Investigation of the pattern of hepatitis C virus sequence diversity in different geographical regions: implications for virus classification

Mellor, Janet; Holmes, Eddie; Jarvis, L M; Yap, P. L.; Simmonds, Peter

doi:10.1099/0022-1317-76-10-2493

Cited by 241 publications

(223 citation statements)

References 42 publications

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“…Genetic variants of HCV are known to be widely spread around the world. Genotypes 1, 2 and 3 are found on all continents, but in some geographical areas, such as Africa and Southeast Asia, viral isolates are highly divergent and particular genotypes or subtypes are predominant (13)(14)(15)(16). These data suggest the existence of a long-term endemic infection in these areas and some investigators have hypothesized that HCV might have originated in such places (17).…”

Section: Discussionmentioning

confidence: 88%

Geographic distribution of hepatitis C virus genotypes in Brazil

Campiotto

Pinho

Carrilho

et al. 2005

Braz J Med Biol Res

174

102

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Brazil is a country of continental dimension with a population of different ethnic backgrounds. Thus, a wide variation in the frequencies of hepatitis C virus (HCV) genotypes is expected to occur. To address this point, 1,688 sequential samples from chronic HCV patients were analyzed. HCV-RNA was amplified by the RT-PCR from blood samples collected from 1995 to 2000 at different laboratories located in different cities from all Brazilian States. Samples were collected in tubes containing a gel separator, centrifuged in the site of collection and sent by express mail in a refrigerated container to Laboratório Bioquímico Jardim Paulista, São Paulo, SP, Brazil. HCV-RNA was extracted from serum and submitted to RT and nested PCR using standard procedures. Nested PCR products were submitted to cycle sequencing reactions without prior purification. Sequences were analyzed for genotype determination and the following frequencies were found: 64.9% (1,095) for genotype 1, 4.6% (78) for genotype 2, 30.2% (510) for genotype 3, 0.2% (3) for genotype 4, and 0.1% (2) for genotype 5. The frequencies of HCV genotypes were statistically different among Brazilian regions (P = 0.00017). In all regions, genotype 1 was the most frequent (51.7 to 74.1%), reaching the highest value in the North; genotype 2 was more prevalent in the Center-West region (11.4%), especially in Mato Grosso State (25.8%), while genotype 3 was more common in the South (43.2%). Genotypes 4 and 5 were rarely found and only in the Southeast, in São Paulo State. The present data indicate the need for careful epidemiological surveys throughout Brazil since knowing the frequency and distribution of the genotypes would provide key information for understanding the spread of HCV.

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Section: Discussionmentioning

confidence: 88%

Geographic distribution of hepatitis C virus genotypes in Brazil

Campiotto

Pinho

Carrilho

et al. 2005

Braz J Med Biol Res

174

102

View full text Add to dashboard Cite

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“…The efficacy of IFN treatment within a six-month course was poor in patients with HCV-genotype lb and a high level of serum HCVRNAof more than 1 mEq/ml. But genotype lb is the predominant genotype in Japan (17) and in manyEuropean (19) and Western countries (20), so a pressing need exists to develop an effective antiviral strategy against this genotype. Kasahara et al (7) reported that the therapeutic efficacy was found to increase with a high total dose of IFN and prolonged IFN.…”

Section: Resultsmentioning

confidence: 99%

Efficacy and Changes of the Nonstructural 5A GENE by Prolonged Interferon Therapy for Patients with Hepatitis C Virus genotype 1b and a High Level of Serum HCV-RNA.

et al. 1999

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Object: The aim of this study was to examine the efficacy and the changes of amino acid sequences of the interferon sensitivity-determining region (ISDR) by prolonged interferon (IFN) treatment in patients who have serum hepatitis C virus (HCV)-genotype lb and a high level of serum HCV-RNA. Methods: Inclusion criteria were biopsy-proven chronic hepatitis, positive HCV-RNA,and an abnormal serum aminotransferase level. Twenty-five patients received 6 MU of natural IFN-oc daily for 8 weeks, followed by three times weekly for 40 weeks (1,056 MU). One patient was withdrawn from the study due to IFN side effects. Therefore, the remaining 24 patients (group 1) were studied the efficacy of IFN administration and changes of ISDR. As a control, 22 patients (group 2) treated with natural IFN-a for 24 weeks for the same period were studied retrospectively.Patients were defined as complete responders (CR) if serum HCV-RNA levels were negative for 6 months after IFN therapy. Results: According to this criterion, CR was 25% (6/24) in group 1 and 9.1% (2/22) in group 2. The normalization rates of alanine aminotransferease (ALT) for six months after termination of IFN was 41 % (10/24) in group 1 and 18.2% (4/22) in group 2. Regarding the changes of ISDR in patients with no CR, the change rates ofISDR were 16.7% (3/18) in group 1 and 10% (2/20) in group 2. Conclusion: We concluded that prolonged IFN therapy was effective for patients with HCV-genotype lb and a high level of serum HCV-RNA. (Internal Medicine 38: 461-466, 1999)

