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Template:Taxobox begin Template:Taxobox begin placement virus Template:Taxobox group iv entry Template:Taxobox familia entry Template:Taxobox genus entry Template:Taxobox species entry Template:Taxobox end placement Template:Taxobox end Hepatitis C is a form of hepatitis liver inflammation caused by a virus, the Hepatitis C virus (HCV). Before the virus was discovered, in 1989, the syndrome was initially referred to as a "non-A-non-B hepatitis". Aproximately 15-20% of individuals find themeselves able to curb the virus and develop immunity. Unfortunately most of the individuals will progress into chronicity with only about 15-20% showing early acute signs of the disease. For each 100 chronic Hepatitis C patients 20 will develop liver chirrosis (scaring of the liver) and 4 will progress into Liver Cancer. Hepatitis C infected 150 to 200 million people around the world and it is now the leading cause of liver transplant, Hepatocellular carcinoma and is the major cause of death among HIV co-infected patients.

Symptoms

In most cases, carriers with chronic hepatitis C infection have no symptoms. However, over time this blood borne virus can cause long term damage to the liver, including cirrhosis and hepatocellular carcinoma. Severe liver damage may not develop until 10-40 years after infection. Certain medical phenomena have been associated with the presence of hepatitis C, such as thyroiditis, cryoglobulinemia and some types of glomerulonephritis. Carriers of the virus may begin to develop symptoms after only a few years. Symptoms, when developed, are variable and dependent on individual carrier. They may include prolonged flu-like symptoms and any combination of the following: body aches, headaches, nightsweats, loss of appetite, diarrhea, fatigue, nausea, mild abdominal pain, upper right quadrant pain.

Most people are not aware that they carry the hepatitis virus until something causes them to require a physical exam, and then something routine is done, such as blood work. There are also cases where carriers have found out through blood donation or plasma donation that their blood carried a positive response to a HCV test.

There are several risk factors that qualify one for a higher risk of exposure to HCV virus. They include

Needle sharing.Those who inject drugs are at high-risk for getting hepatitis C because they may be sharing needles and other drug paraphernalia, which may be contaminated with HCV-infected blood. In fact, 60% to 80% of all IV drug users have hepatitis C infection.
Unprotected sex. Although HCV is not classed as a sexually transmitted disease, there is some transmission due to sexual activity. This is often as a result of infection with an actual STD. Many STDs cause sores or wounds around the genitals, and thus sexual activity will lead to the spread of HCV. It is important to note however, that the spread is due to blood-blood contact, rather than the presence of the virus in vaginal fluid or semen.
Multiple piercings or tattoos. Tattooing dye or needles used in tattooing or body piercing can carry HCV-infected blood from one customer to another if the tattoo/body piercing parlors do not use sterile techniques or supplies.

(Tattoos done non-professionally, as in a penal institution, are of great concern.)

Blood transfusions BEFORE 1992. Those who have had a blood transfusion before 1992 and hemophiliacs who have received clotting factor before that time are at risk because blood banks did not fully test the blood supply for hepatitis C before that year. Today, however, the risk of getting hepatitis C from a blood transfusion is almost zero.
Other risk factors include needlestick injuries, especially among health care workers, hemodialysis (equipment that filters blood may not be adequately sterilized between patients), and organ transplant before 1992.

Transmission

HCV is spread primarily by direct contact with human blood. Transmission through blood transfusions that are not screened for HCV infection, through the reuse of inadequately sterilized needles, syringes or other medical equipment, or through needle-sharing among drug-users, is well documented. Other modes of transmission such as social, cultural, and behavioural practices using percutaneous procedures (e.g. ear and body piercing, circumcision, tattooing) can occur if inadequately sterilized equipment is used. HCV is not spread by sneezing, hugging, coughing, food or water, sharing eating utensils, sexual or casual contact. (But note the remarks about unprotected sex and HCV further above!)

In both developed and developing countries, high risk groups include injecting drug users, recipients of unscreened blood, haemophiliacs, and dialysis patients.

In developed countries, it is estimated that 90% of persons with chronic HCV infection are current and former injecting drug users and those with a history of transfusion of unscreened blood or blood products.

In many developing countries, where unscreened blood and blood products are still being used, the major means of transmission are unsterilized injection equipment and unscreened blood transfusions. In addition, people who use traditional scarification and circumcision practices are at risk if they use or re-use unsterilized tools.

Virology

The hepatitis C virus is a single-stranded, enveloped, positive sense RNA virus in the flaviviridae family. When circulating in the bloodstream, it binds to receptors on liver tissue, it is thought that the virus attaches to the receptors CD81 and SR-BI, however as these molecules are found throughout the body, it is unknown what makes it liver specific.

Epidemiology

Hepatitis C infects an estimated 170 million persons worldwide and 4 million persons in the United States. There are around 35,000 to 185,000 new cases of infections a year in the United States. Co-infection with HIV is common and rates among HIV positive populations are higher. 10,000-20,000 deaths a year in the United States are from HCV; expectations are that this will increase, as those who were infected by transfusion before HCV test are expected to become apparent. An August 2003 Harper's articleTemplate:Fn by Wil S. Hylton estimated that "somewhere between 20 and 40 percent of American prisoners are, at this very moment, infected with hepatitis C."

Currently, serological tests are available to check for infection. In addition, PCR can be used for more sensitivity and to elucidate a genotypes for the infection. There are eleven groups, divided by locations. Genotype 1a is the most common in North America, and 1b in Europe.

