HCV genotypes in patients with chronic hepatitis C in Croatia

Molecular Epidemiology and Baseline Resistance of Hepatitis C Virus to Direct Acting Antivirals in Croatia

Molecular epidemiology of hepatitis C virus (HCV) is exceptionally complex due to the highly diverse HCV genome. Genetic diversity, transmission dynamics, and epidemic history of the most common HCV genotypes were inferred by population sequencing of the HCV NS3, NS5A, and NS5B region followed by phylogenetic and phylodynamic analysis. The results of this research suggest high overall prevalence of baseline NS3 resistance associate substitutions (RAS) (33.0%), moderate prevalence of NS5A RAS (13.7%), and low prevalence of nucleoside inhibitor NS5B RAS (8.3%). Prevalence of RAS significantly differed according to HCV genotype, with the highest prevalence of baseline resistance to NS3 inhibitors and NS5A inhibitors observed in HCV subtype 1a (68.8%) and subtype 1b (21.3%), respectively. Phylogenetic tree reconstructions showed two distinct clades within the subtype 1a, clade I (62.4%) and clade II (37.6%). NS3 RAS were preferentially associated with clade I. Phylogenetic analysis demonstrated that 27 (9.0%) HCV sequences had a presumed epidemiological link with another sequence and classified into 13 transmission pairs or clusters which were predominantly comprised of subtype 3a viruses and commonly detected among intravenous drug users (IDU). Phylodynamic analyses highlighted an exponential increase in subtype 1a and 3a effective population size in the late 20th century, which is a period associated with an explosive increase in the number of IDU in Croatia.

The "hidden" epidemic: a snapshot of Moroccan intravenous drug users

Background

Hepatitis C virus is a persistent epidemiological problem, with an estimated 170 million individuals infected worldwide, and the leading cause of asymptomatic chronic infection, liver cirrhosis and hepatocellular carcinoma. Injection drug users (IDUs) have the highest seroprevalence as compared to chronic hemodialysis and transfusion patients, and this cohort remains the most under-studied high-risk group in North Africa to date. This study first sought to characterize the demographic, epidemiological, and genotypic profile of a total sample size of 211 chronically-infected IDUs living in the Tangier region of Northern Morocco, and secondly to contrast this to other chronically-infected patients, in order to uncover possible discrepancies.

Results

The general ‘profile’ of local IDUs marks a stark contrast to chronically-infected HCV Moroccan patients, other African countries, and neighboring European countries. The majority of Moroccan drug users were found to be middle-aged and celibate. A relatively high seroprevalence was found among drug users (60%), and this increased with age. The majority of drug users shared their needles and this hold implications for transmission, as seropositive status was significantly different between those users that shared vs. those that did not share their needles. In addition, IDUs exhibited genotypes 1a and 3a predominantly, as compared to the predominant 1b and 2a/2c genotypes found in chronically HCV-infected patients. The IDU genotypic profile closely matches the one in other European countries (Portugal, Spain, France, and Italy), which are invariably speculated as the potential source of currently-circulating genotypes in Moroccan IDUs.

Conclusion

These findings have implications for disease prevention, transmission and treatment, as this distinct IDU subgroup cannot be collectively pooled along with other HCV-positive high-risk groups. Local government, practitioners, and health institutions should take this into account when treating, prescribing antiviral therapy, and designing preventative public health campaigns.

Hepatitis C virus genotypes in chronic hepatitis C patients and in first time blood donors in northeastern Bosnia and Herzegovina

Prevalence of hepatitis C virus (HCV) genotypes in Bosnia and Herzegovina (B&H) is an issue that is not sufficiently researched and there is a need for studies that would explore this in detail.The aim of this study was to determine the distribution of HCV genotypes in the group of patients with chronic hepatitis C and also in the group of first time blood donors that tested positive for anti HCV antibodies during the blood screening process. Our secondary goal was to compare the proportions of HCV genotypes between these two groups.We analyzed 75 blood samples of patients with confirmed chronic hepatitis C. We also analyzed 13/16082 blood samples of first time blood donors found to be HCV positive during the blood screening process. We also determined HCV genotype in HCV RNA positive samples.We have found that genotype 1b was more prevalent in chronic hepatitis C patients (52/75; 69,3%) than in first time blood donors (6/13; 46,1%), however this difference was not statistically significant (c2=1,721; df=1; p=0,19). Genotype 1a was more prevalent in the group of first time blood donors (3/13; 23,1%) than in the group of chronic hepatitis C patients (3/75; 4%), but this was also with limited statistical significance (c2=3,71; df=1; p=0,054). We have not found any significant difference in prevalence of genotypes 1a (p=0,2) and genotypes 3 (p=0,70) when compared between chronic patients (3/75 and 16/75; respectively) and first time blood donors (3/13 and 4/13; respectively). Our study confirmed domination of genotype 1b in the region of northeastern B&H which is in accordance with HCV genotype prevalence in other countries in our part of Europe.

Hepatitis C virus genotypes in Serbia and Montenegro: The prevalence and clinical significance

AIM: To investigate the prevalence of hepatitis C virus (HCV) genotypes in Serbia and Montenegro and their influence on some clinical characteristics in patients with chronic HCV infection.

METHODS: A total of 164 patients was investigated. Complete history, route of infection, assessment of alcohol consumption, an abdominal ultrasound, standard biochemical tests and liver biopsy were done. Gene sequencing of 5’ NTR type-specific PCR or commercial kits was performed for HCV genotyping and subtyping. The SPSS for Windows (version 10.0) was used for univariate regression analysis with further multivariate analysis.

