Infecting over a quarter of a billion people around the world, HBV is not known simply for its popularity. As a leading cause of cirrhois and liver cancer (hepatocellular carcinoma), HBV is also the first example of a successful recombinant vaccine for human infectious disease, making future preventative tactics for diseases such as HIV more of a reality.

   In Africa and Asia, nearly a quarter of the population are carriers of HBV with 2-10% being chronically infected. Patients with chronic infection generally remain asymptomatic for years until liver cirrhosis (degeneration of the liver) or hepatocellular carcinoma (liver cancer) develop. The rest of the cases are acute HBV infections, with 20-35% experiencing abnormal liver function and jaundice (yellowish skin due to liver cell death). A long incubation period of 30-180 days allows the virus to replicate.

   Men are almost twice as likely to develop chronic hepatits B as women; whereas the vast majority of neonatal exposures develops into chronic infection, showing HBV to be endemic. 






Genome: partial ds DNA, circular, monopartite, smallest at 3.2kb in length
Morphology: roughly spherical, icosahedral nucleocapsid.
Replication: Violates Central Dogma-DNA->RNA->DNA
Clinical Symptoms: Jaundice, fatigue, abdominal pain, nausea
Incidence: 140,000-320,000 annual infections
Transmission: Blood-borne, sexual, perinatal
Incubation Period: 30-180 days
Prevention: Recombinant HBV surface antigen vaccine or HBV immunoglobulin post-exposure prophylaxis.
Related Viruses: Duck Hepatits B, Ground Squirrel Hepatitis Virus, Wooley Monkey Hepatitis Virus, Woodchuck Hepatitis Virus

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