9 research outputs found
Point-of-care screening for a current Hepatitis C virus infection: influence on uptake of a concomitant offer of HIV screening
Eliminating hepatitis C as a public health threat requires an improved understanding of how to increase testing uptake. We piloted point-of-care testing (POCT) for a current HCV infection in an inner-city Emergency Department (ED) and assessed the influence on uptake of offering concomitant screening for HIV. Over four months, all adults attending ED with minor injuries were first invited to complete an anonymous questionnaire then invited to test in alternating cycles offering HCV POCT or HCV+HIV POCT. Viral RNA was detected in finger-prick blood by GeneXpert. 814/859 (94.8%) questionnaires were returned and 324/814 (39.8%) tests were accepted, comprising 211 HCV tests and 113 HCV+HIV tests. Offering concomitant HIV screening reduced uptake after adjusting for age and previous HCV testing (odds ratio 0.51; 95% confidence interval [CI] 0.38–0.68; p < 0.001). HCV prevalence was 1/324 (0.31%; 95% CI 0.05–1.73); no participant tested positive for HIV. 167/297 (56.2%) POCT participants lived in the most deprived neighbourhoods in England. HCV RNA testing using finger-prick blood was technically feasible. Uptake was moderate and the offer of concomitant HIV screening showed a detrimental impact on acceptability in this low prevalence population. The findings should be confirmed in a variety of other community settings
Interferon λ 3 and 4 genotyping using high-resolution melt curve analysis suitable for multiple clinical sample types
Many people living with hepatitis C virus (HCV) infection will continue to rely on interferon-based regimens until effective strategies to minimize the cost of directly acting antivirals (DAAs) and to improve treatment access are implemented. Host single-nucleotide polymorphisms related to IFNL3 and IFNL4 are associated with spontaneous clearance of HCV, and pegylated interferon- and DAA-based treatment outcomes. We describe a simple and rapid genotyping method for IFNL rs12979860, rs8099917, and rs368234815 using high-resolution melting analysis for DNA extracted from whole blood, buffy coat, plasma, serum, and dried blood spots. This assay successfully detected all three polymorphisms on DNA extracted by the automated platform easyMAG from all samples when compared to sequenced amplicons. Analysis of 126 participants with recent HCV infection from the Australian Trial in Acute Hepatitis C study demonstrated the prevalence of favorable single-nucleotide polymorphisms were 62%, 51%, and 45% for rs8099917 TT, rs12979860 CC, and rs368234815 TT/TT, respectively. The genotyping assay described here provides a rapid and affordable IFNL3 and IFNL4 genotyping method for a range of clinical sample types. Until global access to DAAs is achieved, IFNL3 and IFNL4 genotyping could identify those likely to clear naturally and in whom treatment could be delayed, or help prioritize DAA treatment to those less likely to respond to interferon-containing regimens
The influence of hepatitis C virus genetic region on phylogenetic clustering analysis
Sequencing is important for understanding the molecular epidemiology and viral evolution of hepatitis C virus (HCV) infection. To date, there is little standardisation among sequencing protocols, in-part due to the high genetic diversity that is observed within HCV. This study aimed to develop a novel, practical sequencing protocol that covered both conserved and variable regions of the viral genome and assess the influence of each subregion, sequence concatenation and unrelated reference sequences on phylogenetic clustering analysis. The Core to the hypervariable region 1 (HVR1) of envelope-2 (E2) and non-structural- 5B (NS5B) regions of the HCV genome were amplified and sequenced from participants from the Australian Trial in Acute Hepatitis C (ATAHC), a prospective study of the natural history and treatment of recent HCV infection. Phylogenetic trees were constructed using a general time-reversible substitution model and sensitivity analyses were completed for every subregion. Pairwise distance, genetic distance and bootstrap support were computed to assess the impact of HCV region on clustering results as measured by the identification and percentage of participants falling within all clusters, cluster size, average patristic distance, and bootstrap value. The Robinson-Foulds metrics was also used to compare phylogenetic trees among the different HCV regions. Our results demonstrated that the genomic region of HCV analysed influenced phylogenetic tree topology and clustering results. The HCV Core region alone was not suitable for clustering analysis; NS5B concatenation, the inclusion of reference sequences and removal of HVR1 all influenced clustering outcome. The Core-E2 region, which represented the highest genetic diversity and longest sequence length in this study, provides an ideal method for clustering analysis to address a range of molecular epidemiological questions. Copyright
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A molecular transmission network of recent hepatitis C infection in people with and without HIV: Implications for targeted treatment strategies
Combining phylogenetic and network methodologies has the potential to better inform targeted interventions to prevent and treat infectious diseases. This study reconstructed a molecular transmission network for people with recent hepatitis C virus (HCV) infection and modelled the impact of targeting directly acting antiviral (DAA) treatment for HCV in the network. Participants were selected from three Australian studies of recent HCV from 2004 to 2014. HCV sequence data (Core-E2) from participants at the time of recent HCV detection were analysed to infer a network by connecting pairs of sequences whose divergence was ≤.03 substitutions/site. Logistic regression was used to identify factors associated with connectivity. Impact of targeting HCV DAAs at both HIV co-infected and random nodes was simulated (1 million replicates). Among 236 participants, 21% (n=49) were connected in the network. HCV/HIV co-infected participants (47%) were more likely to be connected compared to HCV mono-infected participants (16%) (OR 4.56; 95% CI; 2.13-9.74). Simulations targeting DAA HCV treatment to HCV/HIV co-infected individuals prevented 2.5 times more onward infections than providing DAAs to randomly selected individuals. Results demonstrate that genetic distance-based network analyses can be used to identify characteristics associated with HCV transmission, informing targeted prevention and treatment strategies
