Short communication
Handling and accuracy of four rapid antigen tests for the diagnosis of SARS-CoV-2 compared to RT-qPCR

https://doi.org/10.1016/j.jcv.2021.104782Get rights and content

Highlights

  • Four rapid antigen tests showed moderate sensitivity (< = 55 %) for SARS-CoV-2.

  • All tests were able to detect high infectious samples with high reliability (95 %).

  • Handling of all the assays poses to users to significant risk for contamination.

Abstract

Background

SARS-CoV-2 molecular diagnostics is facing material shortages and long turnaround times due to exponential increase of testing demand.

Objective

We evaluated the analytic performance and handling of four rapid Antigen Point of Care Tests (AgPOCTs) I-IV (Distributors: (I) Roche, (II) Abbott, (III) MEDsan and (IV) Siemens).

Methods

100 RT-PCR negative and 84 RT-PCR positive oropharyngeal swabs were prospectively collected and used to determine performance and accuracy of these AgPOCTs. Handling was evaluated by 10 healthcare workers/users through a questionnaire.

Results

The median duration from symptom onset to sampling was 6 days (IQR 2–12 days). The overall respective sensitivity were 49.4 % (CI95 %: 38.9–59.9), 44.6 % (CI95 %: 34.3–55.3), 45.8 % (CI95 %: 35.5–56.5) and 54.9 % (CI95 %: 43.4−65.9) for tests I, II, III and IV, respectively. In the high viral load subgroup (containing >106 copies of SARS-CoV-2 /swab, n = 26), AgPOCTs reached sensitivities of 92.3 % or more (range 92.3 %–100 %). Specificity was 100 % for tests I, II (CI95 %: 96.3–100 for both tests) and IV (CI95 %: 96.3–100) and 97 % (CI95 %: 91.5–98.9) for test III. Regarding handling, test I obtained the overall highest scores, while test II was considered to have the most convenient components. Of note, users considered all assays, with the exception of test I, to pose a significant risk for contamination by drips or spills.

Discussion

Besides some differences in sensitivity and handling, all four AgPOCTs showed acceptable performance in high viral load samples. However, due to the significantly lower sensitivity compared to RT-qPCR, a careful consideration of pro and cons of AgPOCT has to be taken into account before clinical implementation.

Abbreviations

RT-qPCR
Reverse transcription-polymerase chain reaction, AgPOCT

Keywords

Accuracy
Handling
SARS-CoV-2
Rapid antigen test AgPOCT

Cited by (0)

1

Shared co-first/ co-last authorship.

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