Search

Using hepatitis C virus (HCV) and interferon (IFN) resistance as a proof of concept, we have devised a new method for calculating the effect of a drug on a viral population, as well as the resistance of the population's individual intrahost variants. By means of next-generation sequencing, HCV variants were obtained from sera collected at nine time points from 16 patients during the first 48 h after injection of IFN-α. IFN-resistance coefficients were calculated for individual variants using changes in their relative frequencies, and for the entire intrahost viral population using changes in viral titer. Population-wide resistance and presence of IFN-resistant variants were highly associated with pegylated IFN-α2a/ribavirin treatment outcome at week 12 (P = 3.78 × 10−5 and 0.0114, respectively). This new method allows an accurate measurement of resistance based solely on changes in viral titer or the relative frequency of intrahost viral variants during a short observation time. [ABSTRACT FROM AUTHOR]

Distinguishing between acute and chronic HCV infections is clinically important given that early treatment of infected patients leads to high rates of sustained virological response. Analysis of 2179 clonal sequences derived from hypervariable region 1 (HVR1) of the HCV genome in samples obtained from patients with acute (n = 49) and chronic (n = 102) HCV infection showed that intra-host HVR1 diversity was 1.8 times higher in patients with chronic than acute infection. Significant differences in frequencies of 5 amino acids (positions 5, 7, 12, 16 and 18) and the average genetic distances among intra-host HVR1 variants were found using analysis of molecular variance. Differences were also observed in the polarity, volume and hydrophobicity of 10 amino acids (at positions 1, 4, 5, 12, 14, 15, 16, 21, 22 and 29). Based on these properties, a classification model could be constructed, which permitted HVR1 variants from acute and chronic cases to be discriminated with an accuracy of 88%. Progression from acute to chronic stage of HCV infection is accompanied by characteristic changes in amino acid composition of HVR1. Identifying these changes may permit diagnosis of recent HCV infection. [ABSTRACT FROM AUTHOR]

Whether differences in the natural history of hepatitis C virus (HCV) can be explained by differences in the infecting HCV type is unknown. The aim of this study was to investigate whether the HCV type might influence the clinical outcome of infection. Study serum samples were assembled from 749 individuals enrolled into the UK HCV National Register from which data on clinical outcomes were extracted. HCV-RNA-positive specimens were genotyped and HCV-RNA-negative specimens serotyped. Logistic regression analysis was used to investigate the independent effect of HCV type on viral clearance by comparing patients who were HCV RNA negative ( n = 86) with those who were HCV RNA positive ( n = 508). The same method was used to investigate whether HCV type was associated with histological stage of liver disease. The prevalence of HCV type 1 among those who cleared infection was 69% and among those who remained HCV RNA positive was 51%: Type 1 infections were more likely to be HCV RNA negative than non-1 types (OR 0.47, 95% CI 0.29–0.78, P = 0.003). Type 1 infections were also more likely to be associated with histological stage scores above the median when compared with non-1 types (OR 2.03, 95% CI 1.07–3.83, P = 0.03). In conclusion, HCV type 1 infection was more often HCV RNA negative, suggesting that spontaneous clearance may occur more commonly with this type. Among the RNA-positive infections, type 1 infection may be more aggressive than types 2/3. [ABSTRACT FROM AUTHOR]

There is a variable geographic distribution in the prevalence of hepatitis C virus (HCV)-related oral lichen planus (OLP), which appears unrelated to either HCV genotype or HCV epidemiology. The present study investigated whether hepatitis G virus (HGV) co-infection may be a feature of patients with HCV-related OLP, which might explain these phenomena. HGV co-infection was detected in 6 of 39 Italian patients with HCV-related OLP, but the presence of HGV did not influence the clinical presentation of OLP. It is concluded that HGV co-infection is unlikely to influence the clinical detection of HCV-related OLP. [ABSTRACT FROM AUTHOR]

Examines the identification of Hepatitis C virus (HCV) for blood transfusion recipients in England. Factors influencing the outcome of HCV infection; Prevention of the risk of liver failure; Administration of long-term specialist management to transfusion recipients and blood donor with chronic hepatitis C infection.

Hepatitis C virus (HCV) has high genomic variability and since its discovery, six different "types" and an increasing number of "subtypes" have been reported. HCV genotype may influence viral replication, natural history of disease and response to therapy. Recently, an association between lichen planus (LP) and HCV infection has been suggested, as there is an increased frequency of HCV infection among some groups of patients with LP, in particular from Italy and Japan. These results have not been confirmed by other reports from different geographical areas. Since HCV genotypes have a heterogeneous geographical distribution, we have determined by restriction fragment length polymorphism the genotypes of 39 HCV-seropositive Italian patients with oral LP in order to establish whether the association between LP and HCV infection is influenced by HCV subtype. Of the 33 (84.6%) viraemic patients, 17 (51%) were infected by HCV subtype 1b, 9 (27%) were infected by HCV subtype 2a, 2 by subtype 1a and 1 by subtype 2b. In four cases the gel patterns were uninterpretable. This distribution of HCV genotypes is similar to that reported in recent studies of Italian HCV-seropositive patients of unknown LP status. It is concluded from this small sample that the association of lichen planus with HCV infection and its differential geographic distribution is unlikely to be due to infection by a particular HCV genotype. [ABSTRACT FROM AUTHOR]

Discusses transmission of hepatitis C virus in Western populations. High rates of sexual transmission in homosexual men; Risk to disease by needle sharing in drug use.