Thread by @yaneerbaryam

New Paper: Mass testing to end the COVID-19 public health threat

“many countries have let the virus spread more or less freely, individuals and communities are now grappling with many negative health effects & economic ramifications #COVID19 #Testing
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sciencedirect.com/science/articl…

“it is increasingly clear that the policy vacuum comes at an unacceptable price both in the short and long term..we need tools..that can effectively control transmission of rapidly spreading new variants” #COVID19 #Testing
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“Otherwise, we may face significant disruptions and enormous costs due to repeated waves of illness, with each wave increasing the numbers of workers thrown out of the workforce from long term health effects. #COVID19 #Testing

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“Lockdowns, due to their social restrictions and high short-term economic costs, are no longer the best available option.” #COVID19 #Testing

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"We here point out that mass testing (regular asymptomatic screening of the general population) is an alternative approach that can dramatically reduce cases and quickly restore economic and social activity. #COVID19 #Testing

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"Testing has been identified as a crucial and potent tool to reduce transmission.If everyone takes a rapid PCR or LAMP test once per day and those that test positive are then quickly isolated, a 30-fold reduction in effective reproductive number R is possible.#COVID19 #Testing
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"If we assume R = 10 without testing, we might expect daily testing to reduce the number of new cases by greater than a factor of 9 each week; mass testing would not only reduce R but also the serial and generation intervals. #COVID19 #Testing
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"This is a tremendous reduction and can be as, or even more effective, than a strict lockdown, which early on was shown to reduce R by a factor of ≈ 5–10. Robustness of elimination due to mass testing..is possible even with significant non-compliance.
#COVID19 #TESTING
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"Elimination can always be recovered by increasing the test frequency and/or reducing virus spreading using high-quality masks, HEPA purifiers in schools, restaurants & workplaces or additional surveillance strategies (wastewater, surface or air monitoring).
#COVID19 #TESTING
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As variants continue to increase the transmission rate, test frequencies higher than daily maybe needed. Fortunately, gargle-spit sampling is effective and allows taking samples at home, where it can be integrated into daily routines such as toothbrushing morning & evening.
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Also sample collection or drop off can be part of daily procedures by collecting samples at work or larger supermarket chains as done in Austria. In order to implement the strategy of mass testing, almost everyone in a certain geographic area will need to be tested regularly. /11

Once a geographic area is cleared of the virus, test frequency can be reduced, further reducing financial costs, time, and efforts spent on testing. Subsequently, testing can be focused on areas that still have community transmission or in which there are new outbreaks..
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"Elimination can be preserved without strong border controls using general testing twice per week (to achieve R/10 rather than R/30) and daily testing of cross border travelers for two weeks.
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"Non-intrusive HEPA purification in restaurants, retail and workplaces and masking where needed, should continue for robustness in preventing new outbreaks.
#COVID19 #TESTING
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Economy:

Mass testing impacts the economy far less than a lockdown, and results in far less social disruption. Calculations by Institut économique Molinari..show, if France, Germany, the EU, or the US were to implement mass testing..at 10 dollars a test,
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#COVID19 #TESTING

"the cost..would respectively be 12 times, 8 times, 9 and 7 times lower than the loss of GDP.. Test costs of 10 dollars..can and are being realized using pooling strategies..LAMP tests start at 5 euros per test and pooling..can reduce the costs by an additional factor of 5.
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This strategy will not only reduce the amount of illness and suffering in the population but likely also still be financially profitable; although society has opened up, the accelerating costs of long COVID,

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#COVID19 #TESTING

"..and the increase in prevalence of many other medical conditions after COVID-19, continue to mount with the continuous increase in new cases. The cost of long COVID with today's knowledge was recently estimated to equal the cost of the great recession.
#COVID19 #TESTING
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Feasibility:

The feasibility has not only been described repeatedly on theoretical grounds, but has also been demonstrated practically in several countries and on various scales. One of the most impressive recent demonstrations..has been rolled out in Germany.
#COVID19
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"In the state of North Rhine-Westphalia, with a population of nearly 18 Million the most populated state of Germany, a pooled PCR test strategy was implemented in 3700 schools and 698 daycare facilities.
#COVID19 #TESTING
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"More than 800,000 individuals were screened twice per week using pooled-RT-PCR, with a total number of swabs of almost 17,000,000 within 13 weeks. 
#COVID19 #TESTING
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For easy sample acquisition the Lolly (lollypop) method was introduced, which was very well received, even within daycare facilities, showing testing can be incorporated into people's daily routines. Importantly, this also demonstrates the robustness of mass testing.
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"As the sensitivity was still sufficient at pooling of up to 200 people, the pool size is limited by the number of infections only. Indeed, the optimal pool size..increases as the number of infections goes down.
#COVID19 #TESTING
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"At 100 infections per Million people, the pool size could..be increased to ∼100 people per pool. At such low infection rates, the continuous surveillance of an entire German elementary school would therefore produce the costs equivalent to 3 PCR tests a few times a week..
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"..and even a soccer game, with 40,000 visitors, could be monitored with just a few hundred PCR tests allowing to keep schools, social gatherings as well as the economy open and safe.
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But there are more examples showing feasibility of the concept, such as at the University of Davis,. the NBA (National Basketball League) strategy to create a bubble or during the Tokyo Olympics are good role models of how a mass testing strategy could be brought to reality.
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Summary:

Sufficiently high rates of mass testing can replace lockdowns as the main tool to reduce transmission. When combined with other measures it helps achieve the shortest pandemic intervention that can stop social and health collateral damage and keep the economy open.
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"It is a less expensive, less interfering but highly effective and complementary risk mitigation tool compared to measures such as stay-at-home orders, while ensuring that most people stay healthy.
#COVID19 #TESTING
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"If implemented on a larger scale, mass testing may propel the world towards a real end to this pandemic without the need of lockdowns.
#COVID19 #TESTING
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"Here we have discussed the opportunity to stop transmission using alternatives to lockdowns. Given the ongoing level of disease and long COVID accumulating in the population, the consequences for health, social stability, and economy even with vaccination are significant..
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"..and require a reconsideration of the currently prevailing strategy.

@CecPhil @M_F_Schneider @smbilodeau
@GANyborg @ShutiChiou @cgg_mx @SunilRaina15

#CovidIsNotOver
@TheWHN
@TheLancet
@LancetRH_Europe

sciencedirect.com/science/articl…
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Here is the technical appendix with calculations of the rate of decrease of transmission with testing frequency and other parameters:
#COVID19 #TESTING
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Completion of the transmission calculation and tables for economic calculations
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Additional relevant references

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