Hepatitis C virus (HCV) genotypes are distributed differently depending on geography and route of infection. We characterized the distribution of genotypes in a large cohort of patients with chronic hepatitis C in the South-east of France and evaluated the relative prevalence according to time of acquisition. One thousand, one hundred-and-eighty-three patients who were anti-HCV-positive were studied. HCV genotype distribution has changed significantly from the 1960s to 2000. The prevalence of genotype 1b decreased from 47% before 1978 to 18.8% in the 1990s while the prevalence of genotype 1a and 3a increased during the same period from 18% and 15.3% to 28.8% and 26.3%, respectively. The logistic regression model showed that genotype 1a was significantly more common in patients infected through intravenous drug injection odds ratio ((OR): 2.08, P < 0.01) and after 1990 (OR: 1.98, P < 0.05). Genotype 1b was significantly less frequent in patients infected through intravenous drug injection (OR: 0.17, P < 0.001) and has decreased since 1978 (OR: 0.27, P < 0.001). Genotype 3a was independently associated with intravenous drug injection (OR: 6.1, P < 0.001) and tattooing (OR: 8.01, P < 0.001) and was more frequent in the 1979-90 period (OR: 2.05 and 1.74, P < 0.001 and P < 0.05). Our results show a modification of HCV genotypes distribution over the last four decades due to an increase of intravenous drug use (IVDU) contamination and an evolution of HCV genotypes distribution only in IVDU population characterized by a decrease of genotype 1b, an increase of genotype 3a from 1970 to 1990 and a higher increase of genotype 1a which is currently the predominant genotype in our population.

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Background & AimsDried blood spots (DBS) on filter paper have been successfully used to diagnose and monitor several infectious diseases. The aim was to investigate the performance of DBS in hepatitis B virus (HBV) diagnosis using commercial tests in comparison to standard methods.MethodsPaired DBS and plasma samples were collected from 200 patients: 100 patients with HBsAg negative status and 100 patients with HBsAg positive status. In the latter patient, HBeAg reactivity was tested. Ten samples of anti-HBs were collected from people vaccinated against HBV. We also studied 50 patients with positive HBV DNA viral load in plasma and 10 HBV DNA negative patients. HBV genotypes and gene polymerase mutations were determined in 10 randomly selected HBV-infected patients. The DBS sample consisted of 50 µL of whole blood, i.e. a 12-mm paper card.ResultsThe sensitivity thresholds of HBsAg and anti-HBs antibody were 0.30±0.08 IU/mL and 18.11±6.05 IU/mL, respectively, for DBS with 98% sensitivity and 100% specificity. Sensitivity was 98% and specificity 100% for the detection of HBV DNA on a blotter, considering an HBV DNA threshold of 914.1±157.8 IU/ml. Ten patients had an HBeAg positive status in plasma, all were detected positive using DBS. HBV genotyping and mutation detection were successfully performed on DBS, with full concordance between the 10 paired DBS and plasma samples.ConclusionThis study shows DBS is a reliable alternative to plasma specimens for quantifying and detecting HBsAg, anti-HBs, HBeAg and genotyping. DBS may increase the opportunities for HBV testing and treatment follow-up in hard-to-reach individuals.

Because of the use of viral kinetics during polyethylene glycol (PEG)-interferon-ribavirin therapy and the development of specific new anti-hepatitis C virus (anti-HCV) drugs, assessment of the efficacy of anti-HCV drugs needs to be based not on end-point PCR assays but on real-time PCR. The aim of this study was to determine if the two available commercial real-time PCR assays, the Abbott RealTime HCV assay and the Roche Cobas TaqMan HCV assay, can become the standard for HCV RNA quantification. We investigated the prognostic relevance of HCV RNA viral loads at baseline, week 4, and week 12 to a rapid and early virological response to antiviral therapy by using the two assays. Of 59 naïve patients chronically infected by HCV (41 infected with genotype 1) who were treated with ribavirin plus PEG-interferon alfa-2b for 48 weeks, 24 patients (41%) showed a sustained virological response (SVR). With the two assays, viral loads were highly correlated, irrespective of genotype (R 2 ‫؍‬ 0.94 for all cases). No difference in diagnostic value was found between the Abbott and Roche assays at week 4, with respective negative predictive values (NPVs) of 84% and 78% and positive predictive values (PPVs) of 62% and 56% (not significant), and at week 12, the respective NPVs were 91% and 90% and PPVs were 44% and 46% (not significant). At week 12, 83% (20/24) and 96% (23/24) of patients with SVR tested negative for HCV RNA by the Abbott and Roche assays, respectively (the difference is not significant). In conclusion, the high sensitivities and large dynamic ranges of the Abbott and Roche assays show that a single real-time quantitative PCR assay is fully adequate for clinical and therapeutic management of HCV.Based on pivotal trials in large multicenter studies, positive and negative predictions of sustained virological response (SVR) using viral load kinetics have been established and are now used for recommendations on antiviral therapy management by the American and European international consensus conference (4,6,9,14). The data for the proposed algorithm for the management of antiviral therapy in patients with chronic hepatitis C were mainly based on measurements of viral loads assessed by end-point PCR assays (NGI Superquant and Cobas Monitor Amplicor HCV 2.0) in centralized laboratories (3, 6, 13). General application may be difficult due to the lack of standardization of previous hepatitis C virus (HCV) RNA quantitation methods (15). The most common methods available for detecting and quantifying HCV RNA are based on PCR and on the signal amplification technique (branched DNA and Versant HCV RNA; Bayer). Two semiautomated PCR assays, the complete bioanalytical system (Cobas Monitor Amplicor HCV 2.0) and the LCx HCV RNA assay (Abbott), are commonly used by many laboratories. To make the quantitation of HCV RNA comparable among the different assays, the National Institute for Biological Standards and Controls and the World Health Organization (WHO) developed and certified a uniform standard for measuring HCV RNA in inte...

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