By now, we are all aware that the Coronavirus has become somewhat of an existential crisis to humanity. Various short term strategies have been proposed and deployed to slow down the virus. But we are playing catch-up with an exponential function. Are we doomed to massive lockdowns, a ruined economy, and hundreds of thousands of deaths while we await the vaccine to save those of us who survive?
The answer has to be no. And it is no. But it requires a comprehensive nationwide and worldwide strategy based on science and public health expertise. Will social distancing, stay-at-home, shelter-in-place and lockdowns get the job done? Are more widespread testing and more ICUs/ventilators the solution? Will some anti-viral drug turn out to be the silver bullet?
Some of the ideas described above will help slow down the virus, others may not pan out, but we need strategies beyond these ideas to systematically tame this virus and return society back to some semblance of normalcy within the next few months without watching our parents and grandparents meet lonely deaths.
In this diary, we provide a high level look at some long-term strategies that have been discussed that will probably provide a way out of this crisis. Many pandemic experts have been writing about this issue, but we have not reached consensus yet or taken any major steps towards a comprehensive strategy.
Some Baseline Strategies
The Imperial College report provided a baseline for two major narrowly focused strategies, pieces of which are being deployed in hard-hit areas across the U.S.
- Mitigation: Social distancing, isolate/quarantine all symptomatic cases and their families. For a period of 3 months.
- Suppression: Mitigation plus social distancing for the entire population, shut down all public gatherings/most workplaces, schools and universities. For 3+ months.
Mitigation “flattens” the curve a bit, reduces case fatalities by 50% which still numbers in the millions.
Suppression brings down the death rate substantially to a few thousand, but society cannot operate in this mode for 18 months until vaccines arrive. The report recommended lifting some of the suppression restraints periodically, watch the case rates go up and then go back to full suppression mode and repeat this many times over the 18 month period. This is not a sustainable model for 18 months.
So far, we have pretty much been implementing parts of these two techniques with no real long term strategy.
A more Comprehensive Strategy with Rapid Contact Tracing
The approach we will describe next is not entirely new, many experts have been advocating it, similar strategies based on Contact Tracing have been implemented in China, S. Korea, Singapore, Germany and parts of Italy and in past epidemics.
But we will walk through some simple examples to understand the underlying principles before we arrive at the heart of the solution.
Keep in mind, that what makes this virus so insidious is that after infection, most individual have no symptoms for an average of 5 days, yet they can spread the virus during the period. It’s this silent transmission which makes the virus so dangerous and hard to control.
1. Mass testing.
Let’s do a thought experiment. Suppose, starting tomorrow, we test every individual for the virus every day and produce results quickly. That’s an unrealistic number of tests, but bear with me. Individuals that test positive are immediately isolated at home or in designated quarantine units or hospitalized and treated, depending on their condition. Effectively, individuals that test positive can no longer transmit the virus to others. Individuals are released after a certain period and after 2 or more negative tests.
Within a few weeks, we will see the new infection rate drop to near zero. Not zero, since we may miss a certain percentage of cases. After that, we can return back to work, but the daily tests and the mitigation/treatment steps continue as long as needed.
Obviously, this is an academic exercise since we will not be able to scale testing to this level, but it provides us with some insights.
2. Fraction of population testing
What if we test not 100% but a smaller percentage, say 1% of the population (3 million) every day? If we do the math, this does not control the virus. We have to detect more cases than what the exponential curve is generating. We will need the percentage to be of the order of 33% to 50% to bring the effective transmission rate R0 down to below 1.0.
3. Test all infected people only
What if we test infected individuals only? Now that sounds like a bit of voodoo-science, but again this is an academic exercise which provides some insights.
Suppose we magically perform testing on a daily basis on only those who are infected. This reduces the number of tests required to a tiny fraction of what is required in #1 and has the same net effect as #1 — positive cases are quickly isolated from the rest of the population and infection rate comes down to near zero within a few weeks. This will work, but it is not possible.
4. Test mainly infected people via the technique of contact tracing
We can achieve an approximation to solution #3 by using the technique of contact tracing. The main idea behind contact tracing is to identify and test candidates who are likely to be infected, based on their contact with known infected individuals.
Consider the diagram below, that shows an individual I1 who on day 1 picked up the virus (or became infectious). On day 2, the individual came in close contact with 4 other individuals, 2 of whom got infected, as shown in red. On day 3, individual I1 and the 2 other infected individuals came in contact with 8 more individuals infecting 3 more and so on. On day 4, individual I1 develops symptoms, shows up at a clinic and tests positive. The other 10 infected cases are still out and about, asymptomatic, spreading the virus.
