hepatitis..

Introduction
Hepatitis is a very significant global health concern. Several different viruses have been identified - (hepatitis A, B, C, D, and E viruses) - which, collectively, account for the majority of viral hepatitis in humans. Of these, hepatitis A and E viruses are transmitted through the fecal-oral route and cause only acute infections that are generally resolved without complications and impart long-term immunity. Hepatitis B, C and D, on the other hand, are transmitted through infected blood, frequently causing chronic infection, and are exceedingly dangerous, and often insidious, pathogens. They afflict more than half a billion people worldwide, and are responsible for over a million deaths a year. Chronic infection with these three viruses leads to cirrhosis of the liver, end stage liver disease, and primary liver cancer.
Viral hepatitis is a group of diseases of the liver that can be caused by consuming contaminated water or food, using dirty needles or syringes, or practicing unsafe sex.
Scientists have identified six hepatitis viruses, but three - known as A, B and C. People infected with hepatitis can experience effects ranging from mild illness to serious liver damage. Many recover completely from an infection, while others become carriers of the disease and can spread it to others unknowingly. It is especially important for women who are pregnant or are trying to become pregnant to get tested for hepatitis.



Types of Hepatitis
• Hepatitis A
• Hepatitis B
• Hepatitis C
• Hepatitis D
• Hepatitis E
• Hepatitis F
• Hepatitis G





Hepatitis A
The hepatitis A virus (also known as HAV) is transmitted when we eat or drink something that is contaminated. Raw or undercooked food, food handled by people who have not washed their hands, or water contaminated by animal or human waste are often sources of the virus.
Hepatitis A can be prevented by a variety of vaccines adapted to individual needs. Careful hand washing is one of the best preventive measures against hepatitis A.

Hepatitis B
Hepatitis B (HBV) is the most prevalent hepatitis strain in the world. People with acute HBV or who are carriers can spread the virus by sexual contact or through blood and other body fluids.
Many people infected with the hepatitis B virus recover completely and develop lifelong immunity to the virus. Unfortunately, about 90 per cent of babies born to mothers who are hepatitis B carriers have a high chance of developing chronic HBV in later life, which can lead to diseases such as cirrhosis and cancer of the liver.
Hepatitis B can be giving hepatitis B immune globulin to people who have had recent contact with infected body fluids (seven days or less) or immunization with a hepatitis B vaccine.

Hepatitis D
The Hepatitis D Virus (HDV) is a unique, defective RNA virus that can only infect an individual in the presence of hepatitis B. It occurs either as a co-infection with acute hepatitis B or as a super infection in people with chronic hepatitis B. Hepatitis D is mostly found among IV drug users, but transmission by other routes is possible.
Infection with hepatitis D can make the acute phase of hepatitis B unusually severe. It can cause an acute "exacerbation" in chronic hepatitis B carriers (superinfection), or cause a relatively aggressive course of chronic hepatitis B.

Hepatitis E
The hepatitis E virus is transmitted in the same manner as hepatitis A and produces similar symptoms. Hepatitis E does not cause chronic infection and has a similar prognosis to hepatitis A infection.
There is currently no vaccine available against hepatitis E.

Hepatitis F
Hepatitis F appears to be transmitted by the oral fecal route in a similar manner to hepatitis A and E although the epidemilogy of the virus has not yet been fully established.
In several cases of non-A-E hepatitis reported in western Europe, the United States and India, virus-like particles were observed in stool samples using an electron microscope. The virus called HAF consists of double-stranded DNA and is substantially different from HAV and HEV, both of which are RNA based.
Currently there is no serological test for diagnosing hepatitis F in cases of acute hepatitis but electron microscopy of stool samples may be of assistance after tests for other viruses have failed.

Hepatitis G
Available studies demonstrate that HGV-infection is a blood transfusion and parenterally transmitted disease; HGV-infection is relatively mild in most cases; among transfusion recipients, HGV-infection is about as frequent in those formally diagnosed with hepatitis as in those with only mild ALT elevations; HGV and hepatitis C virus can be transmitted simultaneously and result in persistent co-infection; HGV-infection can be persistent and cause chronic hepatitis. ; the prevalence of HGV is higher than that of hepatitis C virus and unrelated to the ALT status of the blood donor; and the role of HGV in fulminant hepatitis and hepatocellular carcinoma has not been delineated.
The viruses that cause hepatitis G (GBV-A, GBV-C and GBV-C) are RNA based and in the same family as hepatitis C.
As a relatively 'new' disease there is still much research to be performed and information is relatively scarce. At the time this document was written it appears that HGV has uncertain pathogenic potential.

