ABSTRACT
BACKGROUND: In England, over 80 % of those with hepatitis C virus (HCV) infection have injected drugs. We quantified the HCV cascade of care (CoC) among people who inject drugs (PWID) in England and determined whether this improved after direct-acting antivirals (DAAs) were introduced. METHODS: We analysed data from nine rounds of national annual cross-sectional surveys of PWID recruited from drug services (2011-2019; N = 12,320). Study rounds were grouped as: 'Pre-DAAs' (2011-2014), 'Prioritised DAAs' (2015-2016) and 'Unrestricted DAAs' (2017-2019). Participants were anonymously tested for HCV antibodies and RNA and completed a short survey. We assessed the proportion of PWID recently (current/previous year) tested for HCV. For participants ever HCV treatment eligible (past chronic infection with history of treatment or current chronic infection), we assessed the CoC as: HCV testing (ever), received a positive test result, seen a specialist nurse/doctor, and ever treated. We used logistic regression to determine if individuals progressed through the CoC differently depending on time-period, whether time-period was associated with recent testing (all participants) and lifetime HCV treatment (ever eligible participants), and predictors of HCV testing and treatment in the Unrestricted DAAs period. RESULTS: The proportion of ever HCV treatment eligible PWID reporting lifetime HCV treatment increased from 12.5 % in the Pre-DAAs period to 25.6 % in the Unrestricted DAAs period (aOR:2.40, 95 %CI:1.95-2.96). There were also increases in seeing a specialist nurse/doctor. The largest loss in the CoC was at treatment for all time periods. During the Unrestricted DAAs period, recent (past year) homelessness (vs never, aOR:0.66, 95 %CI:0.45-0.97), duration of injecting (≤3 years vs >3 years; aOR:0.26, 95 %CI:0.12-0.60), never (vs current, aOR:0.31, 95 %CI:0.13-0.75) or previously being prescribed OAT (vs current, aOR:0.67, 95 %CI:0.47-0.95), and never using a NSP (vs past year, aOR:0.27, 95 %CI:0.08-0.89) were negatively associated with lifetime HCV treatment. The proportion of PWID reporting recent HCV testing was higher during Unrestricted DAAs (56 %) compared to Pre-DAAs (48 %; aOR:1.28, 95 %CI:1.06-1.54). CONCLUSION: COC stages from seeing a specialist onwards improved after DAAs became widely available. Further improvements in HCV testing are needed to eliminate HCV in England.
ABSTRACT
The development of rapid, robust and high performance point-of-care diagnostics relies on the advancement and combination of various areas of research. We have developed an assay for the detection of multiple mRNA molecules that combines DNA nanotechnology with fluorescent nanomaterials. The core switching mechanism is toehold-mediated strand displacement. We have used fluorescent quantum dots (QDs) as signal transducers in this assay, as they bring many benefits including bright fluorescence and multiplexing abilities. The resulting assay is capable of multiplexed detection of long RNA targets against a high concentration of background non-target RNA, with high sensitivity and specificity and limits of detection in the nanomolar range using only a standard laboratory plate reader. We demonstrate the utility of our QD-based system for the detection of two genes selected from a microarray-derived tuberculosis-specific gene expression signature. Levels of up- and downregulated gene transcripts comprising this signature can be combined to give a disease risk score, making the signature more amenable for use as a diagnostic marker. Our QD-based approach to detect these transcripts could pave the way for novel diagnostic assays for tuberculosis.
