Hepatitis C What it is

Hepatitis C

The word "hepatitis" means inflammation of the liver. The usual cause of hepatitis is infection by a virus. At least six viruses, usually identified by the letters A through G, are known to cause hepatitis. In the United States, hepatitis A, hepatitis B, and hepatitis C are the most common types. Rarely, some kinds of hepatitis are not caused by infection. These non-contagious types of hepatitis can result from alcohol abuse, certain drugs, ingestion of toxic substances, or autoimmune disease (the body's own immune system attacks the liver).

Typically, hepatitis B and hepatitis C infections have distinct phases. The first, or acute phase, occurs soon after infection with the hepatitis virus and lasts for 6 months or less. Many individuals recover from acute hepatitis, and their livers return to normal within a few months. Depending on the type of hepatitis, however, some of the individuals who contract acute hepatitis infections may not be able to eliminate the virus. For these individuals, the acute infection may be followed by a chronic phase. Usually, chronic hepatitis involves a prolonged latent or inactive period. During this time, which may last 20 years or longer, individuals with hepatitis probably do not experience symptoms or feel ill. Generally, however, the virus continues to multiply, gradually causing liver damage. Typically, symptoms do not become apparent until liver damage is extensive. However, abnormal levels of liver enzymes such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST) may show if liver tests are done.

Hepatitis - Risk Factors and Symptoms

What are the risk factors?

Risk factors are circumstances or conditions that can increase the chances of developing a condition. Some of these behaviors can be changed and taking special precautions may be helpful for limiting others. Risk factors for hepatitis B include:

• Being tattooed or having body or ear piercing with contaminated instruments
• Immigration from areas where the disease is common, especially among children
• Injectable drug use
• Poor socioeconomic conditions
• Sexual activity with homosexual or bisexual men
• Sexual activity with more than one partner in 6 months
• Travel to high-risk countries in Africa, Asia, South America, and Eastern and Mediterranean parts of Europe

Other individuals who may be at greater risk are:

• Dialysis patients
• Health care workers
• Individuals who received a blood transfusion prior to July 1992
• Individuals with hemophilia, especially those who used blood-derived clotting factors before 1987
• Infants born to infected mothers
• Sexual or household contacts of infected individuals

What are the symptoms?

Many individuals who contract HBV are not even aware that they have hepatitis because the symptoms may be so mild. The most common symptoms of hepatitis B are often mistaken for the flu and they may not be recognized because they may not appear until one to 6 months after becoming infected. Some of these symptoms may be:

• Fatigue
• Loss of appetite
• Mild fever
• Muscle or joint aches

Additional symptoms that may appear a few days after the initial symptoms include:

• Bitter taste in the mouth or bad breath
• Clay-colored (light) stools
• Confusion
• Dark urine
• Nausea and vomiting
• Pain on the right side below the ribs
• Widespread itching
• Yellow colored skin or white areas of eyes (jaundice)

The following symptoms of more serious liver damage may occur months to years later in individuals with chronic hepatitis B:

• Bruising easily or the appearance of “spider veins” broken blood vessels that form a tangled, spiderlike appearance under the skin
• Changes in personality or behavior (encephalopathy)
• Pain on the upper left side of stomach (due to an enlarged spleen)
• Red coloration of the palms of the hands
• Swelling of the legs and stomach (ascites)
• Vomiting bright red blood or dark, grainy "coffee ground" material (as a result of bleeding from enlarged blood vessels in the oesophagus and stomach)

Hepatitis B - Who gets it, What causes it?

Hepatitis B

What causes it?

HBV is transmitted from individual to individual through contact with infected bodily fluids, such as blood. Because chronic carriers of HBV are often unaware that they have the virus, they may transmit the disease to others unknowingly. Injecting illegal drugs with contaminated needles or having sex with an infected individual are common ways to become infected. Sharing and reusing diabetes blood testing supplies with any infected individual may also cause an individual to become infected. In addition, instruments such as those used for tattooing and body piercing can spread hepatitis if they are not properly sterilized between uses. A mother who is infected can transmit HBV to her baby during childbirth. However, it is not transmitted through breast-feeding.

