Recent trends in molecular epidemiology of Hepatitis C virus in Mardan, KPK Pakistan

To determine the genotypic distribution of HCV, frequency of risk factors involved in its transmission, and correlation of genotype with viral load in Mardan population which is the second largest city of Khyber Pakhtunkhwa (KPK), Pakistan. Blood samples of 1140 were collected from different regions of Mardan and major proportion of recruited patients were internally displaced people (IDPs), refugees, and slum dwellers. Complete patient's history was analyzed to assess the possible risks involved in HCV transmission. Viral genotype was determined by PCR (polymerase chain reaction) whereas, HCV RNA was measured by qRT-PCR. Data was analyzed using SPSS statistical software. Our results indicate 3a as the most abundant subtype in Mardan population followed by 3b, 2a, 2b, 4a, untypeable, mixed, 1a, and 1b. In contrast to previous findings, genotype 1 was the least prevalent genotype and the overall prevalence of HCV in Mardan population was significantly higher in females (n = 687, 60.2%) than males (n = 453, 39.7%). Significant difference between-genotypes and gender was observed in genotype 1 (p < .034) and genotype 3 (p < .004). The mean age was 44 (SD ± 9.51). The most frequently found mixed genotype was 3a + 1b and mixed genotype was more prevalent in males. The proportion of middle-aged people (41-49 years) was higher whereas, older and younger people were least infected with HCV. This is the first study that showed substantial correlation of genotype 3 with low and intermediate viral load in Mardan population. Moreover, high and extremely high viral load was associated with other genotypes. Our findings showed that most of the patients who experienced high and extremely high viremia in their blood were males and belonged to Takhat Bhai and Mardaan regions. There were significant difference in the prevalence of HCV genotype 3a (p = .001) and genotype 3b (p = .005) in different regions of Mardan. Pre-treatment viral load is significantly high (p 0.001) in tehsil Mardan patients infected with HCV genotype 3 as compared to other genotypes. Unsafe medical practices such as medical and dental surgeries, intravenous drug use, and blood transfusions were the main risk factors for HCV transmission in Mardan, KPK Pakistan. This study gives clear insights into the epidemiological status of HCV in Mardan population. Genotype 3 is correlated with low and intermediate viral load whereas high viral loads were revealed among patients infected with genotypes other than genotype 3. In the absence of better data and robust epidemiological information, this detailed analysis of HCV genotypes with special reference to risk factors, pretreatment viral load, gender, and age will provide the baseline data for development of optimal HCV eradication and preventive strategies.