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  Antigen Test - Frequently Asked Questions  
  What are rapid tests?

Rapid tests are small, portable tests which use chromatographic technology to determine the contagiousness of a patient in a short period of time. The tests are composed of a small cassette which contains the filter paper, a small vial filled with buffer solution which doubles as a pipette, and a cotton bud. 

  How do rapid tests work?

They are administered via nasal or oral swab. The cotton bud is then placed in the small vial filled with buffer solution and left for around half a minute. After this time has elapsed, turn the vial upside-down and use the pipette attachment to squeeze the mixture onto the small circular opening located at the bottom of the cassette below the larger rectangular opening. Now, wait 15 minutes for the results. You will notice two letters beside the rectangular opening.

On the filter paper beside these letters, lines might or might not appear as the 15 minutes elapses. The most important of these letters is C, beside which a line must appear if the test has worked. If a line appears at C, take a look at T which, depending on your level of infection, may or may not display a line beside it after 15 minutes. If a fairly solid, distinct line appears at T, then you have tested positive for COVID-19 and are currently infectious.

If you prefer, watch this video for a walk-through of the test:  

  Are rapid tests reliable?

Yes, if you’re trying to find out if someone is infectious. The amount of viral material in your system - what is referred to as your ‘viral load’ - must exceed a certain threshold for you to be able to spread the virus to others. In short, you can be infected without being infectious.

So, unlike other tests which attempt to locate any and all traces of viral material generated by COVID-19, rapid tests only deliver a positive result if it detects the amounts in the patient which would make them contagious. For more information, take a look at our blog [] on the topic.  

  Who can administer a rapid test?

Anyone, including the patient themselves.

The test is extremely easy to perform, with very little margin for error. Each test comes with thorough, accessible instructions, too.  

  What is the difference between NHS COVID-19 tests and these?

The NHS uses a type of test known as a PCR test, or polymerase chain reaction test, which uses a technique that replicates the cells of the sample to create a larger picture of the patient’s infection status. This allows PCR testing to provide a more comprehensive set of results. The complicated nature of the process involved in PCR testing is a large part of the reason for the 48-hour waiting time.

While PCR tests can detect incredibly small amounts of viral material in the patient, rapid tests have been proven to deliver positive results if the patient is currently infectious. In other words, whilst PCR testing can tell you more, rapid testing lets you know about the most necessary information much faster.

What is the difference between antibody and antigen rapid tests?

An antibody test attempts to detect antibodies - specialised proteins which are capable of defending against and removing a virus. An antigen test looks for viral material - the traces of an active virus in the body. In practice, these differences amount to different perspectives on the life-cycle of the virus in a given patient. An antibody test will tell you whether you have had the virus (and potentially, how immune to it you have become). An antigen test tells you whether you currently have the virus.

For a more detailed discussion of these differences, check out our blog [].

For how long is the result from a rapid test valid?

For how long is the result from a rapid test valid? Due to sensitivity of a rapid test, it might be necessary to conduct a test once a day for a few days, especially if you are displaying symptoms.

That being said, you can rest assured that at least for a 24-hour period, the result from each individual test will hold.


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  Further Information

We realise that this is a new concept and is quite complex (scientific).
Therefore, we have created an easy-to-use ‘Resource Centre’ to help you get the detail you need via blogs, pdf’s and webpages on the site.

Please call or email our team if you have a specific request not covered below. We will be happy to help.




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