Molecular epidemiology of hepatitis C virus genotypes and subtypes among injecting drug users in Hungary.

The aim of this study was to determine the geographical distribution of hepatitis C virus genotypes/subtypes among people who inject drugs (PWID) recruited at 22 needle exchange sites and drug outpatient services in all seven Planning and Statistical Regions of Hungary. Of 198 such PWID, 147 (74.2%), 45 (22.7%) and six (3.0%) carried genotype 1, 3 or 4, respectively, and 31 (72.1%) of the 43 genotype 1 sequences were of subtype 1a. Genotype 3 was significantly more prevalent in provincial towns than in the capital, Budapest. Injecting for a longer period and an older age both correlated with a higher prevalence of genotype 3, suggesting possible future changes in genotype distribution. The distributions of hepatitis C virus genotypes/ subtypes differed significantly between the tested PWID and the general population. The identification of genotype 3 reflected its worldwide occurrence among PWID. Our results underline the importance of genotyping before treatment, especially among people who have ever injected drugs in Hungary.

Prevalence and genotyping of group 3 torque teno viruses detected in health care workers in Hungary.

Torque teno viruses (TTVs) are classified into the Anellovirus genus of the Circoviridae family. In addition to TTV isolates, TTV genogroup 3 also includes the 8 virus strains known as SENV-A to H. In this study, the prevalence of TTV group 3 viruses and that of SENV-D and H in particular were determined among the staff of a hospital in Budapest. Viruses were genotyped using type-specific PCR primers and by cloning and sequencing of PCR products. Frequency of infection with TTV group 3 was high among both the hospital staff and the control group. Prevalence of SENV-H was similar in the two groups, but SENV-D infection was significantly more common in the study group than in controls. Sequencing of PCR products showed that viruses closely related to isolate TUS01 are common in Hungary. Several sequences could not be genotyped and may represent a previously undescribed genotype within the genogroup. TTV group 3 sequences detected in the serum samples of a symptomless health care worker were followed-up for 15 years. Some strains persisted for up to 10 years, while others caused transient infections and could be detected in only one of the samples. Results showed that TTV infection, superinfection, and viral clearance often occur over the years without apparent symptoms.

Variability of the PreS1/PreS2/S regions of hepatitis B virus in Hungary.

Infection with the hepatitis B virus can occur perinatally, parenterally, or sexually, and it can cause acute or chronic liver diseases. Phylogenetic analysis of the virus has led to its classification into eight genotypes (A-H), which show a characteristic worldwide distribution. The aim of this study was to reveal the HBV genotypes present in Hungary and to investigate a nosocomial and an intrafamilial outbreak. The collected samples were tested by nested PCR, and a 650-nucleotide-long segment of the preS1/preS2/S region was sequenced. As no previous genotype data were available from Hungary, sera of 24 HBsAg-positive patients were collected from different regions of the country. They also served as control samples for the molecular epidemiologic study. Nineteen of them carried genotype D of hepatitis B virus, and five of them carried genotype A. Twenty-nine patients from a haemato-oncology unit were affected in a nosocomial outbreak. The patients had haematological and/or oncological diseases, most of them were immunosuppressed. In twenty-eight cases, based on phylogenetic analysis of the viruses, there was presumably a common source of infection, and an epidemiological investigation showed that the infections seemed to be hospital-acquired. In the intrafamilial outbreak, two asymptomatic carrier children infected their foster mother. The three sequences were totally identical.