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Can anyone order KnowNowᵀᴹ Tests?

At the moment, KnowNowᵀᴹ Tests are for professional use only, meaning that they need to be administered by a trained healthcare professional. This means that we can take orders from organisations that have in-house or outsourced healthcare professionals who can perform the tests, or testing service providers.

However, since the KnowNowᵀᴹ Test needs just a saliva sample, it is much easier to administer effectively than other similar tests, and still return highly sensitive results. So we are investigating whether specially-trained, competent individuals could be approved to administer KnowNow tests as well.

We are also in the process of trialling and seeking approval for a variation of the KnowNow test which could be administered by individuals themselves.

How big is a KnowNowᵀᴹ Test kit?

One box contains 25 tests, and measures 20cm (L) x 21cm (W) x 8cm (H).

How accurate are your tests?

COVID-19 test accuracy is typically determined by ‘specificity’ and ‘sensitivity’.

Specificity is about the extent to which you can eliminate false positives; sensitivity is how much virus needs to be present before a test picks it up. So there is always a need to strike a balance, when testing, between trying to pick up the virus as early as possible, versus accidentally delivering a positive test result for someone who is not actually infected.

The specificity of the KnowNowᵀᴹ Test is 100%. In more than 700 negative patient saliva samples, we haven’t had a single false positive.

What’s important when it comes to sensitivity is how much virus needs to be present in the patient sample for the test to give a positive signal. This is known as the 'Limit of Detection', and we measure this rather than clinical sensitivity as it is much more informative. Our Limit of Detection is between 50,000 and 200,000 viral copies per mL, making our test more sensitive than other rapid antigen tests available. The Abbott BinaxNow test, for example, needs 1,000,000 viral copies per mL in order to get a positive signal. The KnowNowᵀᴹ Test's very low Limit of Detection means it can detect infected people as early as day 3 to 4 of infection. This is before they become highly infectious, and a day or two earlier than most tests available (based on models of viral load in disease progression).

If you'd like to read more about this subject, we recommend this paper. It argues that the "Limit of Detection matters and directly impacts efforts to identify, control, and contain outbreaks during this pandemic" since "higher LoD are likely to miss nonnegligible fractions of infected individuals." It also makes the case that Limit of Detection values for tests using universal standard metrics should be readily available in the public domain to enable like-for-like comparison.

I've already activated my sample pack

If you have already activated your sample pack please go to the activation link that we emailed to you. Alternatively, if you fill in your email again we will re-send the activation link to you.

How long does a negative test result last for?

Receiving a negative result means that the individual tested does not have any live virus in the sample provided and is not currently infectious to others. However, it's important to be aware that they could still be exposed to the SARS-CoV-2 virus following the test. It could also be possible that the individual tested has already been exposed to the virus 1 or 2 days ago, and they have not yet become infectious to others.

As a result, we recommend that individuals are tested as regularly as possible to keep workplaces and communities safe. Depending on the scenario, we would recommend testing is repeated every 1 to 3 days.

When do you recommend tests are performed?

We recommend that tests are performed at the earliest opportunity possible, to ensure that individuals in the workplace, venue or community don't come into contact with each other prior to testing.

There's no particular time of day that's best to perform a test. Although it is important that individuals haven't had anything to eat or drink, and haven't smoked, within the 30 minutes prior to taking the test.

Is it necessary to perform multiple tests to be sure of the result?

It should not be necessary to perform more than one test on a given individual at a single point in time, unless the KnowNowᵀᴹ device test results window displays no lines at all, meaning that the test has failed, or unless it was not possible to read the test results within 15 to 60 minutes of applying the mixed saliva and buffer solution to the KnowNowᵀᴹ device.

However, receiving a negative result does not mean that the individual tested can't be exposed to the SARS-CoV-2 virus following the test. So we do recommend that individuals are tested regularly to keep workplaces and communities safe. Depending on the scenario, we would recommend testing is repeated every 1 to 3 days.

How does KnowNowᵀᴹ compare to COVID-19 PCR tests?

KnowNowᵀᴹ offers two key benefits over polymerase chain reaction (PCR) tests.

The first benefit is that the KnowNowᵀᴹ test needs only a saliva sample, which can be taken easily and comfortably from the mouth. PCR tests usually need a nasopharyngeal, anterior nasal or tonsil sample, all of which are painful and unpleasant for the individual being tested and more challenging to collect effectively for the clinical professional administering the test. No one wants to be made to cry or gag, or make someone else cry or gag, on a regular basis!

The second benefit is that the KnowNow test uses its unique detection mechanism to determine whether an individual is actually infectious, whereas PCR tests identify whether SARS-CoV-2 viral matter is present in an individual's body, regardless of whether it is already inactive.

Although PCR tests have been seen as the "gold standard" test for the SARS-CoV-2 virus, they do have a number of drawbacks. Laboratory processing is required, meaning that there is a delay before results can be returned, and the associated costs are relatively high. Also the detection mechanism does not specifically identify whether individuals are infectious. In fact, PCR tests detect the virus long after the infectious period, and individuals can continue to test positive for a mean of 17 days after they have stopped being able to infect others (source). This means that people who are not infectious are unnecessarily quarantined as a result of a positive PCR test.

Are there any health risks to or side effects from taking the KnowNowᵀᴹ Test?ᵀ

There are no health risks associated with using the KnowNow test itself, and it is safe to use on all individuals.

Receiving a negative result means that the individual tested does not have any live virus in the sample provided and is not currently infectious to others. However, it's important to be aware that they could still be exposed to the SARS-CoV-2 virus following the test. It could also be possible that the individual tested has already been exposed to the virus 1 or 2 days ago, and they have not yet become infectious to others.

As a result, we recommend that individuals are tested as regularly as possible to keep workplaces and communities safe. Depending on the scenario, we would recommend testing is repeated every 1 to 3 days.

If this regular testing is combined with mask wearing, hand washing and social distancing, the risk of virus transmission is vastly decreased.

How should KnowNowᵀᴹ tests be stored?

KnowNowᵀᴹ Tests should be stored between 2 and 30 degrees celsius, which means it's fine to store it at room temperature in the UK's mild climate.

There's no need to store it inside a fridge, unless you're expecting extremely hot weather. If you do choose to refrigerate the test though, just make sure it comes to room temperature before using it.

The KnowNowᵀᴹ Test device should also be stored still sealed in its foil pouch. Once removed from the foil pouch, it should be used within one hour.

Who makes the KnowNow Test?

The KnowNowᵀᴹ Test has been invented, developed and manufactured in the UK by Senseutics Limited, trading as Vatic.

Had COVID - 19 symptoms in the last 2 days? Apply here to help us make testing accessible to all.