To help battle the COVID pandemic and identify potentially infected individuals, Antwerp Dental Group staff will each undertake a ‘lateral-flow test’ twice per week. Not all lateral flow tests are the same. Some require a swabbing of the nose and throat (as described in the video), and others such as the Innova Lateral flow test require you to swab ONLY the inside of the nose. You must follow the instructions supplied with the kit you are using!
This test involves swabbing the inside of the nose carefully and dipping the swab into an extraction medium. This extraction medium will suspend viral antigens in solution and be maintained in a dropper bottle. You will place a couple of droplets onto a lateral flow strip and capillary flow of the analyte will draw this fluid across the strip to the ‘T’ line which consists of antibodies to Covid-19 proteins, and a control line which consists of alpha IgG antibodies.
The strip consists of a nitrocellulose membrane which enables the lateral flow assay. This is a ‘rapid test’, and a result will be identified in 30 minutes. After the 30 minutes a ‘T’ line (Test line) and a ‘C’ line (Control line) is assessed. Appearance of the C line confirms the validity of the test :
Lateral flow assays should only be performed in asymptomatic individuals. Symptomatic persons should self isolate and eventually receive a RT-PCR test which has a high effectiveness (sensitivity and specificity).
It is entirely possible to attain a ‘false-positive’, and a ‘false-negative’ test result with a lateral flow assay.
Lateral flow tests have been widely dismissed as not being very accurate and have ‘loosely’ been identified as being 58% effective. What does this mean ?
Lateral flow tests :
Lateral flow tests therefore have tremendous value in keeping COVID negative staff at work and supporting essential health services.
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