HCV genotypes and age distribution in patients of Vienna and surrounding areas.

BACKGROUND: Chronic hepatitis C (CHC) can result in liver cirrhosis and hepatocellular carcinoma. Determination of the hepatitis C virus (HCV) genotype/subtype may be of prognostic value to estimate the risk of development of liver cirrhosis. OBJECTIVE: The HCV genotype/subtype was determined in patients with CHC and possible associations with age, source of HCV transmission, duration of HCV infection, and development of liver cirrhosis were investigated. STUDY DESIGN: A total of 250 consecutive patients with CHC were studied. HCV genotypes/subtypes were determined with a commercially available assay based on the reverse-hybridization principle. Source of HCV transmission and duration of HCV infection were taken from the patient documentation and liver cirrhosis was diagnosed by clinical, biochemical, and sonographic data. RESULTS: HCV genotypes 1, 2, 3, 4, and 5 were found in 74.8, 2.8, 16, 5.2, and 0.4% of the patients. Most frequent subtypes were 1b (54%), 1a (15.6%), and 3a (15.6%). Patients with genotype 1 (mean, 52.8 years) or 2 (mean, 51.0 years) were significantly older than patients with genotype 3 (mean, 37.2 years) or genotype 4 (mean, 37.2 years). Patients with subtype 1b (mean, 58.1 years) were significantly older than patients with subtype 1a (mean, 40.8 years) or 3a (mean, 37.5 years). The main sources of HCV infection were intravenous drug abuse in 30.0% of all patients (genotype 1 in 53.3%; genotype 3 in 40%) or transfusion of blood and blood products in 21.6% of all patients (genotype 1 in 83.4%). The source of transmission, however, remained unknown in 44.8% of all patients. The prevalence of genotype 1 was significantly higher in patients with long duration (more than 20 years) of CHC. In none of the patients with genotype 2 or 3, duration of CHC for more than 20 years was observed. The prevalence of genotype 4 was significantly higher in patients with short duration (less than 10 years) of CHC. Liver cirrhosis was diagnosed in 13.6% of all patients (97.1% of patients with genotype 1). Patients with liver cirrhosis were significantly older compared to asymptomatic patients (mean, 63.8 vs. 51.3 years). CONCLUSION: HCV subtype 1b was found to be the main subtype in the investigated population and is currently the major contributor to liver cirrhosis. Patients infected with subtype 1a, however, are at comparable risk for development of liver cirrhosis. In future, subtype 3a and genotype 4 may also become an increasing problem.     

HCV genotypes in Morocco

To determine the hepatitis C virus (HCV) genotypes circulating in Morocco, virus isolates from 105 chronically infected and 19 hemodialysis patients were examined using the line probe assay. Genotypes 1 and 2 only were found among Moroccan patients. Subtypes 1b (47.6%) and 2a/2c (37.1%) were the most common, whereas subtype 1a (2.8%) was less common. Among the hemodialysis patients, only genotype 1 was found with a prevalence of 68.4% for subtype 1b and 15.8% for the subtype 1a. It was also shown that the HCV genotypes distribution varies with age in both studied populations. Subtype 1b was most prevalent among older patients, whereas subtype 2a/2c was mainly found among younger ones. Although Morocco belongs to the African continent, the circulating HCV strains are similar to those observed in some American and European 1997 countries. J. Med. Virol. 52:396–398, 1997. © 1997 Wiley-Liss, Inc.     

不同感染途径慢性丙型肝炎患者HCV基因型分布的差异

目的 探讨丙型肝炎病毒(HCV)基因型在中国部分城市输血与非输血途径感染者之间的分布。方法 对来自中国南北地区9个城市的慢性HCV肝炎患者的血清，用5′非编码区酶切分型方法进行HCV基因分型，分析HCV基因型在不同地区和感染途径之间的分布差异。结果 在219例慢性HCV肝炎血清中，有214例(97．7％)检测出HCV基因型，其中197例为单基因型HCV感染，主要的HCV流行株为1b(76．64％)和2a(18．22％)，并有5．14％的患者感染基因3b型，且首次在中国检测出4a型。HCV在中国南北地区城市的分布差异无显著意义，但输血感染者和非输血感染者之间的HCV基因型分布差异有显著意义，输血感染者中，93．88％为单基因型HCV感染，1b占76．87％，高于非输血途径感染患者中单基因型HCV感染百分率(86．57％)和1b的感染百分率(58．21％)，非输血感染者中的混合HCV基因型比例(13．43％)高于输血感染者(6．12％)。结论 中国南北部分地区的HCV基因型分布差异无显著意义，但经输血感染和非输血感染的慢性丙型肝炎患者之间的HCV基因型分布差异有显著意义。     