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“…Samples were tested for HCV RNA using nested polymerase chain reaction amplification of the NS5B (non-structural protein 5B) region, which provides a product suitable for differentiating different lineages of HCV infection. 72 …”

Section: Methodsmentioning

confidence: 99%

Assessing the impact and cost-effectiveness of needle and syringe provision and opioid substitution therapy on hepatitis C transmission among people who inject drugs in the UK: an analysis of pooled data sets and economic modelling

et al. 2017

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Background There is limited evidence of the impact of needle and syringe programmes (NSPs) and opioid substitution therapy (OST) on hepatitis C virus (HCV) incidence among people who inject drugs (PWID), nor have there been any economic evaluations. Objective(s) To measure (1) the impact of NSP and OST, (2) changes in the extent of provision of both interventions, and (3) costs and cost-effectiveness of NSPs on HCV infection transmission. Design We conducted (1) a systematic review; (2) an analysis of existing data sets, including collating costs of NSPs; and (3) a dynamic deterministic model to estimate the impact of differing OST/NSP intervention coverage levels for reducing HCV infection prevalence, incidence and disease burden, and incremental cost-effectiveness ratios to measure the cost-effectiveness of current NSP provision versus no provision. Setting Cost-effectiveness analysis and impact modelling in three UK sites. The pooled analysis drew on data from the UK and Australia. The review was international. Participants PWID. Interventions NSP coverage (proportion of injections covered by clean needles) and OST. Outcome New cases of HCV infection. Results The review suggested that OST reduced the risk of HCV infection acquisition by 50% [rate ratio (RR) 0.50, 95% confidence interval (CI) 0.40 to 0.63]. Weaker evidence was found in areas of high (≥ 100%) NSP coverage (RR 0.77, 95% CI 0.38 to 1.54) internationally. There was moderate evidence for combined high coverage of NSPs and OST (RR 0.29, 95% CI 0.13 to 0.65). The pooled analysis showed that combined high coverage of NSPs and OST reduced the risk of HCV infection acquisition by 29–71% compared with those on minimal harm reduction (no OST, ≤ 100% NSP coverage). NSPs are likely to be cost-effective and are cost-saving in some settings. The impact modelling suggest that removing OST (current coverage 81%) and NSPs (coverage 54%) in one site would increase HCV infection incidence by 329% [95% credible interval (CrI) 110% to 953%] in 2031 and at least double (132% increase; 95% CrI 51% to 306%) the number of new infections over 15 years. Increasing NSP coverage to 80% has the largest impact in the site with the lowest current NSP coverage (35%), resulting in a 27% (95% CrI 7% to 43%) decrease in new infections and 41% (95% CrI 11% to 72%) decrease in incidence by 2031 compared with 2016. Addressing homelessness and reducing the harm associated with the injection of crack cocaine could avert approximately 60% of HCV infections over the next 15 years. Limitations Findings are limited by the misclassification of NSP coverage and the simplified intervention definition that fails to capture the integrated services that address other social and health needs as part of this. Conclusions There is moderate evidence of the effectiveness of OST and NSPs, especially in combination, on HCV infection acquisition risk. Policies to ensure that NSPs can be accessed alongside OST are needed. NSPs are cost-saving in some sites and cost-effective in others. NSPs and OST are likely to prevent considerable rates of HCV infection in the UK. Increasing NSP coverage will have most impact in settings with low coverage. Scaling up other interventions such as HCV infection treatment are needed to decrease epidemics to low levels in higher prevalence settings. Future work To understand the mechanisms through which NSPs and OST achieve their effect and the optimum contexts to support implementation. Funding The National Institute for Health Research Public Health Research programme.

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Investigation of the pattern of hepatitis C virus sequence diversity in different geographical regions: implications for virus classification

Cited by 241 publications

References 42 publications

Geographic distribution of hepatitis C virus genotypes in Brazil

Geographic distribution of hepatitis C virus genotypes in Brazil

Efficacy and Changes of the Nonstructural 5A GENE by Prolonged Interferon Therapy for Patients with Hepatitis C Virus genotype 1b and a High Level of Serum HCV-RNA.

Assessing the impact and cost-effectiveness of needle and syringe provision and opioid substitution therapy on hepatitis C transmission among people who inject drugs in the UK: an analysis of pooled data sets and economic modelling

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