Hepatitis C is a contagious liver disease caused by a virus. It is the most common blood-borne disease in the United States, and most people who have it do not know it.
Hepatitis C is spread by blood-to-blood contact, primarily through injectable drug use. There are immunizations against hepatitis A and B, but not for C. In order to prevent becoming infected with the hepatitis C virus it is necessary to prevent exposure.
If after being infected a person did not naturally clear the virus in six months, the infection would become chronic and only curable with medication. There are medications in all pill form to cure chronic hepatitis C infection.
Contents of this article:
You will also see introductions at the end of some sections to any recent developments that have been covered by MNT's news stories. Also look out for links to information about related conditions.
Fast facts on hepatitis C
Here are some key points about hepatitis C. More detail and supporting information is in the main article.
- Hepatitis C attacks the liver - the largest internal organ.
- Found worldwide, hepatitis C is the most common blood-borne disease in the United States, and the leading reason for liver transplant in the western world.1
- The most common method of transmitting hepatitis C virus is through injectable drug use (IDU) and sharing needles.
- The hepatitis C virus can survive outside the body at room temperature, on environmental surfaces, for up to three weeks.2
- The infection starts with an acute phase and can progress to a chronic phase in 80% of those infected.
- It is called a silent epidemic because most people do not feel sick when they initially get infected.
- Those with chronic infection can unknowingly pass the infection on to others.
- Baby boomers have a 5-fold risk of having hepatitis C as opposed to the rest of the population.3
- Early diagnosis can prevent health problems that may result from chronic infection.
- It is not uncommon for individuals to remain undiagnosed with hepatitis C until they show signs of end-stage liver disease.
- Chronic hepatitis C infection progresses to cirrhosis over a 20-year period in approximately 16% of those infected.4
What is hepatitis C?
Hepatitis is defined as inflammation of the liver. There are several strains of hepatitis with the most common being type A, type B, and type C.
Originally identified as non-A non-B, in 1989 the strain was subsequently named type C.
Hepatitis C virus (HCV), is the most widespread blood carried disease in the US, with an estimated 3.2 million persons chronically infected.5 Globally, 130-150 million have chronic infection.6 Unfortunately, 50% of those infected are unaware.7
What causes hepatitis C?
HCV is caused by a virus transmitted through blood-to-blood contact.8
A virus is a microscopic, infectious particle that contains nucleic acid (genetic instruction DNA or RNA). HCV is an RNA virus. Viruses lie in a dormant state until entering the living cell of a host, where it will then hijack the cell's hardware to replicate itself.
Hepatitis C is an RNA virus - a virus that has RNA (ribonucleic acid) as its genetic material.
Research suggests that chronic HCV infection consists of millions, or billions of actual viruses circulating within the body. At least six distinct HCV genotypes (named 1-6) and 70 subtypes have been identified.9
HCV is not transmitted through casual contact, respiratory droplets, sharing food, kissing, or through mosquito bites.10
For a blood-to-blood infection to occur, blood from an infected person must enter the body of someone who is not infected. By far, the biggest risk factor for becoming infected with HCV is injectable drug use; specifically sharing needles or equipment used to inject drugs.11
A speck of blood so small that it is not viewable to the naked eye can carry hundreds of hepatitis C virus particles. Cleaning with alcohol or rinsing with soap and water, even letting the needle and syringe air-dry for several days will not kill the virus.
Once it is injected into the body, even if on only one occasion, exposure has occurred and infection is quite possible. Around 30% of persons who inject drugs are infected with HCV within the first two years of using. After five years of IDU, 90% of users will be infected.12
Signs and symptoms of hepatitis C
Acute HCV infection is rarely diagnosed due to the lack of definitive symptoms. It is often referred to as a silent epidemic.13 The average time from exposure to symptom onset is 4-15 weeks.14
During this "acute infection period" - if symptoms are present - they are not considerably different to any other viral syndrome. Usually experienced is abdominal discomfort, nausea, fever, joint pain, fatigue, and infrequently jaundice (yellow tinge to skin and eyes) or clay colored stools.
HCV becomes chronic when the virus remains in the blood a year after the acute infection period. Unless treated with medication, the infection is lifelong.
Most people have no physical complaints with chronic infection, while some may have ongoing episodes of abdominal pain, persistent fatigue, and aching joints.
After a 25-30 year period, this chronic infection may result in significant scarring (fibrosis) of the liver, which can progress to cirrhosis (complete fibrosis), liver failure, and possibly liver cancer (hepatocellular carcinoma). Frequently it is not until the liver is on the verge of collapse that the damage is apparent.15
On the next page we look at tests and diagnosis of hepatitis C and the available treatment and prevention options for hepatitis C.