What type of virus is hepatitis B?
Hepatitis B is a type of viral hepatitis. It can cause an acute (short-term) or chronic (long-term) infection. People with an acute infection usually get better on their own without treatment. Some people with chronic hepatitis B will need treatment.
What type of cell does hepatitis B infect?
One of the reasons for chronic HBV infections is that the virus causes chronic, noncytocidal infections of hepatocytes, the principal cell type of the liver. Hepatocytes continuously shed virus into the bloodstream, ensuring that 100% of the hepatocyte population is infected.
Are all viruses lytic or lysogenic?
No matter the shape, all viruses consist of genetic material (DNA or RNA) and have an outer protein shell, known as a capsid. There are two processes used by viruses to replicate: the lytic cycle and lysogenic cycle. Some viruses reproduce using both methods, while others only use the lytic cycle.
What is the morphology of hepatitis B?
The infectious HBV virion (Dane particle) has a spherical, double-shelled structure 42 nm in diameter, consisting of a lipid envelope containing HBsAg that surrounds an inner nucleocapsid composed of hepatitis B core antigen (HBcAg) complexed with virally encoded polymerase and the viral DNA genome.
What is a hepatitis B carrier?
Hepatitis B carriers are people who have the hepatitis B virus in their blood, even though they don’t feel sick. Between 6% and 10% of those people who’ve been infected with the virus will become carriers and can infect others without knowing it.
Why does hep B have reverse transcriptase?
Retroviruses and Hepatitis B virus have a virally-encoded DNA polymerase (P) called reverse transcriptase for copying RNA to DNA. The viral membrane fuses with the cell membrane, releasing the core into the cytoplasm after the Hepatitis B virus has attached to the cell surface receptor, which is yet to be identified.
Is HBV lytic?
Notably, HBV does not directly kill the infected liver cell, as progeny virions are released in a non-lytic manner. Instead, much of its pathogenesis is related to immune responses of the host and to its genotoxic and oncogenic potential.
Can Lysogenic become lytic?
Lysogens can remain in the lysogenic cycle for many generations but can switch to the lytic cycle at any time via a process known as induction. During induction, prophage DNA is excised from the bacterial genome and is transcribed and translated to make coat proteins for the virus and regulate lytic growth.
Does hepatitis B use reverse transcriptase?
Hepatitis B viruses (hepadnaviruses) replicate their DNA genomes by reverse transcription of an RNA intermediate.
What is meant by HBsAg?
HBsAg (Hepatitis B surface antigen) – A “positive” or “reactive” HBsAg test result means that the person is infected with hepatitis B. This test can detect the actual presence of the hepatitis B virus (called the “surface antigen”) in your blood.