Contents

Intro to hepatitis C

Key points

  • Hepatitis C is a liver infection caused by the hepatitis C virus.
  • The immune system will try to clear the virus in the acute infection phase; if unsuccessful, the infection becomes chronic.
  • Once the infection becomes chronic, treatment is needed to cure it.
  • If left untreated, the virus causes inflammation, destroying healthy liver cells and causing the liver to replace them with scar tissue. This formation of scar tissue is called fibrosis and causes the liver to stiffen so it does not work as well. 
  • Over time, more of the liver gets replaced with scar tissue until nearly all of the liver is scarred; this is called cirrhosis.
  • The only way to know if a person has hepatitis C is for them to get tested.
  • Highly effective treatments cure more than 95% of people with hepatitis C in eight or 12 weeks.
  • There is no vaccination available to protect against hepatitis C.

The word hepatitis refers to an inflammation (-itis) of the liver (hepa-).

Hepatitis C is a specific liver infection caused by the hepatitis C virus.

The liver

The liver is the largest internal organ in the human body and performs over 500 essential processing functions. These include breaking down alcohol, drugs and other chemicals; regulating the supply of body fuel (glucose), hormones and essential vitamins and minerals; and making essential proteins for blood-transporting systems, blood clotting and immune function. The liver is also one of the few organs that can regenerate itself if injured.

The hepatitis C virus

The hepatitis C virus is an RNA virus. This means its genetic material is stored in the form of RNA instead of DNA. RNA tends to make more errors when it is making copies of itself than DNA does, resulting in different strains of hepatitis C. There are at least six major strains (genotypes) of the hepatitis C virus. The most common treatment for hepatitis C is pangenotypic medications called direct-acting antivirals (DAAs). The term pangenotypic means that these medications can cure any genotype of the hepatitis C virus. 

From acute infection to chronic disease

When the body is first exposed to the hepatitis C virus, the immune system tries to clear it (fight it off). This stage is called acute hepatitis C and can last up to six months. About one in four people (25%) will clear the virus from their body on their own during this time, in a process called spontaneous clearance. Cisgender (cis) women are more likely to spontaneously clear the virus than cis men; the exact reason for this is still being studied. If the virus is not cleared, the infection will not go away on its own. This is called a chronic hepatitis C infection. A person with chronic hepatitis C will need treatment to be cured.

Fibrosis and cirrhosis

When hepatitis C enters the bloodstream, it travels to the liver and attaches to liver cells. Inside these cells, the virus makes copies of itself, which can kill liver cells and cause inflammation. Over time, this ongoing inflammation causes the liver to replace liver cells with scar tissue. This formation of scar tissue is called fibrosis and causes the liver to stiffen so it does not work as well.

For most people, progression of liver damage is slow, often happening over 20–30 years. During this time, a person may not show any signs or symptoms, even though the hepatitis C virus is injuring the liver. Liver damage generally happens more slowly for cis women than it does for cis men (about half as fast). However, liver damage may happen more quickly for cis women who are going through menopause or who have completed their transition through menopause than for premenopausal women.

Over time, more and more of the liver becomes scarred. When most of the liver is scarred, this is called cirrhosis. Once cirrhosis has developed it initially results in compensated cirrhosis. In this stage the liver is still performing many of its functions. Many people with compensated cirrhosis experience few or no symptoms. However, if left untreated, eventually decompensated cirrhosis develops. Decompensated cirrhosis is when there is so much scar tissue that it is difficult for the liver to perform its essential functions properly. In this stage there is a significant risk of life-threatening complications, including fluid build-up in the abdomen (ascites), abdominal infections, internal bleeding and liver failure. With this type of cirrhosis, a liver transplant may be considered. Alcohol use can significantly speed up progression to cirrhosis, especially for individuals with hepatitis C.

People with cirrhosis have an increased risk of liver cancer called hepatocellular carcinoma (HCC), even after their hepatitis C is cured. People with decompensated cirrhosis will require additional support before starting treatment and regular monitoring for liver cancer for the rest of their life.

Hepatitis C outside the liver

The hepatitis C virus can also affect organs in the body aside from the liver. For example, it has been linked to an increased risk of kidney failure and prediabetes and diabetes. 

Hepatitis C testing

Hepatitis C is sometimes referred to as a “silent” disease because often there are no symptoms until the liver is severely injured and a person experiences significant health problems. The only way to know if someone has hepatitis C is to get tested. Two tests are usually required to diagnose a hepatitis C infection: a hepatitis C antibody test and a hepatitis C RNA test. For more information, see Testing.

The best way to prevent liver injury and complications of cirrhosis is to get treated and cured of hepatitis C as early as possible. 

Hepatitis C treatment and cure

Hepatitis C is curable! There are highly effective oral treatments that can cure more than 95% of people with hepatitis C in eight or 12 weeks. People with hepatitis C should speak with their healthcare provider about their treatment options. For more information, see Treatment and liver health.

Once someone is cured of hepatitis C (either through spontaneous clearance or treatment), the virus is no longer in their body, but they will always have hepatitis C antibodies in their blood. However, having hepatitis C antibodies does not make a person immune to getting a new hepatitis C infection. This means a person can be reinfected with hepatitis C if they are exposed to the virus again. There is no vaccination available to protect against hepatitis C. 

Transmission

Hepatitis C is transmitted primarily through blood-to-blood contact. When someone is exposed to the hepatitis C virus, it can enter their bloodstream and cause an infection. Today, most new hepatitis C infections in Canada happen when people reuse equipment to prepare and inject drugs. There are also other less common ways the virus can be passed. Hepatitis C is not passed through casual contact such as kissing, hugging or sharing utensils. For more information, see How hepatitis C transmission happens.

Resources for service providers

Resource for clients

Revised 2025.