The hepatitis C virus (HCV) causes hepatitis C. There are different types or genotypes of hepatitis C, the most common being genotypes 1, 2, and 3. The genotype determines treatment, but generally, methods are effective in treating all genotypes.
Hepatitis C is a contagious liver disease caused by HCV. Hepatitis C may be acute or chronic, Hepatitis C is a contagious liver disease caused by HCV. Hepatitis C may be acute or chronic, and which genotype a person has determines their treatment.
This article looks at the different types of hepatitis C, how the genotypes differ, how to diagnose the type of hepatitis, treatments, and whether a person can have more than one type of hepatitis C.
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The United States Department of Veterans Affairs explains how the hepatitis C genotype is a type, or strain, of HCV. The most common HCV genotypes in the United States include:
- genotype 1
- genotype 2
- genotype 3
This further classifies into 1a and 1b, and 2a, 2b, and 2c. Of these subtypes, 1a, 1b, 2, and 3 are
How hepatitis C affects people
Most people with hepatitis C are asymptomatic (do not have symptoms). However, someone with acute hepatitis C may show symptoms within 1–3 months. Symptoms may include:
Chronic hepatitis C may only cause symptoms when complications have arisen, including:
- liver damage
- cirrhosis or scarring
- liver failure
- liver cancer
According to the United States Department of Veterans Affairs in the United States, approximately:
- 75% of people have genotype 1 (subtypes 1a or 1b)
- 20–25% of people have genotypes 2 or 3
- a small number of people have genotypes 4, 5, or 6
According to Treatment Action Group, all HCV genotypes cause the same amount of liver damage. However, people with genotype 1, particularly subtype 1b, are at greater risk of developing liver cirrhosis than people with other genotypes. Genotypes 1b and 3 may increase a person’s risk of developing liver cancer.
Most people with HCV tend to have a single genotype rather than multiple genotypes.
However, people who travel between regions where other HCV genotypes are more common may have exposure to different HCV genotypes, leading to a mixed infection.
According to an article in the Lancet,
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People should have relevant screening, testing, and treatments based on their HCV genotype.
Once a medical professional has diagnosed someone with HCV, the doctor will run further tests to assess the genotype and the viral load level. The viral load level refers to how much HCV is in the blood.
HCV genotypes
According to the United States Department of Veteran Affairs, the type of genotype a person has determines their treatment plan. This includes recommendations on specific antiviral medications and treatment duration.
These medications usually come as pills. Treatment duration usually lasts 12–24 weeks, depending on whether the person has cirrhosis.
Doctors sometimes prescribe a medication called ribavirin alongside antivirals. Doctors will not prescribe ribavirin to pregnant people or their partners, as it can cause congenital abnormalities or miscarriage.
To evaluate response to treatment, experts assess sustained virological response (SVR). The goal of treatment is to achieve SVR, where the virus is undetectable in the blood for 12 weeks or more.
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Genotype 3 may pose some challenges, and this type is generally associated with insulin resistance and risk for cancer. Genotype 3 is especially hard to treat in people who have:
- cirrhosis
- decompensated liver disease, a life threatening condition
- previously tried treatment
People with genotypes 2 and 3 may need treatment for a longer period.
Besides pan-genotypic DAA regimens, certain combinations of antivirals may work well — or even better — depending on the person’s genotype. For example, Zepatier (elbasvir/grazoprevir) works well for genotypes 1 or 4.
A doctor will tailor treatment on an individual basis, considering other factors too, including disease progression, possibility for treatment resistance, and side effect profile, among others.
Learn more about how hepatitis genotypes affect treatment.
Hepatitis C has different genotypes, the most common being genotypes 1, 2, and 3.
All genotypes cause the same amount of liver damage. However, people with genotype 1, particularly subtype 1b, are at greater risk of developing liver cirrhosis than people with other genotypes. Doctors assess which genotype a person has through blood tests to check their DNA sequences and viral load in the blood.
The WHO recommends pan-genotypic direct-acting antivirals (DAAs) for chronic hepatitis C regardless of the genotype.
Generally, people have one genotype, but if someone has traveled between regions where different genotypes are more common, they may have exposure to various HCV genotypes, leading to a mixed infection. However, this is unlikely to affect a person’s treatment.