable
blood semen urine
serum vaginal fluid feces
wound exudates saliva sweat
tears
breastmilk
15. +
…Pathogenesis & Immunity
Virus enters hepatocytes via blood
Immune response (cytotoxic T cell) to viral antigens expressed on
hepatocyte cell surface responsible for clinical syndrome
5 % become chronic carriers (HBsAg> 6 months)
Higher rate of hepatocellular ca in chronic carriers, especially those
who are “e” antigen positive
Hepatitis B surface antibody likely confers lifelong immunity (IgG
anti-HBs)
Hepatitis B e Ab indicates low transmissibility
17. +
Possible Outcomes of HBV Infection
Acute hepatitis B infection
Chronic HBV infection
3-5% of adult-
acquired infections
95% of infant-
acquired infections
Cirrhosis
Chronic hepatitis
12-25% in 5 years
Liver failureHepatocellular
carcinoma
Liver transplant
6-15% in 5 years 20-23% in 5 years
DeathDeath
20. +
Treatment …
Interferon alfa (Intron A) Response rate
is 30 to 40%.
Lamivudine (Epivir HBV)
(relapse ,drug resistance)
Adefovir dipivoxil (Hepsera)
21. +
Prevention …
Vaccination
- highly effective recombinant vaccines.
Hepatitis B Immunoglobulin (HBIG)
-exposed within 48 hours of the incident/
neonates whose mothers are HBsAg and HBeAg
positive.
Other measures
-screening of blood donors, blood and body fluid
precautions.
22. +
Hepatitis B Vaccine
Infants: several options that depend on status of the
mother
If mother HBsAg negative: birth, 0-2m,4-6m
If mother HBsAg positive: vaccine and Hep B immune
globulin within 12 hours of birth, 1-2m, <6m
Adults * 0,1, 6 months
Routine booster doses are NOT routinely recommended for any group
Vaccine recommended in
All those aged 0-18
Those at high risk
23. +
References
website
http://www.hepatitis-central.com/hbv/hepbfaq/viroligy.html
http://en.wikipedia.org/wiki/Hepatitis_B
http://www.who.int/mediacentre/factsheets/fs204/en/index.html
http://www.cdc.gov/vaccines/pubs/vis/downloads/vis-hep-b.pdf
http://www.worldhepatitisalliance.org/AboutViralHepatitis/Prevention_Diagnosis_Treatment.aspx
http://emedicine.medscape.com/article/177632-overview
Text books
Richard A, HARVEY, Pamela C,Champe, Bruce D, Fisher. Microbiology 2nd edition. Lippicott Williams &
wilkins. Chapter 26. PP(273-282)
Raphael Rubin, David S. Strayer. Rubin’s pathology 5th edition. Lippicott Williams & wilkins. Chapter 14.
PP(637-640)