The infection is spread by blood exchange and, less commonly, sexual contact. Before serological tests became available, it was often caused by the use of medical products derived from blood and by blood transfusion.

Though hepatitis A, hepatitis B, and hepatitis C have similar names (because they all cause liver disease) the viruses themselves are quite different. Unlike hepatitis A and B, there is no vaccine for hepatitis C.

Treatment

Current standard of care treatment is a combination of Pegylated Interferon alpha in combination with an antiviral drug named ribavirin; Current indication for treatment include patients with proven Hepatitis C Virus infection through qualitative and quantitative confirmation of the RNA of the virus, with persistent abnormal liver tests and confirmation of liver scaring through a liver biopsy depending on the Genotype of the virus. Studies have shown sustained cure rates ( Sustained Viral Response) of 75% or better in people with genotypes HCV 2 or 3 in 24 weeks of combination therapy, and about 50-60% in those with genotype HCV 1 and 4 in 48 weeks of therapy (the most difficult to treat. Current combination therapy can only be supervised by experienced physicians in the field of Hepatology and Infectious Disease and a substancial percentage of patients will experience a panoply of minor side effects ranging from flu like syndrome (the most common) to severe adverse events as anemia and other blood like disorders.

Individuals with Hepatitis C should be vaccinated for Hepatitis A and B if they have not yet been exposed to these viruses.

It is well known that alcohol makes HCV associated liver disease progress faster.

Hepatitis C co-infection with HIV

Approximately 40% of U.S. patients infected with HIV are also infected with the hepatitis C virus (HCV), mainly because both viruses are blood-borne. In other countries, co-infection is less common due to differing drug policies. HCV is one of most important causes of chronic liver disease in the U.S. It has been demonstrated in clinical studies that HIV infection causes a more rapid progression of chronic hepatitis C to cirrhosis and liver failure in HIV-infected persons. This is not to say treatment is not an option for those living with co-infection. The APRICOT international trial indicated that a svr (sustained viral response) was high in those with the genotype 2 & 3. Less favorable results where associated with genotype 1, however it became evident that should treatment with pegylated ribivirin-interferon not return a 2 log viral reduction after 12 weeks, the chance of treatment success is less than 1%.

Alternative and experimental therapies

Several "alternative therapies" purport to reduce the liver's duties, rather than treat the virus itself, thereby slowing the course of the disease or keeping the quality of life of the person. As an example, extract of silybum marianum and licorice are sold for their HCV related effects; the first is said to provide some generic help to hepatic functions, and the second to have a mild antiviral effect and to raise blood pressure.

It is always important to tell your doctors all medications you are currently taking as well as herbal ones. If you are a post transplant patient it is even more important to notify your doctor of these herbal medications because silybum marianum (aka silymarin or Milk thistle) may inhibit the metabolism of certain drugs[1].

There are new drugs under development like the protease inhibitor NM 283,BILN 2061 or VX 950 that are looking promising but are all in early phase of development[2] [3]. Unfortunately, the BILN 2061 had to be discontinued due to safety problems early in the clinical testing. Some more modern new drugs that provide some support in treating HCV are Albuferon, Zadaxin, and DAPY. Antisense Morpholino oligos have shown promise in preclinical studies [4] and are beginning human clinical trials in 2005.

All of these are not approved remedies and have not yet demonstrated their efficacy in clinical trials.

Immunoglobulins against the Hepatis C virus exist and newer types are under development. Thus far, their roles have been unclear as they have not been shown to help in clearing chronic infection or in the prevention of infection with acute exposures (ie. needlesticks). They do have a limited role in transplant patients.

Prominent patients

Celebrities Naomi Judd and Pamela Anderson have famously been infected with hepatitis C and gone public with their experiences.

Francisco Varela, biologist, recorded his experiences, including a liver transplant, in "Intimate Distances"Template:Fn.

Notes

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 == Hepatitis C co-infection with HIV ==
-Approximately 40% of U.S. patients infected with HIV are also infected with the hepatitis C virus (HCV), mainly because both viruses share the same routes of transmission. HCV is one of most important causes of chronic liver disease in the U.S. It has been demonstrated in clinical studies that HIV infection causes a more rapid progression of chronic hepatitis C to cirrhosis and liver failure in HIV-infected persons. This is not to say treatment is not an option for those living with co-infection. The APRICOT international trial indicated that a svr (sustained viral response)  was high in those with the genotype 2 & 3. Less favorable results where associated with genotype 1, however it became evident that should treatment with pegylated ribivirin-interferon not return a 2 log viral reduction after 12 weeks, the chance of treatment success is less than 1%.
+Approximately 40% of U.S. patients infected with HIV are also infected with the hepatitis C virus (HCV), mainly because both viruses are blood-borne. In other countries, co-infection is less common due to differing drug policies. HCV is one of most important causes of chronic liver disease in the U.S. It has been demonstrated in clinical studies that HIV infection causes a more rapid progression of chronic hepatitis C to cirrhosis and liver failure in HIV-infected persons. This is not to say treatment is not an option for those living with co-infection. The APRICOT international trial indicated that a svr (sustained viral response)  was high in those with the genotype 2 & 3. Less favorable results where associated with genotype 1, however it became evident that should treatment with pegylated ribivirin-interferon not return a 2 log viral reduction after 12 weeks, the chance of treatment success is less than 1%.
 ==Alternative and experimental therapies==