REOPENING ECONOMIES & FLIGHTS IN A COVID19 WORLD

Aug 20, 2020

Governments world-wide are desperate to reopen their economies, and international air travel has been drastically reduced. Much has been made about the importance of proper testing, the funding provided, and the number of tests performed. The global media often robustly conveys efforts by governments to control Covid-19, yet after eight months, the rate of infections are only accelerating in the USA, Brazil, India, Russia, Indonesia, and others, many with dubious statistics.

The NEJM Stresses the need for high accuracy testing. A New England Journal of Medicine article (https://www.nejm.org/doi/pdf/10.1056/NEJMp2015897? articleTools=true), lays the blame squarely on the inaccuracy of Covid-19 tests, that give rise to too many cases of False Negatives. False Negative infected persons, a significant percentage being asymptomatic for weeks, are capable of infecting others, and some may even be super-spreaders infecting scores of others when testing accuracies are low.

Opening Flights without Accurate Tests. Countries that have reopened international transportation and their borders have experienced a resurgence in Covid-19 infections despite stringent measures and mandatory quarantine protocol.

The NEJM authors resoundingly demonstrate how improving testing accuracy for the SARS-CoV-2 virus is critical towards achieving those objectives. The graphs on page 3 of the article are seminal towards understanding their assertions in this regard.

To understand the implications of the NEJM article better, please refer to the Excel sheet (below) with tab: “Explaining NEJM Aug 6 Article”. The orange row in the table shows the results of using a test with 70% sensitivity and 95% specificity, while the blue row is for the test with 90% sensitivity and 95% specificity. The top row shows the assumed level of infectivity in the population.

Thus, using a test with 70% Sensitivity and 95% Specificity (orange row) in a test population with 15% infectivity rate, it is likely that 5 persons out of every 100 that tested negative actually are positive with Covid-19, and every 29 persons out of 100 that tested positive for Covid-19 are actually free from the disease! How many people would feel comfortable travelling in a large wide-body jet knowing that there are at least 15 infected persons amongst them?

Using a test with 90% Sensitivity and 95% Specificity (blue row) in a test population with 15% infectivity rate, it is likely that 2 persons out of every 100 that tested negative actually are Positive with Covid-19, and every 24 persons out of 100 that tested positive for Covid-19 are actually free from the disease. Thus, with a more accurate test kit, one can be more confident of a test negative result. Nonetheless, in a jet with over 300 people, there would likely be 5 infected persons which is still too high an infection risk to the rest of the passengers and to the recipient country.

The yellow row shows the results for 2 famous brands of Antigen-based test kits that have accuracies less than 90%. Even at 15% population infectivity rate, there are likely to be 3 False Negatives amongst every 100 testees with negative results. This is far too unreliable a test kit to use when deciding on whether to let passengers on to a plane, or whether to allow workers to enter a mission critical facility!

Finally, the green row shows the results of one of the 2 brands mentioned above, whose management claimed that they have attained a test sensitivity of 96.7%. Obviously, the results have improved, and to only 1 False Negative per 100 tested negative. However, according to reports, such claimed improvement in accuracy is only attainable for test subjects tested within five days of the onset of patient symptoms. Given that scientists have found that patient infectivity is strongest in the first week of infection and drops off quickly thereafter, but symptoms begin only 5-7 days post- infection, it would mean that this 96.7% accuracy rate is achievable when the patient’s infectivity has declined, missing out on the period when he is most infectious. The problem is further compounded by the fact that anything from 20% to 70% of infected persons are asymptomatic, and if so, what test accuracies could then be attained with these patients?

 

Note that the scenarios worked out above, and the illustrations, assume a one-person to one-test regime, but if pool testing is implemented, the frustrations caused to innocent passengers, or to employers of mission critical staff would be significantly magnified.

Conclusion. Governments could demonstrate their commitment to reopening transportation, economies and their borders by focusing on deploying the most accurate and rapid Covid-19 tests. Doing so gives realistic confidence to host governments, and concomitant to vast improvements in emotional and psychological benefits, the overall systemic cost of reopening economies will drop dramatically without quarantine and unnecessary treatments for those falsely diagnosed as infected.

Governments and their appropriate ministries should review the steps taken to effectively mitigate the risks driving the Covid-19 pandemic, especially given that the necessary tests to accurately identify infected individuals are available and affordable.

 

CHAN KP

Everdon Ltd.

+65 9880 0400

chankp@everdon.net

Brian James TRACEY

Design Security Ltd

+65 9638 1227 BrianJTracey@designsecurityltd.com

Everdon Ltd. is the authorised worldwide distributor of iONEBIO’s iLAMP NOVEL CoV-19 Test Kit that has 100% accuracy, 100% specificity and 100% sensitivity requiring a LoD of 2.5 with a PCR Assay time of less than 20 minutes.

Rapid Testing with Uncompromised Accuracy

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