Hepatitis B

Table of Contents

Brief Introduction3

Give some background definitions.4

Structure4

Genome5

Replication6

Serotypes7

Hepatitis a general term7

Symptoms:10

Diagnosis:12

Treatment:14

Negative Health Effects:16

Causes:17

Risk Factors:19

Prevention:21

Epidemiology:25

Prevalence26

Transmission26

You could get hepatitis B from27

Conclusion:28

Hepatitis B

Brief Introduction

This paper mainly focuses on Hepatitis B - and provides information on this disease. Hepatitis B is a liver disease. Hepatitis means inflammation of the liver. Inflammation is the painful? red swelling those results when tissues of the body become injured or infected. Inflammation can cause organs to not work properly. Paragraph settings given in the body of the paper are defined as follows. Initially the paper introduces its purpose in this part and the disease that is focus of the paper. Second section presents background of the study then symptoms? diagnosis? Diagnosis? Treatment? Negative Health Effects? Causes? Risk Factors? Prevention? Epidemiology and finally we conclude the paper. The earliest record of an epidemic caused by Hepatitis B virus was made by Lurman in 1885. An outbreak of smallpox occurred in Bremen in 1883 and 1?289 shipyard employees were vaccinated with lymph from other people. After several weeks? and up to eight months later? 191 of the vaccinated workers became ill with jaundice and were diagnosed as suffering from serum hepatitis. Other employees who had been inoculated with different batches of lymph remained healthy. Lurman's paper? now regarded as a classical example of an epidemiological study? proved that contaminated lymph was the source of the outbreak. Later? numerous similar outbreaks were reported following the introduction? in 1909? of hypodermic needles that were used? and more importantly reused? for administering Salvarsan for the treatment of syphilis. The virus was not discovered until 1965 when Baruch Blumberg? then working at the National Institutes of Health (NIH)? discovered the Australia antigen (later known to be Hepatitis B surface antigen? or HBsAg) in the blood of Australian aboriginal people. Although a virus had been suspected since the research published by MacCallum in 1947? D.S. Dane and others discovered the virus particle in 1970 by electron microscopy. By the early 1980s the genome of the virus had been sequenced? and the first vaccines were being tested.

Give some background definitions.

Structure

Hepatitis B virus (HBV) is a member of the Hepadnavirus family. The virus particle? (virion) consists of an outer lipid envelope and an icosahedra nucleocapsid core composed of protein. The nucleocapsid encloses the viral DNA and a DNA polymerase that has reverse transcriptase activity. The outer envelope contains embedded proteins which are involved in viral binding of? and entry into? susceptible cells. The virus is one of the smallest enveloped animal viruses with a virion diameter of 42nm? but pleomorphic forms exist? including filamentous and spherical bodies lacking a core. These particles are not infectious and are composed of the lipid and protein that forms part of the surface of the virion? which is called the surface antigen (HBsAg)? and is produced in excess during the life cycle of the virus.

Genome

The genome of HBV is made of circular DNA? but it is unusual because the DNA is not fully double-stranded. One end of the full length strand ...