[Analysis of hepatitis C virus type and subtype distribution in Hungary]

Hepatitis C virus (HCV) shows great structural variability. Based on genome sequencing and phylogenetical analysis, 7 types and 67 subtypes can be differentiated with varying geographical distribution. It is very important to determine the HCV type/subtype prior to starting direct antiviral therapy (DAA), which has been available since 2014, because the type, dose and optimal length of medication depends on these.

In Hungary, the treatment of chronic HCV patients started in 1992 with the relevant special diagnostic tests being carried out in our Molecular Diagnostic Laboratory. Determination of the nucleotide sequence of the Hungarian HCV1b NS5A/PKR-BR region and the type and subtype distribution of Hungarian patients have already been carried out. The current summary discusses the results of 6092 chronic HCV patients (175 serotypes, 5917 genotypes) based on age, gender, regions and genotype distribution changes over the period between 1996 and 2017.

Serotyping (1996-1999). Genotyping: hybridization (2000-2016), real-time PCR (2016-; Cobas 4800 HCV GT).

Genotype distribution: GT1a: 5.6%; GT1b: 84.6%; GT1a + 1b: 5.1%; GT2: 0.1%; GT3: 1.8%; GT4: 0.1%; mixed: 1.6%; GT1 (non-differentiated subtype): 1,1%. Women/men ratio: 52%/48%. The most common age category is 50-60 years (37% of all cases). There was no genotype asymmetry among the four Hungarian regions and Budapest. Over time, the prevalence of genotype 3 increased from 1.6% to 2.8% and the number of patients under the age of 40 doubled.

There have been no substantial changes in the HCV type/subtype distribution in Hungary over the past 20 years, 1b remaining the most common. The introduction of real-time PCR method for genotyping has resulted in a major quality improvement including only a few mixed subtype results leading to more efficient drug selection. Orv Hetil. 2018; 159(Suppl 2): 2-8.