What is Hepatitis?
Hepatitis: Inflammation of the liver from any cause.
Hepatitis is most often viral, due to infection with one of the hepatitis viruses (A, B, C, D, and E) or another virus (such as those that cause infectious mononucleosis, cytomegalovirus disease, or yellow fever). The main nonviral causes of hepatitis are alcohol and drugs.
Hepatitis is a major public health problem. Approximately 400 million people have hepatitis B and 170 million have hepatitis C. Both cause chronic liver infection that can be fatal. Hepatitis B and C are implicated in 80% of cases of liver cancer, the fourth leading cause of cancer deaths in the world.
All of these viruses cause acute, or short-term, viral hepatitis. The hepatitis B, C, and D viruses can also cause chronic hepatitis, in which the infection is prolonged, sometimes lifelong.
Other viruses may also cause hepatitis, but they have yet to be discovered and they are obviously rare causes of the disease.
TYPES OF Hepatitis :
Hepatitis A (which is often a milder form of this disease), is frequently transmitted by contaminated food, a route called fecal-oral contamination.
Hepatitis B more often involves transmission by exposure to blood or other body fluids. About 1 million people die worldwide as a result of hepatitis B, often either of liver failure or liver cancer.
Two other viruses are known, hepatitis D and E, but considered as “additional” complications for types B and C.
Other viruses, such as cytomegalovirus and Epstein-Barr virus, can also cause infectious hepatitis.
Hepatitis C infection can exist undetected for periods as long as 10 to 20 years, and researchers estimate that millions of people are infected and have not yet displayed any symptoms.
Causes of Hepatitis:
Some cases of viral hepatitis cannot be attributed to the hepatitis A, B, C, D, or E viruses. This is called non A…E hepatitis or hepatitis X. Scientists have identified several candidate viruses, but none have been proven to cause hepatitis. The search for the virus responsible for hepatitis X continues.
Hepatitis C is a disease of the liver caused by the hepatitis C virus (HCV). You may be at risk for hepatitis C if you:
were notified that you received blood from a donor who later tested positive for hepatitis C. have ever injected illegal drugs, even if you experimented a few times many years ago received a blood transfusion or solid organ transplant before July, 1992 were a recipient of clotting factor(s) made before 1987 have ever been on long-term kidney dialysis have evidence of liver disease (e.g., persistently abnormal ALT levels)
What Causes Hepatitis B?
What causes hepatitis B? There is only one cause of hepatitis B — an infection with the hepatitis B virus (also known as HBV). The hepatitis B virus is a DNA virus that belongs to the genus Orthohepadnavirus of the Hepadnaviridae family.
When a person is infected with the hepatitis B virus, the virus is able to enter liver cells from the blood and then use those cells to make more copies of the hepatitis B virus.