RESULTS: The genotypes 1, 2, 3, 4, 1b3a and 1b4 were present in 57.9%, 3.7%, 23.2%, 6.7%, 6.7% and 1.8% of the patients, respectively. The genotype 1 (mainly the subtype 1b) was found to be independent of age in subjects older than 40 years, high viral load, more severe necro-inflammatory activity, advanced stage of fibrosis, and absence of intravenous drug abuse. The genotype 3a was associated with intravenous drug abuse and the age below 40. Multivariate analysis demonstrated age over 40 and intravenous drug abuse as the positive predictive factors for the genotypes 1b and 3a, respectively.

CONCLUSION: In Serbia and Montenegro, the genotypes 1b and 3a predominate in patients with chronic HCV infection. The subtype 1b is characteristic of older patients, while the genotype 3a is common in drug abusers. Association of the subtype 1b with advanced liver disease, higher viral load and histological activity suggests earlier infection with this genotype and eventually its increased pathogenicity.

Hepatitis C virus (HCV) 5′NC sequence variants and their association with hepatitis C risk groups

BACKGROUND

Genotype distribution of hepatitis C virus (HCV) is relatively uniform in Prague, Czech Republic. Unlike the other developed countries where HCV genotype 3 is increasingly associated with injection drug users (IDU), subtype 1b remains the most prevalent HCV subtype in Prague, regardless of risk factors.

OBJECTIVE

We wished to determine if subtype 1b strains could be further differentiated by comparing the conserved 5'NC sequences of the strains infecting IDU and non-IDU populations.

STUDY DESIGN

All prospectively collected serum samples that were HCV RNA positive were genotyped according to the 5'NC and NS5b regions. All 5'NC sequences were further analyzed for new mutations and these data were compared to patient epidemiologic information.

RESULTS

We found eight 5'NC sequence variants among 96 specimens tested. Further analysis of subtype 1b strains showed that a variant with a nucleotide insertion at -138 positions was found only among non-IDU subjects, while the variant with T-->C substitution at -94 was found only among the IDUs.

CONCLUSIONS

These observations suggest that the current HCV transmission between the IDU and non-IDU populations is uncommon, and may reflect the beginning of divergence of HCV genotypes in the IDU population in Prague.

Infrequent reinfection after successful treatment for hepatitis C virus infection in injection drug users

We followed-up 18 injection drug users for a mean of 33.8 months (range, 4-55 months) after successful treatment for hepatitis C virus (HCV) infection. Fifteen (83%) of the patients remained HCV RNA-negative, 1 patient was not tested, and 2 patients had test results positive for HCV RNA. The estimated rate of reinfection as a result of injection drug use was 0-4.1 cases per 100 person-years (cumulative incidence, 0%-12.6% at 48 months after completion of treatment). Of 50 patients originally treated, 15 (30%) were HCV RNA-negative 3 years later.

Genotypic and epidemiologic characteristics of hepatitis C virus infections among recent injection drug user and nonuser populations

The recent surge in injection drug use (IDU) in Prague, Czech Republic, provided an opportunity to compare the distribution of hepatitis C virus (HCV) genotypes among recent injection drug users and nonusers. We provide evidence that the most common HCV subtype, 1b, has been circulating in Prague longer than the other subtypes but that IDU practice has magnified its recent prevalence, and that the primary drug of choice among IDU subjects appears to influence the prevalence of a particular HCV subtype.

Hepatitis C virus infection in Eastern Europe

This analysis aims to summarise the available information on the incidence, prevalence and characteristics of hepatitis C virus (HCV) infection in countries in Eastern Europe.

METHODS

A questionnaire was prepared on the epidemiology and diagnosis of HCV infection and sent to national experts in the field. Further information was obtained from publications in international and national scientific journals. The incidence of acute hepatitis C in different countries for 1997 varied between 2.3 and 9.0 per 100 000 population with a trend towards increasing numbers of cases in several countries over the last few years. The prevalence of anti-HCV in blood donors ranged between 0.7% and 4.9%. The most frequent routes of transmission of HCV appear to be diagnostic and therapeutic procedures in the health care setting and/or intravenous drug use. Cumulative data on HCV genotype distribution based on 1774 patients demonstrate a large predominance of genotype 1b, which is found in between 51% and 92% of patients with HCV infection. There is a high prevalence of HCV infection in Eastern Europe. Further studies with larger groups of patients and especially including molecular diagnostic assays are needed to better define the characteristics of HCV infection, its natural course and the impact of host and viral factors on the HCV-induced liver diseases. These will have a major role for adequate selection and monitoring of the patients' treatment.

Chronic hepatitis C in Sweden: genotype distribution over time in different epidemiological settings

Hepatitis C virus (HCV) strains are divided into 6 genotypes and several subtypes. Recent studies reported a change in the relative frequency of genotypes within certain regions. We studied the HCV genotype in 312 Swedish patients with chronic hepatitis C, using a core region primer-specific PCR, and grouped the patients according to parenteral risk factors. The date of infection could be estimated in 127 cases. Genotypes 1a (35%) and 3 (31%) were the most common genotypes, followed by genotype 2 (17%), while only 6% had genotype 1b. Genotype 3 was relatively more frequent among subjects infected sexually or by intravenous drug use. The genotype distribution was different from that in studies from other parts of the world, with a lower frequency of genotype 1 (especially 1b) and a higher frequency of genotype 3. The frequency of genotype 1b has decreased and genotype 3 increased over time. The reasons for a different distribution of genotypes in Sweden, compared with other countries, might be a relatively recent introduction of HCV into the population, or a different pattern of transmission.