Once HBV makes its way to the liver, it multiplies. Symptoms usually develop within one to 6 months. Exactly how liver cells are damaged or why some individuals acquire chronic infection or liver cancer is unknown.

Who has it?

Of all the serious transmittable diseases, hepatitis is the most common. Up to 100,000 new cases of hepatitis B are reported each year in the United States, and the Centers for Disease Control and Prevention (CDC) estimates that 1.25 million Americans are infected with chronic hepatitis B.

Hepatitis B affects individuals of both sexes and all ages, ethnic groups, and sexual orientations. About one-fifth of the world’s population will have hepatitis B at sometime in their lives. It is more common in males, with the highest occurrence between the ages of 20 and 49 years. Individuals with hemophilia may be slightly more at risk, if they use clotting factors that are made from human blood.

In the United States, the acute form of hepatitis has been declining due to the availability of an effective vaccine and the aggressive promotion of vaccination among children and teenagers. Changes in high-risk behavior may also contribute to the decrease. In 1990, approximately 21,000 Americans were believed to have acute hepatitis B. By 2002, that number had dropped to approximately 8,000.

Chronic hepatitis B affects an estimated 1.25 million Americans and about 400 million chronic carriers are believed to exist in the world population. As the number of acute cases goes down, the number of chronic carriers of hepatitis B is also expected to decline. However, increases in occurrence have been observed among the major risk groups: individuals with compromised immune systems, sexually active individuals, and injectable drug users.

Hepatitis C - Causes

What causes it?

Why HCV attacks liver cells is not well understood, but liver damage may be caused in at least three possible ways:

1. Direct cell damage. Viral cells are parasites that depend on normal cells to multiply. Once a virus enters a normal cell, the virus uses the cell’s DNA to make more virus, which is released when the normal cell dies. While other viruses are more likely to infect other body cells, HCV affects liver cells.
2. The development of immune complexes in the liver. Proteins that are formed by the body’s immune system to get rid of the virus, immune complexes may also cause damage to liver cells.
3. The action of T-cells. Specialized white blood cells that attack and kill substances identified by the body as invaders, T-cells may destroy liver cells instead of HCV because the virus is changing so quickly.

Hepatitis

Introduction

The word "hepatitis" means inflammation of the liver. Rarely, some kinds of hepatitis are not caused by infection. These non-contagious types of hepatitis can result from alcohol abuse, certain drugs, ingestion of toxic substances, or autoimmune disease (the body's own immune system attacks the liver). The usual cause of hepatitis, however, is infection by a virus. At least six viruses, usually identified by the letters A through G, are known to cause hepatitis. In the United States, hepatitis A, hepatitis B, and hepatitis C are the most common.

Typically, hepatitis B and hepatitis C infections have distinct phases. The first, or acute phase, occurs soon after infection with the hepatitis virus and lasts for 6 months or less. Many individuals recover from acute hepatitis, and their livers return to normal within a few months. Depending on the type of hepatitis, however, some of the individuals who contract acute hepatitis infections may not be able to eliminate the virus. For these individuals, the acute infection may be followed by a chronic phase. Usually, chronic hepatitis involves a prolonged latent or inactive period. During this time, which may last 20 years or longer, individuals with hepatitis probably do not experience symptoms or feel ill. Generally, however, the virus continues to multiply, gradually causing liver damage. Typically, symptoms do not become apparent until liver damage is extensive. However, abnormal levels of liver enzymes such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST) may show if liver tests are done.

What is it?

Hepatitis B is a specific type of hepatitis caused by the virus that has been designated as hepatitis B virus (abbreviated as HBV), which causes inflammation and damage to the liver. As the virus infects more liver cells, inflammation and destruction of liver cells can interfere with the functions of the liver.

