• in water, milk, and foods, especially in shellfish

Because hepatitis A can be a mild infection, particularly in children, it's possible for some people to be unaware that they have had the illness. In fact, although medical tests show that about 40% of urban Americans have had hepatitis A, only about 5% recall being sick. Although the hepatitis A virus can cause prolonged illness up to 6 months, it typically only causes short-lived illnesses and it does not cause chronic liver disease.

Hepatitis B

Hepatitis B (also called serum hepatitis) is caused by the hepatitis B virus (HBV). HBV can cause a wide spectrum of symptoms ranging from general malaise to chronic liver disease that can lead to liver cancer.

The hepatitis B virus spreads through:

• infected body fluids, such as blood, saliva, semen, vaginal fluids, tears, and urine

• a contaminated blood transfusion (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. The symptoms of the hepatitis C virus can be very similar to those of the hepatitis A and B viruses. However, infection with the hepatitis C virus can lead to chronic liver disease and is the leading reason for liver transplant in the United States.

The hepatitis C virus can be spread by:

• sharing drug needles

• getting a tattoo or body piercing with unsterilized tools

• blood transfusions (especially ones that occurred before 1992; since then the U.S. blood supply has been routinely screened for the disease)

• transmission from mother to newborn

• sexual contact (although this is less common)

Hepatitis C is also a common threat in kidney dialysis centers. Rarely, people living with an infected person can contract the disease by sharing items that might contain that person's blood, such as razors or toothbrushes.

Hepatitis D

Hepatitis D is considered a subviral satellite, as it can only propagate in the presence of the Hepatitis B virus.

Hepatitis E

Hepatitis E produces symptoms similar to hepatitis A, although it can take a fulminant course in some patients, particularly pregnant women; it is more prevalent in the Indian subcontinent.

Hepatitis F

Hepatitis F is a hypothetical virus linked to hepatitis. Several hepatitis F candidates emerged in the 1990s; none of these reports have been substantiated.

Hepatitis G

Another type of hepatitis, hepatitis G, has been identified, and is probably spread by blood and sexual contact. There is, however, doubt about whether it causes hepatitis, or is just associated with hepatitis, as it does not appear to be primarily replicated in the liver.

Q3. What is Difference between Acute and Chronic Hepatitis?

Acute hepatitis is when it lasts less than 6 months and chronic hepatitis is when it persists longer.

Q4 . What are consequences of Chronic infection?

About 80% of newly infected patients progress to develop chronic infection. Cirrhosis develops in about 10% to 20% of persons with chronic infection, and liver cancer develops in 1% to 5% of persons with chronic infection over a period of 20 to 30 years. Most patients suffering from liver cancer who do not have hepatitis B virus infection have evidence of HCV infection. The mechanisms by which HCV infection leads to liver cancer are still unclear. Hepatitis C also exacerbates the severity of underlying liver disease when it coexists with other hepatic conditions. In particular, liver disease progresses more rapidly among persons with alcoholic liver disease and HCV infection.

Q5. What is Alcoholic Hepatitis?

Ethanol, mostly in alcoholic beverages, is a significant cause of hepatitis. Usually alcoholic hepatitis comes after a period of increased alcohol consumption. Alcoholic hepatitis is characterized by a variable constellation of symptoms, which may include feeling unwell, enlargement of the liver, development of fluid in the abdomen ascites, and modest elevation of liver blood tests. Alcoholic hepatitis can vary from mild with only liver test elevation to severe liver inflammation with development of jaundice, prolonged prothrombin time, and liver failure. Severe cases are characterized by either obtundation (dulled consciousness) or the combination of elevated bilirubin levels and prolonged prothrombin time; the mortality rate in both categories is 50% within 30 days of onset.

Q6. What are signs and symptoms of Hepatitis?

Hepatitis, in its early stages, may cause flu-like symptoms, including:

• malaise (a general ill feeling)

• fever 

• muscle aches

• loss of appetite

• nausea

• vomiting

• diarrhea

• jaundice (a yellowing of the skin and whites of the eyes)

But some people with hepatitis may have no symptoms at all and may not even know they're infected. Children with hepatitis A, for example, usually have mild symptoms or have no symptoms.

Q7. What is difference between Jaundice and Hepatitis?

Jaundice is not an illness, but a medical condition in which too much bilirubin – a compound produced by the breakdown of hemoglobin from red blood cells – is circulating in the blood. This excess of bilirubin causes the skin, eyes, and the mucus membranes (inside of the mouth) to turn a yellowish color. This yellowish color is due to the bilirubin dissolving in the fat layer just below the skin.

Hepatitis is inflammation of the liver, usually caused by bacterial or viral infection, drugs (including alcohol), toxins, or parasites.

Q8. What blood tests are available to check for Hepatitis?

Serology: viral antigens secreted in to the blood.    Antibody response.

Q9. What treatments are available for Hepatitis patients?

When symptoms are severe or laboratory tests show liver damage, it's sometimes necessary for hepatitis to be treated in the hospital. Here's a quick look at the treatments available for the various hepatitis viruses:

• There are no medications used to treat hepatitis A because it's a short-term infection that goes away on its own.

• Hepatitis B can sometimes be treated using medications. Four drugs are approved for use in adults with hepatitis B, but there hasn't been enough research yet on their use in children. However, you can talk to your child's doctor about a drug that may be available in some centers on a research basis for children.

• The treatment of hepatitis C has improved significantly with the use of two medications, only one of which is approved for use in children. Another more effective drug isn't approved for children yet but is available for kids in some centers on a research basis. In those adults who've just been infected with hepatitis C (by accidental needle injury, for example), combination therapy with the two drugs is the treatment of choice and can eliminate the virus in about 50% of the people infected.

Children with mild hepatitis may be treated at home. Except for using the bathroom, they should rest in bed until the fever and jaundice are gone and their appetite is normal. Kids with a lack of appetite should try smaller, more frequent meals and fluids that are high in calories (like milkshakes). They should also eat healthy foods rich in protein and carbohydrates and drink plenty of water.

Q10. Why is there no treatment for the acute Hepatitis A?

Hepatitis A is a viral disease, and as such, antibiotics are of no value in the treatment of the infection. Antiviral agents, as well as corticosteroids, have no effect in the management of the acute disease.

The administration of immune globulin (IG) may help preventing or improving the clinical manifestations of the disease if given within 2 weeks of infection, but it is of no help in the acute phase of hepatitis A. Therapy can only be supportive and aimed at maintaining comfort and adequate nutritional balance

Q11. Where is HAV a problem?

The Virus is present worldwide, and the risk of infection is inversely proportional to levels of sanitation and personal hygiene.

In developing countries with poor environmental hygienic conditions, nearly all children are infected with HAV before the age of 9. There is substantial underestimation of hepatitis A cases in these areas, because HAV infections for young children are mostly asymptomatic and therefore unrecognized.

As sanitation conditions improve, transmission shifts to older age groups and the incidence of symptomatic disease increases.

 Q12.  IS hepatitis Contagious?

Yes, Hepatitis A, hepatitis B, and hepatitis C are all contagious.                                                 

Q13.  How long can HCV live outside the body and transmit infection?

Recent studies suggest that HCV may survive on environmental surfaces at room temperature at least 16 hours, but no longer than 4days.