Hepatitis C Genotype

The hepatitis C genotype is a type or "strain" of hepatitis C virus. There are 6 genotypes of hepatitis C around the world. In the United States, 3 genotypes are common:

• Genotype 1
• Genotype 2
• Genotype 3

These can be further specified as:

• Genotype 1a or 1b
• Genotype 2a or 2b
• Genotype 3a or 3b

The genotype of hepatitis C does not change over time. It needs to be tested only once.

Knowing the genotype of hepatitis C for each patient is very important information because hepatitis C treatment works differently for different genotypes. In general, genotype 1 is much more "resistant" to hepatitis C treatment and genotypes 2 and 3 are much more "sensitive" to treatment.

Genotype 1 (more difficult to treat)

Approximately 72% of Americans with hepatitis C have genotype 1 Chance of clearing hepatitis C virus is 42-46% Treatment usually lasts for 1 year Ribavirin dosage usually is higher than that required to treat other genotypes

Genotype 2 (easier to treat)

Approximately 10% of Americans with hepatitis C have genotype 2 Chance of clearing hepatitis C virus is 65-80% Treatment usually lasts for 6 months Ribavirin dosage usually is lower than that required to treat genotype 1

Genotype 3 (easier to treat)

Approximately 6% of Americans with hepatitis C have genotype 3 Chance of clearing hepatitis C virus is 65-80% Treatment usually lasts for 6 months Ribavirin dosage usually is lower than that required to treat genotype 1