ABOUT HEPATITIS A B C

About Hepatitis

The word hepatitis simply means an inflammation of the liver without pinpointing a specific cause. Someone with hepatitis may:

• have one of several disorders, including a viral or bacterial infection of the liver
• have a liver injury caused by a toxin (poison)
• have liver damage caused by interruption of the organ's normal blood supply
• be experiencing an attack by his or her own immune system through an autoimmune disorder
• have experienced abdominal trauma in the area of the liver

Hepatitis is most commonly caused by one of three viruses:

1. the hepatitis A virus
2. the hepatitis B virus
3. the hepatitis C virus

In some rare cases, the Epstein Barr virus (which causes mononucleosis) also can result in hepatitis because it can cause liver inflammation. Other viruses and bacteria can cause hepatitis, including hepatitis D and E, chickenpox, and cytomegalovirus (CMV).

Hepatitis A

Hepatitis A (also called infectious hepatitis) is a common form of hepatitis in children. It's caused by the hepatitis A virus (HAV), which is present in the stool (feces or poop) of infected people. Infected stool might be found in small amounts in food and on objects (such as doorknobs and diapers). Hepatitis A can remain in the stool for several months after the initial illness, especially in younger babies and children.
HAV is spread:

• when someone ingests anything contaminated with HAV-infected stool (making it easy for the virus to spread in overcrowded, unsanitary living conditions)
• in water, milk, and foods (especially shellfish)

Because hepatitis A can be a mild infection, particularly in children, some people might not know that they've had it. HAV can cause prolonged illness for up to 6 months, but usually only causes short-lived, mild illness. It does not cause chronic liver disease. In milder cases, symptoms may be similar to a stomach virus (with vomiting and diarrhea).

Hepatitis B

Hepatitis B (also called serum hepatitis) is caused by the hepatitis B virus (HBV). HBV can cause a wide range of symptoms, from a mild illness and general feeling of being unwell to more serious chronic liver disease that can lead to liver cancer.
HBV spreads through:

• infected body fluids, such as blood, saliva, semen, vaginal fluids, tears, and urine
• a contaminated blood transfusion (this is uncommon in the United States)
• shared contaminated needles or syringes for injecting drugs
• sexual activity with an HBV-infected person
• transmission from HBV-infected mothers to their newborn babies

Hepatitis C

The hepatitis C virus (HCV) is spread by direct contact with an infected person's blood. Symptoms can be very similar to those of hepatitis A and B. However, infection with HCV can lead to chronic liver disease and is a leading reason for liver transplantation in the United States. Chronic HCV infection is also associated with liver cancer.
HCV is more common in adults than in children. In kids, it's often acquired through transmission from a mother to her newborn. It also can be spread by:

• sharing drug needles and intranasal drug use (snorting drugs)
• getting a tattoo or body piercing with unsterilized tools
• blood transfusions or organ transplants (especially before 1992; since then the U.S. blood supply and donated organs have been routinely screened for hepatitis C)
• sexual contact (although this is less common)
• hemodialysis (especially before 1990)

Rarely, people living with an infected person can contract HCV by sharing items that might contain that person's blood, such as razors, toothbrushes, or scissors.

Diagnosis

All of these viral hepatitis conditions can be diagnosed through blood tests.
Liver function tests might be used to determine how well the liver is working or if it is damaged. Sometimes, a liver biopsy (the removal of a small liver tissue sample for examination) is done to further check for organ damage. A liver biopsy also can help doctors choose the best treatment.
Ultrasounds or CAT scans can check for any progression to cancer, particularly in chronic HBV and HCV infection.

 taken from : http://kidshealth.org/parent/infections/bacterial_viral/hepatitis.html#a_Hepatitis_C