HEPATITIS B

Communicable Disease: Hepatitis B

Word Count: 3565Communicable Disease: Hepatitis B

Introduction

Injury to liver cells caused by hepatitis B virus (HBV), a double-stranded DNA virus. It may appear as an asymptomatic, acute, chronic, or fulminant infection. Acute infection often marked by jaundice nausea and vomiting joint pains, rashes, and marked elevations in serum liver function tests. Chronic infection typically is asymptomatic and may be detected only by blood tests until it causes late complications (example, cirrhosis, portal hypertension, or hepatocellular carcinoma). Fulminant hepatitis B infection occurs when the patient suffers hepatic encephalopathy within 8 weeks of the onset of the disease (Kerkar, 2005, pp.685-691).Identity and present relevant epidemiology of the disease

The virus is transmitted by exposure to blood or body fluids of an infected person. The incubation period is approximately 2 to 6 months. Acute infection usually resolves in less than 6 months.  Hepatitis B virus surface antigen does not clear from the blood within 6 months chronic hepatitis said to have developed. Each year in the U.S., about 300,000 people are infected with hepatitis B virus. Worldwide, chronic hepatitis affects about 300 million people.

Those at greatest risk for infection include intravenous drug abusers, people with multiple sex partners, men who have sex with men, infants born of HBV-infected mothers, and health care workers. Blood banks now routinely screen for HBV antigens, which has significantly reduced the transmission of infection by transfusion. People who have not been vaccinated against HBV; and receive a needle stick or have mucous membrane contact with blood or other body secretions should contact their occupational health department. Hepatitis B virus immune globulin (HBIg) can be given to provide temporary protection (Coffin & Roberts, 2011, pp.47-49).

Antigens and Antibodies

The primary antigenic markers used to diagnose hepatitis B infection include the following:

Hepatitis B surface antigen (HBsAg), the first marker to appear in the blood. It is sometimes detected before serum levels of hepatic enzymes rise.

Hepatitis B antigen (HBeAg) and hepatitis B DNA, markers of active viral replication and high infectivity.

Hepatitis B core antibodies (antibodies against the core antigen of hepatitis B), which indicate infection of a patient with hepatitis B virus. IgM antibodies against the core antigen (IgM anti-HBc) are present early in the course of infection and may sometimes be the only detectable evidence of an acute infection. IgG antibodies against the core antigen (anti-HBc) are present in any patient infected with the virus, either acutely or at some time in the past.

Protective IgG antibodies to the HB surface antigen (HBsAB), which develop late in the disease, persist for life and protect against reinfection. As hepatitis B surface antibody levels rise, HBsAg levels fall, indicating resolution of acute infection. Antibodies against hepatitis B core antigen and hepatitis are antigen is not protective. Approx. 5% to 10% of patients develop chronic infection (Glebe & Urban, 2007, pp.22-38).

Prevention

Hepatitis B vaccine, which contains the HB surface antigen, provides active immunity and is recommended for persons at increased risk (example, children, health care workers, hemodialysis patients, intravenous drug abusers). All pregnant women should be screened for ...