Prevalence and common genotypes of HCV infection in Sudanese patients with hepatosplenic schistosomiasis

A cross-sectional hospital based study was carried out at the National Center for Gastrointestinal and Liver Disease in Khartoum, Sudan to determine the prevalence, common genotypes and risk factors for hepatitis C virus infection in Sudanese patients with hepatosplenic schistosomiasis. A total of 176 patients with hepatosplenic schistosomiasis were tested for HCV antibodies and 4.5% of the samples were reactive. PCR was positive in 2.3% of cases and genotype 4 was the major genotype isolated with subtypes 4, 4e, and 4c/4d. It is concluded that HCV was of low seroprevalence in the study population and that parenteral antischistosomal therapy was not a significant risk factor in transmission of infection in the Sudan.     

Relevance of RIBA-3 supplementary test to HCV PCR positivity and genotypes for HCV confirmation of blood donors

HCV antibody screening of 624,910 blood donations resulted in 3,832 samples being referred for confirmation. All were tested by RIBA-3 with 2,710 negative, 945 indeterminate and 177 positive results. HCV RNA was detected by PCR in an average of 69.5% of RIBA-3 positives (4 bands 84.1%; 3 bands 74.1%; 2 bands 34.1%) and only 0.53% of RIBA-3 indeterminates. Eighty-four percent of samples with a total RIBA-3 band intensity score (maximum 16) of ≥8 were PCR positive compared with only 22% of those with a score of <8. Total mean band intensities for HCV genotype 1 samples (n = 65) were 13.2, genotype 2 (n = 17) 11.4 and genotype 3 (n = 65) 11.2 with type 1 samples showing greater reactivity with c100 and c33 antibodies. No PCR positive type 1 samples were found with RIBA-3 total band scores less than 8, no PCR positive type 2 samples less than 6, whilst PCR positive type 3 samples were found with scores as low as 2. NS5 indeterminates were the most common (40.2%) single band pattern but yielded no PCR positive samples, followed by c33 (23.3%) with one PCR positive and c100 (20.2%) with one PCR positive whilst c22 indeterminates were least common (16.3%) but included three PCR positive donors. All five RIBA-3 indeterminate PCR positive donors were type 3. © 1996 Wiley-Liss, Inc.     

Influence of hepatitis C virus (HCV) genotypes on HCV recombinant immunoblot assay patterns.

Ninety-six patients with chronic hepatitis C were studied. A second-generation recombinant immunoblot assay detected anti-NS4 antibodies significantly more often in patients infected by hepatitis C virus genotype 1 than in patients infected by other types. By a third-generation recombinant immunoblot assay, the prevalences of the four antibodies measured did not differ according to the hepatitis C virus genotype.     

Direct comparison of hepatitis C virus genotypes tested by INNO-LiPA HCV II and TRUGENE HCV genotyping methods.

BACKGROUND: Hepatitis C virus (HCV) is a major cause of chronic liver disease worldwide. It is associated with the development of end-stage liver disease and hepatocellular carcinoma. Studies have shown that patients infected with different genotypes of HCV may respond to interferon-ribavirin therapy differently and thus HCV genotype information is very important in helping physicians to better managing their patients. OBJECTIVES: Compare the end results of HCV typing of the two commercially available tests. STUDY DESIGN: TRUGENE Genotyping test (Visible Genetics) was used to analyze clinical specimens obtained from North America. The 5' NC was amplified with the Roche COBAS Amplicor HCV Monitor Test. Amplification products were blinded and genotyped by the TRUGENE HCV 5'NC method. Genotype results were compared with those obtained by the reverse hybridization based INNO-LiPA HCV II (Innogenetics) assay. Additional sequencing of the NS5B region was done to resolve discrepancies. RESULTS AND CONCLUSIONS: Among the total of 110 consecutively collected serum specimens submitted for HCV genotyping, 108/110 could be typed by the sequencing method and 107/110 were typable by LiPA HCV II method. Our experiences with the tests suggest that at type level, HCV genotype results are 100% concordant between the two tests studied for those 106 specimens successfully typed by both methods. More sensitive amplification, such as qualitative PCR, is needed to test specimens with viral load lower than 20000 IU/ml. Both tests can be easily adapted by a clinical diagnostic laboratory.     

