Hepatitis B transmission

Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease. It is caused by the hepatitis B virus (HBV) and can cause acute and chronic infection leading to severe complications, including cirrhosis (liver scarring) and liver cancer in 20–30% of patients.

Hepatitis B virus (HBV) is a deoxyribonucleic acid (DNA) virus belongs to family hepadnaviridae which includes two genera; orthohepadnavirus (infecting mammals) of which hepatitis B virus is the prototype, and avihepadnavirus (infecting birds) of which DHBV is the prototype.

HBV infection affects approximately two billion people worldwide at some point of their lives; among whom 350 million suffer from chronicity of this infection becoming a carrier of this virus.

HBV has been found in virtually all body secretions and excretions. HBV is transmitted primarily through:
• Birth to an infected mother. Between 80–90% of infants infected during the first year of life develop chronic infection.
• Sexual contact with an infected person
• Sharing contaminated needles, syringes, or other injection-drug equipment

• Hepatitis B can also be transmitted through medical and dental procedures, tattooing, piercing, sharing personal hygiene items, razors, and manicure and pedicure material contaminated with infected blood.

HBV is not spread through breastmilk, food or water or by casual contact such as hugging, kissing or sharing food or drinks with an infected person.

Hepatitis B infection acquired in adulthood leads to chronic hepatitis in less than 5% of cases, whereas infection in infancy and early childhood leads to chronic hepatitis in about 95% of cases.
Hepatitis B transmission

What may cause hepatitis B infection?

Hepatitis B is a serious health problem, and about one third of the world’s population have been exposed to or are currently infected with hepatitis B virus (HBV).

HBV is one of the most common DNA viruses that can cause aggressive hepatitis, cirrhosis and hepatocellular carcinoma. The virus specifically infects liver cells and can cause acute liver damage. 

Approximately 200,000 new HBV infections occur annually in the United States.

Hepatitis B is a blood borne disease. Most people infected with HBV became infected by exposure to infectious blood or bodily fluids. It has been detected in blood, sweat, tears, saliva, semen, vaginal secretions, menstrual blood, and breast milk.

The common ways of getting hepatitis B are by sharing needles and by having unprotected sex. 

Transmission can also occur by contact of mucous membrane with secretions or saliva containing HBV.

The HBV attaches itself it the membrane that surrounds a liver cell and injects its DNA core into the cell. The virus takes over the cell and causes it to reproduce the virus’s DNA instead of the cell’s DNA. When the liver cell is filled with copies of the virus, it bursts.
What may cause hepatitis B infection?