Hepatitis B is caused by the hepatitis B virus (HBV), which is a small, circular DNA virus. It has a complex structure containing surface and core antigens. HBV is transmitted through bodily fluids, most commonly through sexual contact or sharing needles. The virus has an incubation period of 50-150 days. Those at highest risk include babies born to HBV-positive mothers, intravenous drug users, people with multiple sex partners, and healthcare workers exposed to blood. The clinical features include fever, jaundice, abdominal pain, and eventually recovery over 3-6 weeks for most patients.

1. Hepatitis B
SHAHID

2. • Caused by hepatitis B virus (HBV), belonging to the group of hepadna
viruses.
• It is small, circular, 3200 base- pair size, HBV DNA codes for four sets of viral
products and has a complex, multi particle structure.
• The hepatitis B virus is 42nm in diameter and composed of 27 nm nucleocapsid
core containing hepatitis B core antigen(HBcAG), surrounded by outer lipo
protein coat (also called envelope) containing the surface antigen (HBsAG)
• while another soluble antigen in the nucleocapsid is called hepatitisB e antigen
(HBeAg)].
• Nucleocapsid core also bas DNA polymerase enzyme.

3. • Virion also referred to as Dane particle (ds DNA)
• The corresponding antibodies are:
• Anti-HBs
• Anti-HBc
• Anti-HBe.
• HBsAg-positive serum containing HBeAg is more likely to be highly
infectious than HBeAg-negative or anti-HBe positive serum

5. Epidemiology
• Incubation period is about 90 days (50-150 days).
• Humans are the only source of infection
• Major route of transmission is parenteral but occasionally non-
parenteral
• Serum HBsAg is positive in 30% cases of Down's syndrome,
lepromatous leprosy, leukaemia, Hodgkin's disease, polyarteritis
nodosa, patients on chronic haemodialysis and needle using drug
addicts.

6. MODES OF TRANSMISSION
 Sexual - sex workers and homosexuals are particular at risk.
 Parenteral – IV drug users, 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.

7. HIGH-RISK GROUPS FOR HBV INFECTION
People from endemic regions
Babies of mothers with chronic HBV
Intravenous drug abusers
People with multiple sex partners
Hemodialysis patients
Health care personnel who have contact with blood

8. Clinical Features
• Prodromal symptoms usually last for a few days to 2 weeks before the
onset of jaundice
• characterised by fever, chills, headache, malaise and prominent GI
symptoms like anorexia ,Nausea, vomiting and diarrhoea follow.
• Patients with HB V infection have polyarthralgia and occasionally a
"serum sickness syndrome" with skin rashes and polyarthritis
• upper abdominal pain, sometimes severe (due to stretching of liver
capsule).
• Urine is dark with yellowish discolouration of sclera.

9. • With onset of clinical jaundice constitutional symptoms diminish.
• Liver becomes palpable and tender.
• Enlarged cervical lymph nodes and splenomegaly.
• As obstruction to biliary canaliculi increases (cholestatic phase),
jaundice deepens, stools become paler, urine becomes darker and
liver becomes more palpable.

10. • Recovery phase-gradually appetite improves and gastrointestinal
symptoms subside; jaundice decreases, stools and urine become
normal, and liver size decreases. Over a period of 3-6 weeks, majority
recover
• Complete clinical and biochemical recovery occurs in 3-4 months from
the onset in hepatitis B and C.

11. THANK YOU