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The Dangers of Hepatitis:
What you should know from A to E

A young man with his arms folded

Most people have heard of hepatitis, but few understand the harm posed by this potentially deadly collection of diseases. Here's what you need to know.

The liver is the body's largest internal organ. It performs many important jobs, including changing food into energy and cleaning alcohol and poisons from the blood. The liver:

  • Makes bile, a yellowish-green liquid that helps with digestion
  • Produces proteins and blood-clotting factors that the body needs
  • Regulates glucose (sugar) in the blood and stores extra sugar
  • Works with the stomach and intestines to digest food
  • Stores vitamins and minerals
  • Removes toxic (poisonous) substances from the blood
illustration of the liver

The largest organ in your body, the liver is found behind the lower ribs on the right side of the abdomen. It changes food to energy and cleans alcohol and other poisons from your blood.

Hepatitis swells the liver, stopping it from working well. It can lead to scarring (cirrhosis) or cancer. Viruses cause most cases of hepatitis. The various types of the disease are named for the viruses which cause them. For example, the cause of hepatitis A is the hepatitis A virus. Drug or alcohol use can also lead to hepatitis. In other cases, your immune system attacks healthy liver cells in your body by mistake. Vaccines prevent some viral hepatitis forms. Sometimes hepatitis goes away by itself. If it does not, it can be treated with drugs. In some cases, hepatitis lasts a lifetime.

Hepatitis: Acute or Chronic?

Acute hepatitis is the initial infection, which may be mild or severe. If the infection lasts for six months or longer, the condition is called chronic hepatitis. Hepatitis A and E do not cause chronic hepatitis. Hepatitis viruses B, C, and D can produce both acute and chronic episodes of the illness. Chronic hepatitis B and C are especially serious.

Types of Hepatitis

Currently, five different viruses are known to cause viral hepatitis:

  • Hepatitis A: Sometimes called "infectious hepatitis," hepatitis A is spread by eating food or drinking water contaminated with human waste. Hepatitis A is rarely life-threatening.
  • Hepatitis B: Also called "serum hepatitis," hepatitis B spreads from mother to child at birth or soon after, and also through sexual contact, contaminated blood transfusions and needles. Hepatitis B may scar the liver (cirrhosis) and lead to liver cancer.
  • Hepatitis C: Formerly known as "non-A, non-B hepatitis," hepatitis C is the most common form of viral hepatitis. While it can be transmitted through contaminated blood transfusions and/or needles, for a substantial number of patients, the cause is unknown. It may scar the liver. Hepatitis C infection is common in about 25 percent of people who are HIV-positive. Hepatitis C also infects up to 90 percent of HIV-infected injection drug users. And it is more severe in patients with HIV.
  • Hepatitis D: This form most often infects intravenous (IV) drug users who are also carriers of the hepatitis B virus. It is spread only in the presence of the hepatitis B virus and is transmitted in the same ways. Hepatitis D is a serious health problem because it occurs in those with hepatitis B, increasing the severity of symptoms associated with hepatitis B.
  • Hepatitis E: Similar to hepatitis A, hepatitis E is prevalent in countries with poor sanitation. It is rare in North America and rarely life threatening.

Fast Facts

  • Hepatitis means inflammation of the liver. With hepatitis, the liver stops working well.
  • Viruses cause most hepatitis. Viral hepatitis is the most common cause of liver disease in the world.
  • At least five different viruses cause hepatitis in people. Hepatitis A and E are spread through contaminated food, water, and human waste. Hepatitis B, C, and D are spread through an infected person's blood or body fluids.
  • Vaccines protect against hepatitis A and B. No vaccines are available for hepatitis C, D, and E.
  • Hepatitis B, C, and D can cause long-lasting problems, including liver scarring (cirrhosis) and cancer.

To Find Out More

Read More "Hepatitis" Articles
The Dangers of Hepatitis / Hepatitis Can Strike Anyone / Hepatitis: Symptoms, Diagnosis, Treatment & Prevention

Spring 2009 Issue: Volume 4 Number 2 Pages 22 - 23