Normal Liver Functions That May Be Affected by Liver Damage
Breakdown of harmful substances to keep them from building up in the bloodstream
Production of bile to help digest food
Production of cholesterol and protein
Regulation of blood clotting
Storage and release of energy in the form of sugar

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Most individuals are able to fight off (or clear) infection with HBV and they recover in 2 to 4 months. Ordinarily individuals only get hepatitis B once and after the HBV infection has been cleared, the individual has lifelong immunity . Up to 10% of adults, 50% of children under the age of 5, and 90% of infants who contract hepatitis B will not be able to eliminate the virus in 6 months. These individuals are considered to be chronic carriers of HBV.

It is estimated that chronic hepatitis B affects 1.25 million people in the United States and leads to 5,000 U.S. deaths per year. Chronic hepatitis puts individuals at a greater risk of developing cirrhosis or liver cancer. Cirrhosis is a condition that gradually replaces active liver cells with inactive scar tissue. Slowly, liver function is lost and liver failure may result. However, individuals who are chronic carriers of HBV but who have no symptoms are much less likely to develop cirrhosis than individuals who have chronic symptoms of hepatitis B.

Hepatitis C - Risk Factors - Who gets Hepatitis C?

Who has it?

The World Health Organization estimates that 180 million people around the world (about 3% of the population) are infected with HCV. Although it affects members of all ethnic groups, hepatitis C appears to be more common in less industrialized areas of the world, with estimates as high as 20% of the population in some countries.

According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), 4.1 million Americans (about 1.6% of the population) show evidence of having had an infection with HCV. Only about 25% of those individuals experienced symptoms that were attributed to hepatitis C, but 55% to 85% of them went on to the chronic phase. The Center for Disease Control estimates that there are 26,000 new infections each year, a decrease from the average of 240,000 per year in the 1980s. Most will develop chronic liver disease, which may progress to cirrhosis or liver cancer. In the 1970s and 1980s, a number of individuals got hepatitis C from donated blood that was contaminated with HCV, Today, the risk of transfusion-associated hepatitis C is very low (approximately one chance for every 100,000 units that are transfused). Approximately 25% of people who have HIV/AIDS will develop hepatitis C. Persons with HIV are more prone to get hepatitis C through sexual exposure.

What are the risk factors?

Mainly, HCV is passed from one individual to another through blood and blood products. A much smaller chance exists that it may also be transferred in bodily secretions, such as semen. The risk for infection with HCV is increased for individuals who:

• are born to mothers who have HCV
• had contact with high-risk individuals more than 6 months before the onset of symptoms
• have ever injected street drugs (even only once or many years ago)
• have HIV or AIDS
• have sexual contact with an infected individual
• live in poor socioeconomic conditions
• received transfusions of blood or blood products (especially before July 1992)
• require long-term kidney dialysis
• used blood-derived clotting factors before 1987
• work in health care facilities where they may be exposed to blood
• have liver disease

Illegal injection drug use accounts for about 60% of new HCV infections in the United States. In approximately 10% of infections, the source of exposure is unknown.

Hepatitis - Treatments

How is it treated?

Hepatitis B that lasts beyond 6 months or becomes serious may be treated with several different medications, but not every case needs to be treated. Whether or not an individual with hepatitis B is taking medication, regular visits to a doctor who specializes in liver diseases are very important. Laboratory tests that measure liver function, need to be performed regularly to track disease progression and to determine possible complications. Because no cure has been found for hepatitis B, treatment is aimed at decreasing the ability of the virus to multiply, decreasing inflammation and damage to the liver, and increasing the immune system’s ability to fight the virus.

