The COVID-19/Influenza A+B/RSV Antigen Combo Rapid Test Kit is based on the principle of a qualitative immunochromatographic assay for the determination of SARS-CoV-2, Influenza A/B and RSV from nasal swab and nasopharyngeal swab samples from patients.

Strip ‘COVID-19 Ag/RSV’ consists of a nitrocellulose membrane pre-coated with mouse anti-SARS-CoV-2 antibodies/anti-RSV antibody on the test line (T line) and with goat anti-mouse polyclonal antibodies on the control line (C line). The conjugate pad is sprayed with gold-labeled solution (mouse monoclonal antibodies anti-SARS-CoV-2/ anti-RSV). Strip ‘Flu A+B’ consists of a nitrocellulose membrane pre-coated with mouse anti-Influenza A antibodies on the ‘A’ line, mouse anti-Influenza B antibodies on the ‘B’ line and with goat anti-mouse polyclonal antibodies on the control line (C line). The conjugate pad is sprayed with gold-labeled solution (mouse monoclonal antibodies anti-influenza A and B)

If the sample is SARS-CoV-2/RSV positive, the antigens of the sample react with the gold-labeled anti-SARS-CoV-2 monoclonal antibodies/ anti-RSV antibody in the Strip ‘COVID-19 Ag/RSV’ which was previously pre-dried on the conjugate pad. The mixtures then captured on the membrane by the pre-coated SARS-CoV-2 monoclonal antibodies/RSV antibody and a red line will be visible in the strips indicating a positive result.

If the sample is Influenza A and/or B positive, the antigens of the sample react with the gold-labeled anti-Influenza A and/or monoclonal antibodies in the Strip ‘Flu A+B’, which were previously pre-dried on the conjugate pad. The mixtures then captured on the membrane by the pre-coated Influenza A and/or B monoclonal antibodies and a red line will be visible in their respective lines indicating a positive result.

If the sample is negative, there is no SARS-CoV-2 or RSV or Influenza A or Influenza B antigens presence or the antigens may be present in a concentration below the limit of detection (LoD) for which the the red lines will not appear. Whether the sample is positive or not, in the 3 strips, the C lines will always appear. The presence of these green lines serve as: 1) verification that sufficient volume is added, 2) that proper flow is obtained and 3) an internal control for the kit.