Hepatitis C
The hepatitis C virus (HCV) was first characterized in 1989. Injection drug use is associated with at least half of HCV infections but you can also get HCV through tattooing and body piercing. In Canada, it is estimated that between 210,000 and 275,000 people are currently infected with hepatitis C, of whom only 30% know they have the virus. At present there is no vaccine against HCV.
Up to 90 per cent of infected persons carry HCV indefinitely. Over the long term, they are at risk of such illnesses as profound fatigue, cirrhosis, and liver cancer.
To prevent HCV, don't share needles or syringes.

BASIC INFORMATION ABOUT HEPATITIS C
• What is Hepatitis C?
• When was HCV discovered?
• How do people contract HCV?
• What are the symptoms of HCV?
• Are some people at greater risk of HCV infection than others?
• What is an Antigen?
• What is an Antibody?
• What diseases are associated with HCV infection?
• Can HCV be “cured”?
• If I'm cured, can I be reinfected with HCV?
• Can I be infected with more than one kind of hepatitis at the same time?
• What’s the difference between HAV, HBV and other forms of viral hepatitis?
• What are my chances of recovering from HCV infection without medical treatment?
• Why does HCV infection become chronic is so many people?

What is Hepatitis C?
The hepatitis C virus (HCV) is one of the leading known causes of liver disease in the United States. It is a common cause of cirrhosis and liver cancer (hepatocellular carcinoma or HCC) as well as the most common reason for liver transplantation. At least 4 million people in this country are believed to have been infected with HCV.
HCV damages the liver, one of the body's most important organs. Symptoms of both acute and chronic infections are easily confused with less serious and shorter-term illnesses. In fact, most infected people are relatively free of physical symptoms -- signs of liver damage may not occur for a couple of decades. Unfortunately, by the time the disease becomes apparent, liver damage can be considerable and even irreversible.
HCV is not related to the other hepatitis viruses (A-E) and diagnostic tests readily distinguish them. The virus is usually detected by an antibody test. Unlike many other infections, the presence of antibodies in the blood does not mean recovery.
Roughly 50 percent of chronic carriers do not even know they have hepatitis C, a disease that moves through specific stages of liver damage. Currently, diagnosis of the stage requires a liver biopsy, i.e., removal of a very small piece of the liver, and evaluation of an even smaller piece using a microscope. The rate of progression is highly individual and can be characterized as slow, medium or fast. For most people it is slow, i.e., after 20 years of chronic infection, only 20 percent of individual’s progress to cirrhosis. Alcohol and other hepatitis viruses hasten progression of the disease. Thus, if they know they are infected, individuals can help themselves by not using alcohol, and by getting vaccinated to prevent hepatitis A and B.

When was HCV discovered?
Following the identification of hepatitis A and hepatitis B, this disorder was categorized in 1974 as "non-A, non-B hepatitis." In 1989, the hepatitis C virus was identified and found to account for the majority of those patients with non-A, non-B hepatitis.

How do people contract HCV?
HCV is spread primarily by direct contact with human blood. For example, you may have gotten infected with HCV if:
You ever injected street drugs, as the needles and/or other drug "works" used to prepare or inject the drug(s) may have had someone else's blood that contained HCV on them.
You received blood, blood products, or solid organs from a donor whose blood contained HCV.
You were ever on long-term kidney dialysis as you may have unknowingly shared supplies/equipment that had someone else's blood on them.
You were ever a healthcare worker and had frequent contact with blood on the job, especially accidental needle sticks.
Your mother had hepatitis C at the time she gave birth to you. During the birth her blood may have gotten into your body.
You ever had sex with a person infected with HCV.
You lived with someone who was infected with HCV and shared items such as razors or toothbrushes that might have had blood on them.

What are the symptoms of HCV?
The symptoms of hepatitis C infection are often very mild. Some people with hepatitis C feel tired or have an upset stomach. Others may not have any symptoms at all. Even if you do not have any symptoms, hepatitis C is a serious illness. In most cases, once you have hepatitis C it never goes away. Over time, it can cause other health problems, such as cirrhosis (or scarring of the liver) and liver cancer. Finally, because it stays in your body, you can give hepatitis C to someone else.



Hepatitis C is often detected during blood tests for a routine physical or other medical procedure. The following symptoms could occur:
• jaundice
• abdominal pain (right upper abdomen)
• fatigue
• loss of appetite
• nausea and vomiting
• low-grade fever
• pale or clay-colored stools
• dark urine
• generalized itching

Are some people at greater risk of HCV infection than others?
Yes. The following people should be tested for HCV infection:
persons who ever injected illegal drugs, including those who injected once or a few times many years ago
persons who were treated for clotting problems with a blood product made before 1987 when more advanced methods for manufacturing the products were developed
persons who were notified that they received blood from a donor who later tested positive for hepatitis C
persons who received a blood transfusion or solid organ transplant before July 1992 when better testing of blood donors became available
long-term hemodialysis patients
persons who have signs or symptoms of liver disease (e.g., abnormal liver enzyme tests)
healthcare workers after exposures (e.g., needle sticks or splashes to the eye ) to HCV-positive blood on the job children born to HCV-positive women.