Currently, drug treatments seem to be most helpful for individuals who have liver disease caused by hepatitis B. Unfortunately, there is no drug treatment for the acute phase of hepatitis B. Nausea and vomiting often seen with early infection is treated with fluid replacement. In the United States, the four drugs that have been approved by the Food and Drug Administration (FDA) for treating chronic hepatitis B are:

Interferon-alpha (Intron A and Pegasys) A synthetic version of antiviral proteins produced by the immune system, artificial interferon is used to treat a number of conditions. Although it may cause side effects such as depression, headache and flu-like symptoms, interferon is approved for both children and adults with hepatitis B. It is given by injection several times a week. There is also a modified form of interferon known as peginterferon that has been approved for the treatment of Hepatitis B and C. It has a similar but larger chemical structure than interferon-alpha that improves how the drug works and only needs to be injected once weekly.

Lamivudine (Epivir-HBV) Taken orally once a day for at least a year, lamivudine is approved for use by both children and adults with chronic hepatitis B. It has very few side effects, but long term use of lamivudine is likely to cause the hepatitis virus to become resistant to the effects of this medicine. Because of this, combination therapy and the use of other medicines to treat hepatitis B are areas of intense study.

Adefovir dipivoxil (Hepsera) Approved only for adults with chronic hepatitis B, adefovir is taken once a day as an oral tablet. Studies have shown that use of adefovir has been beneficial in reducing the amount of virus in the body without causing as much resistance as lamivudine. The most common side effects experienced by patients taking this medicine are headache, throat pain, and stomach pain.

Entecavir (Baraclude) Approved by the FDA March 30,2005, entecavir resembles a product needed by viral DNA to continue growing. It has been approved for chronic hepatitis B patients in whom the virus is active and replicating. Entecavir can also be used in patients with a resistant virus who have failed lamivudine therapy. Entecavir, taken as an oral tablet or solution once daily, is tolerated as well as lamivudine. The hepatitis B virus is much less likely to develop resistance to entecavir, representing a convenient treatment option for chronically infected patients.

Therapy with one drug is still considered to be the first line treatment approach and the choice of drug is specific to each patient with chronic hepatitis B. Combination therapy with interferon alpha and a nucleoside analog (like lamivudine or entecavir) may be used to prevent viral resistance and has shown promising results in reducing viral replication. However, further studies are needed to fully evaluate the benefit of combination therapy over treatment with one drug. Your doctor may run tests to check the health of your liver if you are on medicines like adefovir, lamivudine, or entecavir. If you are on any of these medicines, tell your doctor if you experience abdominal pain, skin discoloration, orange or dark urine, and frequent diarrhea or constipation.

Prevention of hepatitis B

Hepatitis B cannot be cured, but it can be prevented relatively easily.

Before exposure to HBV

The hepatitis B vaccine (Engerix-B, Recombivax HB) is a safe and effective protection from hepatitis B. Given as three injections during a 6-month period, it generally produces immunity for 15 years or longer. Generally, the injections are given in a doctor’s office or clinic.

Currently, hepatitis B vaccination is required by many school districts before a student is admitted. It is recommended for all individuals under the age of 19 years and for individuals who:

• are homosexual men
• have kidney dialysis
• have liver diseases (including other types of hepatitis)
• have multiple sex partners
• have or ever have had a sexually transmitted disease (for example, gonorrhea or syphilis)
• have sex with a partner who has hepatitis B
• have sex with multiple partners
• live in or travel to countries where hepatitis B is common
• live in the same home as an individual who has chronic hepatitis B
• may be exposed to HVB in blood

After exposure to the virus

Individuals who know or believe that they have been exposed to HBV, including babies born to mothers who test positive for HBV, should receive the three hepatitis B vaccine injections. They should also get one injection of hepatitis B immune globulin (BayHep B, Nabi-HB). Abbreviated as HBIG, this medication is made up of immune system proteins that specifically help to fight HBV.

Drug classes used to treat Hepatitis B

Interferons

Nucleoside Reverse Transcriptase Inhibitors