If there is one red line visible next to the "C" in the KnowNowᵀᴹ device test results window, and any line at all, no matter how faint, appears next to the "T", then the test result is positive. This indicates that the SARS-CoV-2 antigen has been detected in the sample.
Following a positive result, current government guidance on matters including self-isolation and reporting the result should be followed.
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.
Used tests, swabs and buffer dropper tubes should be disposed of as potentially hazardous clinical waste.
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.
To date we have conducted three clinical studies. The first was a UK Government-supported National Institute for Health Research (NIHR) study across ten UK hospitals; the second was with Liverpool School of Tropical Medicine, and the third is a community study that we have led ourselves. We have also carried out our own analytical assessments, as well as two Public Health England analytical assessments.
We have worked with over 280 negative patient samples and around 100 COVID-19 positive patients across our studies. We are also currently carrying out a 650+ patient clinical trial with sites in the UK, USA and Brazil to provide us with a higher volume of clinical data, and with a view to additional regulatory approvals to widen the reach of the impact we can have globally in pandemic recovery.
So that the KnowNowᵀᴹ Test is used as effectively as possible, it currently needs to be administered by a trained healthcare professional.
A trained healthcare professional is defined by the Medicines and Healthcare products Regulatory Agency (MHRA) in the Target Product Profile for Point of Care SARS-CoV-2 Detection Tests as a professional belonging to one of the 10 health and social care professional bodies that are overseen by the Professional Standards Authority. You can find a list of these professions here.
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 other 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 KnowNowᵀᴹ Test which could be administered by individuals themselves.
The KnowNowᵀᴹ Test is unique to other lateral flow antigen tests in 3 key areas.
The first key difference is that the KnowNow test needs only a saliva sample, which can be taken easily and comfortably from the mouth. Other lateral flow antigen 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 is that the KnowNowᵀᴹ Test looks specifically for live virus which would cause the individual tested to be able to infect others. Although other lateral flow antigen tests are often said to test whether an individual is infectious, this is because they have a higher Limit of Detection and can only detect the virus when there are more viral particles present in the sample. As a result, they offer a proxy measure for infectivity, rather than directly testing whether there is live virus in the sample. The KnowNowᵀᴹ Test on the other hand is a true infectiousness test, which uses a unique patented mechanism which detects a completely different part of the virus.
Finally, the KnowNowᵀᴹ Test is also more sensitive than other rapid antigen tests available, as it is able to pick up the presence of the virus even when there is much less of it present in the sample. Our Limit of Detection is between 50,000 and 200,000 viral copies per mL, whilst the Abbott BinaxNow test, for example, needs 1,000,000 viral copies per mL in order to get a positive signal.
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.
Vatic is a predictive health company focused on making medicine more proactive. We deliver on-the-spot tests which detect subtle biomarkers in people’s bodies to predict illness before it becomes acute or infectious.
Our first product is KnowNowᵀᴹ, a rapid turnaround COVID-19 antigen test, that is designed to identify COVID-positive people before they become highly infectious*, based on just a small saliva sample.
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.
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.