What is an Antigen?
An antigen is a substance (usually a protein or carbohydrate) that is recognized by the body and prompts the body to produce an immune response, usually in the form of antibodies. The Hepatitis C virus is an antigen.




What is an Antibody?
An antibody is large protein that is produced normally by specialized cells of the immune system after stimulation by an antigen, and acts specifically against an antigen in an immune response. The antibody proteins are also called immunoglobulins.
Some antibodies are produced abnormally, resulting in Autoimmune Disease. There are many different kinds of autoimmune disease, including a type of hepatitis. In these diseases, the immune system produces antibodies that attack normal, healthy tissue.
What diseases are associated with HCV infection?
A small percentage of persons with chronic hepatitis C develop medical conditions outside the liver (this is called extrahepatic). These conditions are thought to occur due to the body's natural immune system fighting against itself. Such conditions include: glomerulonephritis, essential mixed cryoglobulinemia, and porphyria cutanea tarda.

Can HCV be “cured”?
It depends on how you define the word “cured.” Some people, after completion of therapy for hepatitis C infection, achieved a Sustained Viral Response (SVR). This means that the level of hepatitis C virus in the blood has dropped to levels below the detection threshold of the currently available tests.
It is important to note that this does NOT necessarily mean that the virus is gone – it means that there is not enough virus present for the tests to detect. Studies have shown that people who achieve and maintain an SVR for several months after treatment have a very good chance of remaining “undetectable,” and will hopefully avoid the health consequences of chronic hepatitis C infection. These people will continue to have detectable antibodies to the hepatitis C virus. They may also be able to infect others with HCV, although the risk would be extremely small.
It is possible that some people who achieve an SVR during and after treatment will “relapse”, that is, the hepatitis C virus will return and chronic infection will resume.

If I'm cured, can I be reinfected with HCV?
Yes. Because of the ineffective immune response to hepatitis C infection, prior infection does not protect against reinfection with the same or different genotypes of the virus. For the same reason, there is no effective pre- or postexposure prophylaxis (i.e., immune globulin) available.
Can I be infected with more than one kind of hepatitis at the same time?
Yes. Persons with chronic liver disease who have never had hepatitis A should be vaccinated, as there is a higher rate of fulminant (rapid onset of liver failure, often leading to death) hepatitis A among persons with chronic liver disease. Persons who are either awaiting or have received liver transplants also should be vaccinated. Hepatitis B vaccine prevents hepatitis B disease and its serious consequences like hepatocellular carcinoma (liver cancer). Therefore, this is the first anti-cancer vaccine.
Hepatitis D is a defective single-stranded RNA virus that requires the helper function of HBV to replicate. Therefore, prevention of HBV infection by vaccination will also prevent HDV infection.

What’s the difference between HAV, HBV and other forms of viral hepatitis?
Although these viruses all result in hepatitis, they are genetically distinct and have significant differences in the method of infection, duration of infection, and long-term health consequences.
Hepatitis A is a liver disease caused by the hepatitis A virus. Hepatitis A can affect anyone. In the United States, hepatitis A can occur in situations ranging from isolated cases of disease to widespread epidemics.
Good personal hygiene and proper sanitation can help prevent hepatitis A. Vaccines are also available for long-term prevention of hepatitis A virus infection in persons 2 years of age and older. Immune globulin is available for short-term prevention of hepatitis A virus infection in individuals of all ages.
Hepatitis B is a serious disease caused by a virus that attacks the liver. The virus, which is called hepatitis B virus (HBV), can cause lifelong infection, cirrhosis (scarring) of the liver, liver cancer, liver failure, and death.
You get hepatitis B by direct contact with the blood or body fluids of an infected person; for example, you can become infected by having sex or sharing needles with an infected person. A baby can get hepatitis B from an infected mother during childbirth. Hepatitis B is not spread through food or water or by casual contact.
There are medications available to treat long-lasting (chronic) HBV-infection. These drugs work for some people, but there is no cure for hepatitis B when you first get it. That is why prevention is so important. Hepatitis B vaccine is the best protection against HBV. Three doses are commonly needed for complete protection.
Hepatitis D is a defective single-stranded RNA virus that requires the helper function of HBV to replicate. Therefore, prevention of HBV infection by vaccination will also prevent HDV infection.
Hepatitis E virus (HEV) is the major etiologic agent of enterically transmitted non-A, non-B hepatitis worldwide. Most outbreaks associated with fecally contaminated drinking water, and there is minimal person-to-person transmission. Cases in the United States usually have history of travel to HEV-endemic areas. Outbreaks of hepatitis E have occurred over a wide geographic area, primarily in developing countries with inadequate environmental sanitation.
What are my chances of recovering from HCV infection without medical treatment?

