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• Diagnostic tests are used to detect active coronavirus infections and determine whether quarantine or isolation is needed.
• Antibody tests determine the long-term immune status of a previously-infected individual.

Real-time reverse transcription-polymerase chain reaction (RT-PCR) is a sensitive NAAT for diagnosing active SARS-CoV-2 infections. These tests are performed at laboratories, where trained technicians detect viral genetic material in human samples. First, RNA is extracted from a patient’s saliva or nasal swab. RNA is then reverse transcribed into cDNA by a reverse transcriptase enzyme and used as templates in PCR amplification. SARS-CoV-2 specific primers and probes have optimal sensitivity and specificity to the viral genetic sequence, allowing infections to be detected prior to symptom onset.

• Patient sample collection (Nasal, Nasopharyngeal, Oropharyngeal, Sputum, Saliva)
• RNA isolation from the patient sample.
• Testing of the isolated RNA using a commercial RT-qPCR Detection Kit (kits may include COVID-19 primers and probes, reverse transcriptase, DNA polymerase, nucleotides, nuclease-free H_{2O, and reaction buffer).}
• The COVID-19 primers and probes included in the detection kit target SARS-CoV-2 proteins such as Rdrp, N protein, Orf1ab, and E protein, (read our article on SARS-CoV-2 structure and infection cycle).
• The qPCR reaction is conducted via a thermocycler program that will heat and cool samples in a series of steps to carry out the denaturation, annealing, and elongation processes required to amplify and detect the target sequence.
• The patient’s sample is run alongside positive and negative controls to ensure the run’s setup was done correctly and no sample contamination occurred, which would lead to false negatives and positives respectively. Detection of SARS-CoV-2 RNA indicates an active infection.

abm’s GenomeCoV19 Detection Kit (Cat. No. G628.v2) is a ready-to-use RT-qPCR test that includes all test components needed to detect SARS-CoV-2 in less than 2 hours. Our kit is affordably priced at US$1.77/test and is both widely used in Europe under the CE-IVD certification.

Antigen tests are rapid immunoassays that detect viral protein in the patient’s nose or throat. Presence of SARS-CoV-2 nucleocapsid protein in nasopharyngeal and anterior nasal swab samples indicates an active infection. In comparison to RT-qPCR, immunoassay tests are cheaper, faster, and can be made available at a point of care location. Antigen tests are most effective at identifying the virus after symptoms have already developed, and may result in false negatives during early infections.

• Collect Nasopharyngeal and anterior nasal swabs from patient.
• Release viral antigens using a commercial extraction buffer.
• Apply sample extract to the disposable testing strip or testing cartridge.
• Set a timer and wait as the sample is absorbed into the strip by capillary action, until it reaches the antibodies and detector molecules.
• Interpret results based on manufacturer’s protocol.

• Extraction and transport of blood samples to a laboratory for testing.
• Isolate serum from blood samples.
• Coat the wells of an ELISA plate with antigens recognized specifically by human anti-SARS-CoV-2 IgG antibodies.
• Add blood serum to each well of the antigen coated plate.
• Add anti-IgG secondary antibodies that are labelled with an enzyme that enables signal detection with an automated plate reader and quantitative analysis.
• Incubate, then wash away unbound antibodies.
• Interpret data according to the manufacturer's protocol.

• Use a transfer pipet to transfer 1 drop of whole blood, plasma, or serum to the sample well.
• Add 2 to 3 drops of the kit’s buffer.
• Wait 10 minutes for test results, follow test kit instructions for results interpretation.