Prevalence of hepatitis C virus genotypes in chronic infected patients, southern Iran

Introduction and objective: Chronic infection with hepatitis C virus (HCV) is a major cause of cirrhosis and hepato-cellular carcinoma. Since response to anti-viral therapy in sufferers depends on HCV genotypes, determination of such genotype is of great significance to the treatment. This study seeks to estimate the HCV genotype prevalence in Shiraz, southern Iran and help specify the treatment course.

Materials and methods: A RT-PCR available kit with genotypes specific primer sets for major HCV genotypes (1a, 1b, 2 and 3a) was used. These primers amplified different parts of 5' un-translating region-core region of HCV genome. Genotyping test was performed for 634 patients with positive qualitative RT-PCR results.

Results: Of the 634 studied participants, 550(86.8%) were male and 84(13.2%) were female. Two hundred fifty nine (40.9%) of them were infected with 3a, 137(26.2%) with 1a, 55(8.7%) with 1b and 15(2.4%) with genotype 2 of hepatitis C. Mixed infection was found in 12 patients [1a+3a in 5(0.8%), 1a+1b in 4(0.6%) and 1a+2 in 3(0.5%)]. The extracted nucleic acid from 156(24.6%) samples did not react to the primer sets. This might be due to the presence of a genotype other than the above, or no sufficient copy of the virus.

Conclusion: The results revealed the highest level of infection belonging to 3a followed by 1a. Since a considerable proportion of chronic hepatic C infected patients were intravenous drug abusers in the region; genotype 3a appears to be more prevalent among this group.

Significance and impact of the study: The present study determined some critical information about the distribution of HCV genotypes in southern Iran.