Multiple infections with different HCV genotypes: prevalence and clinical impact.

BACKGROUND: In a HCV genotype 3a-infected patient, viremia with a different genotype (1b) was detected after 16 weeks of ineffective therapy. Serological typing revealed that this genotype had already been present prior to therapy. OBJECTIVES: To investigate the epidemiology of multiple HCV infections and the therapeutical consequences for patients superinfected with a new HCV strain. METHODS: Sera of 600 patients were screened for infection with multiple genotypes by using sequencing and a serological assay in parallel. RESULTS: Infection with two different HCV types was detected in 13 patients. The prevailing strain was genotyped by sequencing. From two of these patients additional sera were available which had been drawn up to 24 and 28 months prior to the current sample, respectively. Those early samples showed viremia with a HCV subtype that could not be detected by PCR afterwards. Only antibodies to the initial strain were detectable in the later samples. CONCLUSION: In patients serially infected by different HCV strains, one strain will prevail as the viremic virus. Under antiviral therapy, the displaced strain may become viremic again and may influence the outcome of therapy. Detection of inferior strains by serological assays before antiviral therapy may be important for choosing the adequate regimen.     

Interleukin 28A.rs12980602 and interleukin 28B.rs8103142 genotypes could be protective against HCV infection among Egyptians

Previous studies showed that interleukin (IL)-28B gene polymorphisms were associated with hepatitis C Virus (HCV) infection and treatment outcomes. We tested whether single-nucleotide polymorphisms (SNPs) in IL-28A and IL-28B are associated with HCV infection among Egyptians with HCV genotype 4 infections. We enrolled 144 chronic HCV patients, 72 spontaneously resolved HCV subjects, and 69 healthy controls. Four SNPs in IL-28A and IL-28B genes (IL-28A.rs12980602, IL-28B.rs12979860, IL-28B.rs8099917, and IL-28B.rs8103142) were genotyped. The most frequent IL-28B haplotype “TCT” was significantly more frequent in HCV-infected subjects than in HCV negative subjects (62.2% vs. 48.6%, respectively; p = 0.005). The frequency of IL-28A.rs12980602 “T” allele was significantly higher than the “C” allele in healthy controls compared to HCV-infected subjects (p < 0.001) with the “TT” genotype significantly higher in healthy controls compared to HCV-infected subjects (p < 0.001) with no association with viral load (p = 0.11) among chronically infected subjects. The results, also, confirmed the previous role of IL-28B SNPs in predicting HCV infection outcome. Importantly, IL-28B.rs8099917 “TT” genotype was significantly associated with low viral load in HCV-infected subjects, while the remaining three SNPs did not. The three IL-28B SNPs were in linkage disequilibrium (D′ > 0.68; r² > 0.43) for all comparisons in HCV patients, while there was no linkage disequilibrium of IL-28A polymorphisms and the three IL-28B SNPs. In conclusion, IL-28A.rs12980602 and IL-28B.rs8103142 TT genotype could be protective against HCV infection. Also, IL-28B.rs12979860, IL-28B.rs8099917, and IL-28B.rs8103142 SNPs predicted the outcome of HCV infection among genotype-4-infected Egyptians. Moreover, IL-28B.rs8099917 SNP affected the viral load in chronic HCV patients.

     

Effects of corticosteroids on HCV infection.

The risk factors for clinical recurrent hepatitis C in liver transplant recipients are not clearly defined. It has been suggested that the corticosteroids included in the treatments of patients undergoing allograft rejection might induce acute hepatitis by increasing HCV replication. In this study we investigated the effects of corticosteroid boluses on HCV viremia in liver allograft recipients treated for acute rejection. Since we had previously developed a model of HCV replication in peripheral blood mononuclear cells (PBMC) in vitro, we also studied the effects of corticosteroids on HCV replication in vitro. A transient peak of HCV viremia was observed in patients treated with corticosteroid boluses for an acute allograft rejection. In the cell cultures, corticosteroids induced an increase of the total amount of viral RNA detectable. Our results demonstrate that corticosteroids induce an increase of hepatitis C virus replication in vivo and in vitro.     

