Assessment of Occurrence of Hepatitis B Virus Genotypes among Population in Provisional Capital and Federal Capital of Pakistan

Abstract

Aim: This study was aimed to figure out the prevalence of HBV genotypes among population in Pakistan. The areas which were not explored previously were studied in this research with special emphasis on finding out the new strains and sub genotypes of HBV. The genotypes were further confirmed by DNA sequencing. This study will help future researcher to study some other aspects of HBV related strains in Pakistan and also about its medical therapies. Study Design: The Hepatitis B surface antigen (HBsAg) and HBV DNA positive samples were collected in the first step and sent to Nuclear Medicine Oncology and Radiotherapy Institute [NORI], for further analysis. Place and Duration of Study: Polymerase Chain Reaction (PCR) lab, Nuclear Medicine, Oncology and Radiotherapy Institute [NORI], Islamabad, between September 2012 to February 2014. Methodology: A total of 450 Hepatitis B surface antigen HBsAg and HBV DNA positive samples including 100 from southern Punjab, 150 from Khyber pakhtoonkhwa (KPK), 100 from Islamabad and 100 from Quetta region were collected during the period of September 2012 to February 2014 and genotyped by type specific nested PCR primer pair method for 8 HBV genotypes from A through H. From the total 450 HBsAg positive samples, 41 were excluded from the study as they were either found to be negative for HBV DNA on or they had less than 100 IU/ml of viral load. So, out of the total 409 selected samples, 283 were of male gender and 126 of female with mean age of 35 years, ranging from 12 to 65 years. The patients were randomly selected irrespective of their age and gender and a written consent (parental consent in case of less than 18 years of age) was obtained. The study was approved by ethical review committee. Results: Our results showed Genotype D as the most prevalent and dominant genotype in all regions studied. Mix HBV genotype infections of genotype A with B & C, D with B and C constitute about 17 percent of all the samples. A mixture of genotype A+D was detected from the majority of the samples among mixed genotype group (62/69) which was followed by C+D (3/69). Genotype B and C are not common to be detected and were also found in smaller proportions. Positive PCR results were repeated twice for confirmation. Conclusion: Genotype D was identified and come out to be the most dominant genotype in Pakistani community showing sub-genotypes of D1 & D3 which is about 70.0% of the total sample size in our study. Genotype A and D are present as co-infection with each other and contributed as the second prevailing genotypic group.