There are 185 million people worldwide (2.8%) infected with the hepatitis C virus. The virus has seven different strains called genotypes—numbered 1 through 7. The variance (nucleotides) between each genotype is approximately 30-35%. There are also variances (nucleotides) of about 15% difference between each genotype—these are called subtypes, further classified by alphabetic letters, i.e., genotype 1a, 1b. The test to find out the genotype and subtype is a blood test.
Subtype information is necessary in regards to HCV antiviral treatment. Some medications work better with some of the HCV inhibitors than with others. This is one of the reasons that multiple HCV inhibitors (protease inhibitors, NS5A inhibitors, polymerase inhibitors) are being combined to treat hepatitis C.
Labels: HCV Subtype, treatment information