Changing distribution of norovirus genotypes and genetic analysis of recombinant GIIb among infants and children with diarrhea in Japan

A total of 402 fecal specimens collected during July 2003-June 2004 from infants and children with acute gastroenteritis, encompassing five localities (Maizuru, Tokyo, Sapporo, Saga, and Osaka) of Japan, were tested for the presence of norovirus by RT-PCR. It was found that 58 (14.4%) fecal specimens were positive for norovirus. Norovirus infection was detected throughout the year with the highest prevalence in December. Norovirus GII was the most predominant genogroup (98.3%; 57 of 58). The genotypes detected in this study were GI/4, GII/2, GII/3, GII/4, and GII/6. Of these, NoV GII/3 (known as the Arg320 virus cluster) was the most predominant genotype (43.9%), followed by NoV GII/4 (the Lordsdale virus cluster; 35.1%) and others. Two norovirus strains clustered with a "new variant designated GIIb" and a "new variant of GII/4" were found circulating in Japan for the first time. It was interesting to note that NoV GIIb and NoV GII/3 appeared to be the recombinant strains and the recombination site was demonstrated at the overlap of ORF1 and ORF2. The majority (96%) of the dominant norovirus strains were identified as the recombination of GII/3 capsid and GII/12 polymerase. The recombination in the NoV GIIb capsid gene at the breakpoint located at P1 domain was also identified. Obviously, NoV GIIb isolate in Japan had double recombination. This is the first report demonstrating the existence of different "new variants" co-circulating in Japanese infants and children with acute gastroenteritis.     

Assessment of HCV genotypes in Yunnan Province of Southwest China

Recently, we reported that the frequency of hepatitis C virus (HCV) genotypes and subtypes has rapidly changed among intravenous drug users (IDUs) in Yunnan Province over the last 5 years; this is especially true for subtype 6a which has increased in frequency from 5 to 15%. Here, we assessed 120 HCV-positive plasma samples from the general population (GP). HCV NS5B fragments were amplified and sequenced by PCR. We identified four HCV genotypes (1, 2, 3 and 6) and seven HCV subtypes (1b, 2a, 3a, 3b, 6a, 6n, and 6k) in this population. Genotype 3 was predominant, with a distribution frequency of 0.484, followed by genotype 1 (0.283), genotype 6 (0.133) and genotype 2 (0.100). HCV subtypes 3b (frequency 0.292) and 1b (frequency 0.283) were the most common subtypes. A comparison of the current data with previous results reported for IDUs showed that the distribution frequencies of genotypes 1, 2 and 6 were significantly different between patients in the GP and IDUs (P < 0.05). Among the HCV subtypes, the distribution frequencies of 1b, 2a, 6a, and 6n were significantly different between patients in the GP and IDU groups (P < 0.05). Moreover, Phylogenetic analyses showed that HCV subtype 6a strains isolated from IDUs and the GP were intermixed and not separately clustered. HCV subtype 6a was predominant not only among IDUs but also among those in the GP in the Guangdong Province and Vietnam. However, HCV subtype 6a was predominant only among IDUs and not among those in the GP in the Yunnan and Guangxi Provinces. Our results indicate that the HCV subtype 6a could rapidly spread across China.     

HCV infection in medical environments

Since the discovery of the hepatitis C virus(HCV), it has become evident that this infectious agent is a primary cause of posttransfusion and sporadic non-A, non-B hepatitis. Populations at risk for HCV infection include health care workers, infants born to HCV-infected mothers, hemodyalysis patients, and intravenous drug abusers. Because there currently is no HCV vaccine or specific immunoglobulin against HCV, prevention of exposure remains the only possibility for reducing HCV transmission and prevalence. However, the percentage of individuals who are positive for HCV antibody among health care workers is not significantly high, suggesting that health care workers are not at very high risk of HCV infection. Too much fear of HCV infection among the health care workers should be avoided.     

Spectrum of antibodies to HCV antigens in patients with different clinical patterns of chronic HCV infection

Correlations between the spectra of antibodies to HCV proteins represented by various antigenic determinants and clinical variants of chronic HCV infection were studied. Synthetic peptides core-16, NS4-20, and NS5-23 simulating the immunodominant regions of the core, NS4 and NS5 proteins and recombinant proteins core-114 and NS4-86 were used as antigens. The results indicate that if the serum of an HCV patients contains no IgG to both antigenic determinants of NS4 or to NS5 in combination with any core antigenic determinant, a clinical and biochemical remission is highly probable. Chronic hepatitis C is characterized by the presence of IgG in high titers to both antigenic determinants of NS4 protein, particularly in combination with anti-NS5 IgG in low titers or none at all, or high titers of anti-core-16 IgG in combination with high titers of anti-NS4-20 IgG.     

