Purpose: Rapid severe acute respiratory syndrome coronavirus 2 test kits are crucial for bridging diagnostic gaps in health facilities and community screening mainly in resource limited settings. However, there is no objective evidence on their diagnostic performance. Thus, the study aimed to evaluate comparative diagnostic performance of three selected SARS-CoV-2 IgG/IgM rapid test kits in Ethiopia.
Methods: A cross-sectional study was conducted among 200 clients between May and July 2020 in Addis Ababa, Ethiopia. The performance of three SARS-CoV-2 rapid test kits EGENE, CTK BIOTECKs Onsite, and ACON Biotech were evaluated using blood specimens against RT-PCR on respiratory swabs. Sensitivity, specificity, and agreement with each other and to RT-PCR were computed using Vassarstats, MedCalc and SPSS version 23 statistical software.
Results: Test kits showed a heterogeneous comparative diagnostic performance in their sensitivity and specificity. The sensitivity was 61.18% (95% CI: 49.96-71.37%), 74.12% (95% CI: 63.28-82.74%) and 83.53% (95% CI: 73.57-90.38%) for kit A, B and C, respectively. Similarly, the specificity was 96.52% (90.81-98.88%), 94.78% (88.52-97.86%) and 94.78% (88.52-97.86%) for test kit A, B and C, respectively. The test kits have an agreement with RT-PCR with kappa value of 0.60 (0.48-0.83), 0.71 (0.65-0.93), and 0.80 (0.76-1.04) for A, B, and C, respectively. There was a significant difference on diagnostic performance among the three test kits and PCR with a p-value < 0.001 Cochran's Q test.
Conclusion: The diagnostic performance of the test kits was promising and recommended for COVID-19 diagnostics in combination with RT-PCR to detect more infected patients. It allows determining the seroprevalence of the virus and true extent of SARS-COV-2 community spread in resource limited settings. We underline countries to evaluate rapid diagnostic test kits before diagnostic use.
Keywords: COVID-19; Ethiopia; diagnostic performance; rapid test; sensitivity; specificity.
© 2021 Sisay et al.