Three-Year Distribution Pattern of Hepatitis C Virus Genotypes in Northern Italy

Objectives: Hepatitis C virus (HCV) infection is a global public health problem affecting around 200 million people worldwide. HCV infection is a leading cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Considering that HCV displays a considerable genetic heterogeneity and efficacy, duration, and costs of therapy differ by genotype, the knowledge of pattern distribution of genotypes has relevant clinical implications. The aim of this study is to analyze the epidemiological profile of HCV genotypes in the most recent years in the area of Parma, Northern Italy. Methods: During the 2011-2013 period, 764 plasma or serum samples of HCV RNA-positive patients attending the University Hospital of Parma were subjected to HCV genotyping, by means of the Versant HCV Genotype 2.0 line probe assay (Siemens Healthcare Diagnostics Inc., Tarrytown, NY, USA). This assay allows the amplification and hybridization of genome fragments from genotypes 1-6 through genotype-specific probes adsorbed onto nitrocellulose strips. The accuracy and sensitivity of the employed assay are 99.4% and 96%, respectively, as reported by the manufacturer. Results: Of the 764 individuals analyzed, 296 (38.7%) were females (mean and median age of 56 ± 15.6 and 57 years, respectively) and 468 (61.2%) males (mean and median age of 47 ± 14.3 and 47 years, respectively). Genotype 1 (G1) group, composed of 396 individuals (41.4% females and 58.6% males), was predominant (51.8%), followed by G3 (21.9%), composed of 168 individuals (22.6% females and 77.3% males), and G2 (20%), composed of 153 individuals (52.3% females and 47.7% males). The leading subtypes were 1b (61.9% of G1 group), 2a/2c (66.6% of G2 group), and 3a (94% of G3 group). The subtypes 1a and 3a were more common in males than in females. The subtype 1b was prevalent in young and old people, whilst 3a in adults. Noteworthy, 4a/4c/4d, 4f, and 5a subtypes were also detected. Although the overall dynamics of HCV genotypes did not vary significantly throughout the examined period, the subtype 4a/4c/4d increased from 2011 (2.6%) to 2013 (4.5%). Conclusion: This study assesses that genotype 1b, historically the most prevalent in Italy, is also predominant in the studied population, followed by 3a. However, the detection of the less represented genotypes 4 and 5, which are mainly found in Africa, suggests that the presence of HCV-positive migrants and the secondary spread of HCV infection in the host population may affect the current trends of HCV genotypes distribution. The overall results highlight the need of detailed and continuous epidemiological surveillance in order to evaluate accurately the geographical and temporal distribution of HCV genotypes.