Accurate quantification of hepatitis C virus (HCV) RNA from all HCV genotypes by using branched-DNA technology.

In studies monitoring disease progression and therapeutic response, it is essential that the method used for hepatitis C virus (HCV) quantification not be influenced by genotypic variability. The branched DNA assay provides a reliable method for the quantification of HCV RNA. A modified set of oligonucleotide probes for the branched DNA assay was developed to enhance the efficiency of binding to genotypic variants of HCV. The improved branched DNA assay (HCV RNA 2.0) yielded highly reproducible quantification of hepatitis C virus RNA and displayed a nearly 600-fold dynamic range in quantification up to 120 Meq of HCV RNA per ml. The quantification limit was set at 0.2 Meg of HCV RNA per ml to ensure a specificity of > or = 95%. With this lowered quantification limit and the enhanced hybridization of the probes, the HCV RNA 2.0 assay exhibited a high level of sensitivity (96%) and was virtually unaffected by the genotypic variability of HCV. The HCV RNA 2.0 assay may be a useful tool for following HCV RNA levels throughout the course of disease, selecting patients for therapy, and evaluating therapeutic response.     

Changing prevalence of hepatitis B virus genotypes in Iceland

At present eight hepatitis B virus (HBV) genotypes have been characterized: A to H. The most common genotype in Northern Europe is genotype A. So far there is no record of the specific HBV genotype distribution in Iceland. Iceland has a small population whose homogeneity has changed due to increasing migration during the past decades. The distribution of HBV genotypes in Iceland was analyzed using sera from 170 Icelandic patients. The samples were obtained before 1989, during an HBV epidemic among intravenous drug users in 1989 to 1992 and after 1994. A fragment of the HBV S-gene was amplified, sequenced and subjected to phylogenetic analysis. Among samples derived before 1989 genotypes A, C, and D were found. Most of the samples diagnosed during the epidemic belonged to genotype D and a smaller portion to genotype A. This suggests that the epidemic was most likely caused either by an endogenous HBV strain or by a strain imported from Europe or the USA. Among samples obtained after 1994, genotypes A to E and G were found, but the majority were of genotypes A, C, and D. This is consistent with an increase in migration and immigration from regions in Asia and Africa during the past 10 years. Thus, the changing prevalence of HBV genotypes in a small isolated community such as Iceland reflects the influence of migration and increasing contacts with regions outside the Western World.     

Serological reactivity and viral genotypes in hepatitis C virus infection.

Patients infected with hepatitis C virus (HCV) were examined with four commercial HCV immunoblotting assays and for anti-GOR antibody to ascertain whether serological findings varied with the genotype of the infecting virus. The results indicate that patients infected with different HCV genotypes tend to show different immunoblotting profiles, mainly due to a low prevalence of antibodies to the viral region NS4 in patients infected with genotypes III and IV. Differences were more evident with second- than with third-generation assays. Patients infected with genotype IV exhibited a lower prevalence of anti-GOR antibody than patients infected with other genotypes.     

Analysis of HCV genotypes from blood donors shows three new HCV type 6 subgroups exist in Myanmar

The prevalence of hepatitis C virus (HCV) genotypes in Myanmar in comparison with the rest of Southeast Asia is not well known. Serum samples were obtained from 201 HCV antibody-positive volunteer blood donors in and around the Myanmar city of Yangon. Of these, the antibody titers of 101 samples were checked by serial dilution using HCV antibody PA test II and Terasaki microplate as a low-cost method. To compare antibody titers by this method and RNA identification, we also checked HCV-RNA using the Amplicor 2.0 test. Most high-titer groups were positive for HCV-RNA. Of the 201 samples, 110 were successfully polymerase chain reaction (PCR) amplified. Among them, 35 (31.8%) were of genotype 1, 52 (47.3%) were of genotype 3, and 23 (20.9%) were of type 6 variants, and phylogenetic analysis of these type 6 variants revealed that 3 new type 6 subgroups exist in Myanmar. We named the subgroups M6-1, M6-2, and M6-3. M6-1 and M6-2 were relatively close to types 8 and 9, respectively. M6-3, though only found in one sample, was a brand-new subgroup. These subtypes were not seen in Vietnam, where type 6 group variants are widely spread. These findings may be useful for analyzing how and when these subgroups were formed.