Theme: Epidemiology & Public Health Research Year: 2018
Background:
Innovative technologies provide opportunities for scaling-up HCV testing of PWID in resourceconstrained countries.
Approach:
Adopting a health sector perspective in Western Africa, a decision tree model was developed
for estimating the expected number of true positive (TP) HCV cases and associated costs of
12 testing strategies with the following characteristics: a single-step or two-step testing
sequence, HCV-RNA or HCV core antigen as confirmative biomarker, laboratory or point-ofcare (POC) tests, and serum samples or dried blood spots (DBS). Reference case assumed
a 38.9% seroprevalence as reported in PWID from Senegal, a 5% uptake for strategies
starting with a serum sample-based test (versus 30% for others), and a 90% loss to follow-up
rate among individuals tested HCV-Ab positive for strategies with second-step tests based on
serum samples.
Outcomes:
Compared to the cheapest strategy, i.e., HCV-Ab followed by HCV-cAg both based on serum
samples (strategy A), three strategies remained undominated: POC HCV-Ab followed by POC
HCV-RNA (strategy B), single-step POC HCV-RNA (strategy C) and POC HCV-Ab followed
by HCV-RNA on DBS (strategy D). The above-mentioned strategies identified 0.5%, 28.2%,
28.3 and 29.3% of HCV-infected PWID, respectively, with corresponding costs/individual
screened of 0.95€, 4.22€, 4.46€, and 11.44€, and corresponding costs/TP case of 750€, 55€,
57€ and 143€, respectively. Incremental cost-effectiveness ratios (€/additional TP case) were
the following: 43 (strategy B vs strategy A), 624 (C versus B) and 2748 (D versus C).
Whenever HCV seroprevalence reached 45%, sensitivity analysis showed that when
compared to strategy A, strategy C became more cost-effective than strategy B, but with a
higher rate of false positives (2 and 0.4/1000 PWID in strategy C and B, respectively). Results
were sensitive to screening uptake and loss to follow-up rates.
Conclusion:
Strategies B and C should be considered in priority for HCV screening of PWID living in
resource-constrained countries.
Disclosure of Interest Statement:
The authors have no conflict of interest to declare.