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Causes and Risk Factors
Currently, there are at least five (5) forms of viral hepatitis:
Hepatitis A - (formerly called infectious hepatitis), is most common in children in developing countries, but is being seen more frequently in adults and in the western world. Hepatitis A is thought to be spread by a virus from an infected person's feces directly or indirectly contaminating food, raw shellfish, drinking water, cooking utensils or someone else's fingers. The incubation period is two to six weeks after infection. Hepatitis A is considered an acute condition.
Hepatitis B - (formerly called serum hepatitis), is the most serious form of hepatitis.
Hepatitis B is thought to be spread by a virus from sexual contact, blood transfusion or exposure to an infected person's blood via cuts, open sores, needle sharing, razor sharing or ear piercing tools. Additionally, hepatitis B can be spread from mother to child at birth. The incubation period is four to 25 weeks.
Ninety percent of all hepatitis B cases are considered acute, while the other 10 percent are considered chronic and may progress to cirrhosis (a disease of the liver caused by chronic damage to its cells), liver failure or liver cancer. Note: a person is at greater risk of contracting hepatitis B if they are sexually active, have unprotected sex, have more than one sexual partner, have a sexual transmitted disease (STD), share needles for injecting drugs, work in health care, or if they are a native of or spend large amounts of time in Alaska, the Pacific Islands, Africa, Asia or the Amazon region of South America.
Hepatitis C - (formerly called non-A, non-B hepatitis), is transmitted primarily by direct blood contact - via blood transfusion or and contaminated needles. Less common ways are through sexual contact or from mother to child at birth.
The incubation period is five to 10 weeks. Twenty-five percent of the hepatitis C cases are considered acute, while the other 75 percent are considered chronic, which may result in cirrhosis. Note: a person is at greater risk of contracting hepatitis C if they had a blood transfusion prior to 1991, experimented with IV drugs or intranasal cocaine, have been a long-term hemodialysis patient, work in health care, or have been exposed to unsterile equipment used for body piercing, tattooing, manicures/pedicures or acupuncture.
Hepatitis D - (formerly called delta hepatitis), is found mainly in intravenous drug users who are carriers of the hepatitis B virus. Hepatitis D can cause both acute and chronic disease.
Hepatitis E - (formerly called enteric or epidemic non-A, non-B hepatitis) resembles hepatitis A, but is caused by a different virus from hepatitis C and is commonly found in the Indian Ocean area. Hepatitis E is considered an acute condition.
There are two main types of nonviral hepatitis, called alcoholic hepatitis and toxic/drug-induced hepatitis, and two less common types of nonviral hepatitis, called autoimmune hepatitis and granulomatous hepatitis.
Alcoholic hepatitis - the most common precursor of cirrhosis in the U.S. While it may not develop in many patients until several decades of alcohol abuse, it appears in a few individuals within a year after onset of excessive drinking.
Toxic/drug-induced hepatitis - caused after inhalation or ingestion of a toxin, such as carbon tetrachloride, vinyl chloride, poisonous mushrooms or the use of certain medications. Several widely used drugs can produce an adverse liver reaction: Isoniazid (used for the treatment of tuberculosis), methyldopa (a treatment for high blood pressure), acetaminophen (pain reliever), antibiotics such as erythromycin, chlorpromazine, oral contraceptives and anabolic steroids.
Autoimmune hepatitis - a condition in which the liver is attacked by the body's immune system.
Granulomatous hepatitis - a condition in which abnormal collections of white blood cells collect in the liver.
Fortunately, most people recover completely from hepatitis A, E and nonviral hepatitis. Mild flare-ups may occur over a period of several months with viral hepatitis. Each flare-up is usually less severe than the initial attack, and a relapse does not necessarily indicate that complete recovery will not take place.
Unfortunately, hepatitis B, C and D can linger in the body, producing chronic, perhaps lifelong, infection. Additionally, carriers of the hepatitis virus can infect others, even though they feel perfectly well. They may face risks of liver disease (cirrhosis and liver cancer) in the future.
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