Of 100 people infected with HCV, 85 will develop chronic (long term) infection. About 15 out of 100 will not develop long-term infection.

Why does HCV infection become chronic is so many people?
People infected with HCV mount an antibody response to parts of the virus, but changes in the virus during infection result in changes that are not recognized by preexisting antibodies. This appears to be how the virus establishes and maintains long-lasting infection.


TRANSMISSION OF HEPATITIS C
• How do people contract HCV?
• Are some people more likely to get HCV than others?
• Can I get HCV by eating or drinking after someone else?
• What is the concentration of hepatitis virus in different body fluids / secretions?
• Can HCV be transmitted by tattooing or body piercing?
• Can a man's sperm infect a baby but not the mother?
• Can HCV be transmitted by using someone else's personal care items (toothbrushes, nail clippers, etc.)?
• Can I get HCV from a blood transfusion or blood products?

How do people contract HCV?
HCV is spread primarily by direct contact with human blood. For example, you may have gotten infected with HCV if:
You ever injected street drugs, as the needles and/or other drug "works" used to prepare or inject the drug(s) may have had someone else's blood that contained HCV on them.
You received blood, blood products, or solid organs from a donor whose blood contained HCV.
You were ever on long-term kidney dialysis as you may have unknowingly shared supplies/equipment that had someone else's blood on them.
You were ever a healthcare worker and had frequent contact with blood on the job, especially accidental needle sticks.
Your mother had hepatitis C at the time she gave birth to you. During the birth her blood may have gotten into your body.
You ever had sex with a person infected with HCV.
You lived with someone who was infected with HCV and shared items such as razors or toothbrushes that might have had his/her blood on them.

Are some people more likely to get HCV than others?
Yes. The following people should be tested for HCV infection:
• persons who ever injected illegal drugs, including those who injected once or a few times many years ago
• persons who were treated for clotting problems with a blood product made before 1987 when more advanced methods for manufacturing the products were developed
• persons who were notified that they received blood from a donor who later tested positive for hepatitis C
• persons who received a blood transfusion or solid organ transplant before July 1992 when better testing of blood donors became available
• long-term hemodialysis patients
• persons who have signs or symptoms of liver disease (e.g., abnormal liver enzyme tests)
• healthcare workers after exposures (e.g., needle sticks or splashes to the eye ) to HCV-positive blood on the job children born to HCV-positive women

Can I get HCV by eating or drinking after someone else?
HCV is not spread by sneezing, hugging, coughing, food or water, sharing eating utensils or drinking glasses, or casual contact.
What is the concentration of hepatitis virus in different body fluids / secretions?
Hepatitis A is found in high concentrations in feces, lower concentrations in serum, and even lower concentrations in saliva. HAV is not found in significant amounts in other fluids / secretions.
Hepatitis B is found in highest concentrations in blood, serum, and wound exudates. Semen, vaginal fluid and saliva contain moderate concentrations. Other body fluids / secretions (tears, urine, sweat, breast milk and feces) contain very low or undetectable levels of HBV.
Hepatitis C is found in greatest concentration in blood, and requires blood to blood exposure for transmission. HCV has been found in breast milk, but there are no documented cases of infection by breastfeeding. It is not known for certain if HCV is found in other body secretions.
Hepatitis D is found in blood, and requires blood to blood contact for transmission, but cannot develop into infection unless the person is already infected with Hepatitis B.

Hepatitis E is found in feces, and is transmitted by ingestion of contaminated food or water. Hepatitis E is rare in the United States and most U.S. cases occur among people who have traveled to areas where the disease is more common.

Can HCV be transmitted by tattooing or body piercing?
You can get infected with HCV if the tools that are used have someone else's blood on them, or if the artist or piercer doesn't follow good health practices, such as washing hands and using disposable gloves.

Can a man's sperm infect a baby but not the mother?
No. The transmission of HCV requires direct contact with infected blood.

Can HCV be transmitted by using someone else's personal care items (toothbrushes, nail clippers, etc.)?
Do not share toothbrushes, razors, or other personal care articles. They might have blood on them.

Can I get HCV from a blood transfusion or blood products?
The chances of transmission are less than 1 per million units transfused.