HIV infection and hepatitis C virus genotype 1a are associated with phylogenetic clustering among people with recently acquired hepatitis C virus infection
The aim of this study was to identify factors associated with phylogenetic clustering among people with recently acquired hepatitis C virus (HCV) infection. Participants with available sample at time of HCV detection were selected from three studies; the Australian Trial in Acute Hepatitis C, the Hepatitis C Incidence and Transmission Study - Prison and Community. HCV RNA was extracted and Core to E2 region of HCV sequenced. Clusters were identified from maximum likelihood trees with 1000 bootstrap replicates using 90% bootstrap and 5% genetic distance threshold. Among 225 participants with available Core-E2 sequence (ATAHC, n=113; HITS-p, n. = 90; and HITS-c, n=22), HCV genotype prevalence was: G1a: 38% (n=86), G1b: 5% (n=12), G2a: 1% (n=2), G2b: 5% (n=11), G3a: 48% (n=109), G6a: 1% (n=2) and G6l 1% (n=3). Of participants included in phylogenetic trees, 22% of participants were in a pair/cluster (G1a-35%, 30/85, mean maximum genetic distance. = 0.031; G3a-11%, 12/106, mean maximum genetic distance =0.021; other genotypes-21%, 6/28, mean maximum genetic distance= 0.023). Among HCV/HIV co-infected participants, 50% (18/36) were in a pair/cluster, compared to 16% (30/183) with HCV mono-infection (P=<. 0.001). Factors independently associated with phylogenetic clustering were HIV co-infection [vs. HCV mono-infection; adjusted odds ratio (AOR) 4.24; 95%CI 1.91, 9.39], and HCV G1a infection (vs. other HCV genotypes; AOR 3.33, 95%CI 0.14, 0.61).HCV treatment and prevention strategies, including enhanced antiviral therapy, should be optimised. The impact of targeting of HCV treatment as prevention to populations with higher phylogenetic clustering, such as those with HIV co-infection, could be explored through mathematical modelling
Evaluation of the Xpert HCV Viral Load point-of-care assay from venepuncture-collected and finger-stick capillary whole-blood samples: a cohort study
Background Point-of-care hepatitis C virus (HCV) RNA testing offers an advantage over antibody testing (which only indicates previous exposure), enabling diagnosis of active infection in a single visit. In this study, we evaluated the performance of the Xpert HCV Viral Load assay with venepuncture and finger-stick capillary whole-blood samples. Methods Plasma and finger-stick capillary whole-blood samples were collected from participants in an observational cohort enrolled at five sites in Australia (three drug and alcohol clinics, one homelessness service, and one needle and syringe programme). We compared the sensitivity and specificity of the Xpert HCV Viral Load test for HCV RNA detection by venepuncture and finger-stick collection with the Abbott RealTime HCV Viral Load assay (gold standard). Findings Of 210 participants enrolled between Feb 8, 2016, and July 27, 2016, 150 participants had viral load testing results for the three assays tested. HCV RNA was detected in 45 (30% [95% CI 23–38]) of 150 participants based on Abbott RealTime. Sensitivity of the Xpert HCV Viral Load assay for HCV RNA detection in plasma collected by venepuncture was 100·0% (95% CI 92·0–100·0) and specificity was 99·1% (95% CI 94·9–100·0). Sensitivity of the Xpert HCV Viral Load assay for HCV RNA detection in samples collected by finger-stick was 95·5% (95% CI 84·5–99·4) and specificity was 98·1% (95% CI 93·4–99·8). No adverse events caused by the index test or the reference standard were observed. Implications The Xpert HCV Viral Load test can detect active infection from a finger-stick sample, which represents an advance over antibody-based tests that only indicate past or previous exposure. Funding National Health and Medical Research Council (Australia), Cepheid, South Eastern Sydney Local Health District (Australia), and Merck Sharp & Dohme (Australia)
Acceptability and preferences of point-of-care finger-stick whole-blood and venepuncture hepatitis C virus testing among people who inject drugs in Australia
Background: Uptake of hepatitis C virus (HCV) testing remains inadequate globally. Simplified point-of-care tests should enhance HCV diagnosis and elimination. We aimed to assess the acceptability of finger-stick and venepuncture HCV RNA testing among people who inject drugs (PWID). Methods: Participants were enrolled in an observational cohort study with recruitment at 13 sites between June 2016 and February 2018. Capillary whole-blood collected by finger-stick and plasma collected by venepuncture were performed for Xpert ® HCV viral load testing. Participants completed a questionnaire on acceptability of, and preferences for, blood collection methods. Results: Among 565 participants (mean age, 44 years; 69% male), 64% reported injecting drugs in the last month, and 63% were receiving opioid substitution treatment. Eighty three percent reported that finger-stick testing was very acceptable. Overall, 65% of participants preferred finger-stick over venepuncture testing, with 61% of these preferring to receive results in 60 min. The most common reason for preferring finger-stick over venepuncture testing was it was quick (62%) followed by venous access difficulties (21%). The main reasons for preferring venepuncture over finger-stick testing were that it was quick (61%) and accurate (29%). Females were more likely to prefer finger-stick testing than males (adjusted OR 1.96; 95% CI 1.30, 2.99; p = 0.002). Among people with recent (previous month) injecting drug use, Aboriginal and/or Torres Strait Islander people were less likely than non-Aboriginal people to prefer finger-stick testing (adjusted OR 0.57; 95% CI 0.34, 0.9; p = 0.033). Conclusions: Finger-stick whole-blood collection is acceptable to people who inject drugs, with males and Aboriginal and/or Torres Strait Islander people with recent injecting drug use less likely to prefer finger-stick testing. Further research is needed to evaluate interventions integrating simplified point-of-care HCV testing to engage people in care in a single-visit, thereby facilitating HCV treatment scale-up