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When did you start?

Vatic was founded in October 2019 by Alex Sheppard and Dr. Mona Kab Omir.

When the first wave of COVID-19 started in the UK in early 2020, our team immediately saw an opportunity to contribute to global efforts to tackle the pandemic, and leveraged work already underway on antigen testing to quickly start developing the KnowNowᵀᴹ Test.

Why do you need my company email to activate my sample pack?

So that we adhere to the strict rules around lateral flow tests, we have to make sure that anyone activating a sample pack is doing so purely to learn more about KnowNow Testing, and not as means of administering a clinical test.

What is SARS-CoV-2?

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the name given by the International Committee on Taxonomy of Viruses (ICTV) to the virus responsible for causing the disease, COVID-19.

We have a vaccine now, do we need testing anymore?

Although vaccine rollout is progressing extremely quickly in the UK, the government expects that it will be the end of July 2021 before every adult in the UK has been offered their first dose of a COVID-19 vaccine. Second doses should be received around 12 weeks after the first, and so it is likely to be the end of October 2021 before every adult has received both doses.

In the meantime, whilst we await full vaccine rollout, regular rapid antigen testing offers a way to enable the re-opening of society.

Beyond this, it is also important to consider that no vaccine is 100% effective even after 2 doses, that not everyone will accept or be able to have the vaccine, and that there is uncertainty as to whether the vaccines will work effectively against current or future mutations of the virus. We should also consider the fact that the UK is very much ahead of other countries around the world in progressing its vaccine rollout, and that it will still be some time before the vast majority of people globally will be vaccinated.

With these factors in mind, regular testing is likely to play a role in keeping societies safe and open for some time to come.

How long can unused KnowNowᵀᴹ Tests be kept before they expire?

The expiry date of KnowNowᵀᴹ Tests will be clearly marked on their packaging, and you can expect the shelf-life of each box of tests to be at least four months.

Why test people who don't have symptoms?

SARS-CoV-2 is able to spread from individuals who are pre-symptomatic or asymptomatic. As a result, testing and isolation based on symptoms alone will not be sufficient to stop the spread.

This narrative review of 16 clinical studies around the globe concludes that between 40-45% of those infected with SARS-CoV-2 never develop symptoms, and that these asymptomatic carriers can infect others for an extended period, perhaps longer than 14 days.

Regular community testing with a rapid antigen test like the KnowNowᵀᴹ Test to identify asymptomatic, but infectious, individuals offers one way to break the chain of transmission and enable the re-opening of societies.

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.

How should used KnowNowᵀᴹ Tests be disposed of?

Used tests, swabs and buffer dropper tubes should be disposed of as potentially hazardous clinical waste.

How frequently should employees or visitors be tested?

We recommend that individuals are tested as regularly as possible to keep workplaces, venues and communities safe.

It is important to remember that individuals can still go on to be exposed to the virus following a negative test result. Additionally, a high proportion of infectious people show no symptoms at all, and so regular testing is key to breaking the chain of transmission.

Depending on the scenario, we would recommend that testing is performed every 2-3 days, or daily, depending on the scenario.

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.

What is the limit of detection of the KnowNowᵀᴹ Test?

The Limit of Detection (LoD) is the smallest amount of virus in a sample that a given device can consistently detect.

The Liverpool School of Tropical Medicine carried out an analytical study of the KnowNowᵀᴹ test, which determined that the LoD is 500 plaque-forming units per millilitre (PFU/ml). Based on accepted models of viral load in disease progression, this very low LoD suggests that the KnowNow test 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.

In the absence of a single study that compares the LoD of KnowNowᵀᴹ to that of other tests, it is not possible to do a like-for-like comparison of the LoDs of different lateral flow tests determined by different studies. This is because there wouldn't be parity across cell cultures and strains of the virus used in the different studies. Additionally, it's important to consider that what the KnowNowᵀᴹ test detects is fundamentally different from other tests. KnowNowᵀᴹ is a true infectivity test which looks exclusively for the spike protein only present on active SARS-CoV-2 viruses. Whereas other lateral flow tests detect the nucleocapsid protein encapsulated in the centre of the virus, which can be present whether the virus is active or not.

The PFU/ml measure, as used in the Liverpool School of Tropical Medicine KnowNowᵀᴹ analytical study, is a measure of only the number of virus particles capable of forming plaques in a given sample - viral particles that are defective or which fail to infect their target cell will not produce a plaque and so are not counted by this measure. No inference can be made about the relationship of PFU to the overall number of viral particles in the sample, since this will differ from sample to sample.

Since the KnowNow test specifically detects infectious viral particles only, an LoD measured in PFU/ml is an informative and appropriate measure. However, for other lateral flow tests which indiscriminately detect active and inactive viral particles, an LoD referencing PFU/ml is not particularly informative or comparable to the KnowNowᵀᴹ LoD. For example, the sample used to determine LoD may have had a very low PFU/ml, but many inactive viral particles which were detected by the test. Ultimately, other lateral flow tests are not true tests for COVID infectivity, they do not detect only infectious virus like the KnowNowᵀᴹ test does.

If you'd like to read more about this subject, we recommend reading 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 LoD values for tests should be benchmarked against a universal standard and readily available in the public domain to enable like-for-like comparison of SARS-CoV-2 detection methods.

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