Host Factors Viral Factors
Age Less than 40 years Genotypes 2 and 3
Gender; female Viral Load < 2 million IU
Ethnicity; nonblack Lack of mutations in Interferon-sensitive determining region (ISDR)
Lack of liver fibrosis Decrease in E2 sequence homology with Protein Kinase R (PKR)
Anemic conditions Viral Kinetics; Rapid Decline with therapy
Immune response Increased duration of therapy
Interleukin-28 genetic polymorphism Co-infections
Sex hormones and menopause  
Organ transplant  
Insulin resistance  
Table 2: Various host and viral factors determining the effectiveness of interferon therapy in clearing the viral infection.