At this point the contact tracer group springs into action. They trace and identify all individuals that individual 1 had close contact within the last 5 days or so, notify them and immediately get them tested. The negative cases may be isolated for a few days, the positive cases are quarantined or hospitalized and treated. This process is repeated for all the identified positive cases and their contacts are traced in a similar manner.
One can see, that in principle, all the red (and blue) dots in the diagram can be identified and quarantined/hospitalized on day 4. This includes asymptomatic cases. That’s the power of this method. One could even try to discover the individuals who may have infected I1.
A few positive cases might get missed. But they will get picked up in the future.
This technique is not quite as strong at #3 but it comes close.
The technique has a few requirements for it to be successful —
- There must be sufficient number of tests available.
- The tests must be fast; waiting a few days for test results will defeat the whole purpose
- The contact tracing must be rapid and accurate. If it takes several days to find the contact chain, it reduces the efficacy of the process.
A few notes about this strategy- —
- This technique works best during the initial stages of the epidemic in any given area, when the number of cases is small. In later stages, this will generate a surge of positive cases before it dies down.
- Hence, it is best to employ social distancing and suppression techniques for a few weeks as contact tracing ramps up.
- In addition to isolating positive cases, places visited by them should be disinfected.
- Positive cases should be treated with approved and experimental drugs to reduce fatality rate
- Suspect cases may be assigned a risk factor based on various criteria to prioritize testing.
- Some people will be unnecessarily quarantined, that is the price we will pay. Those who have good social distancing skills will be less likely to end up in quarantine.
- The strategy will be less effective if quarantine is made voluntary.
- The strategy works better if it is deployed everywhere, not piecemeal. There is a temptation to avoid this in an area if case numbers look low. But that is precisely the right time to deploy this — the costs will be lower and the benefits will be much higher.
- Over time, the number of tests required for contact tracing will diminish. Extra test kits can be used to monitor critical personnel.
- Once the case levels drop off, businesses and schools can be opened up, but contact tracing should continue. Case levels and fatality rates will remain low.
- Done right, we can be back on our feet within a few months.
Trevor Bedford, an epidemiologist, has a twitter chain related to this approach and has a nice diagram to illustrate the principle.
The Elephant in the Room
Now, we get to the hard part of the strategy. How do we perform rapid contact tracing in a large population?
Traditionally, this been been done by humans — special contact tracer detectives perform the job of contacting individuals by phone or personal visits, and interviewing them to extract information about close contacts made and places visited. To find contacts in public places, the detectives look for indirect evidence, trying to locate people who visited a store during the wrong time and even relying on security cameras to identify them. It is a slow, painstaking and tedious process and takes time. It also misses a certain fraction of cases. This is what has been done in Singapore. Here is a video from Singapore explaining their fairly successful efforts in containing the virus -
Germany has used manual contact tracing with great success — it has one of the lowest fatality rate (there are other factors to responsible for that).
The other more effective technique that we occasionally hear about is technology and mobile phone tracking to perform contact tracing.
It is a fact, that most smart phones are tracked by phone companies and various downloaded apps. Most smart phones have GPS; phones are also tracked by cell towers, even inside underground shopping malls, subway stations and tunnels. In principle, every person’s location can be tracked minute-by-minute. From that data, one can derive who was within a few meters of another person and for how long at any time and date.
It is relatively easy to use this data to perform contact tracing — once an infected person is located, software can generate within milliseconds, all contacts of that person that satisfy certain criteria across a certain period of time.
Yes, this implies that some commercial or government organization will have access to personal data that can potentially be misused. It is not enough to use anonymized data. That is the dilemma we face. There are ways to protect this information from being leaking to unintended users, but as they say, nature and technology will find a way. Perhaps, the smart folks out there will come up with better techniques to safe-guard this information, or we will have to come up some other method to perform contact tracing.
If we decide to implement this or some variation thereof, how long will it take set up the software systems and train people (hospital staff, the police?, new specialists) to get the process moving? Probably weeks, but there are companies like Google and various startups that have the expertise to set up the IT systems for this use and who are already building apps for commerce and govt. that analyze anonymized mobile tracking data. China, Singapore and S. Korea have also offered to help.
Singapore also uses a contact tracing app which does not use location tracking but exchanges messages with other cell phones in the vicinity using bluetooth. Data is sent to a central repository which can trace contacts once an infected person is identified. Note that this is a bit weaker in capability than location tracing but less intrusive.
Other Steps
Note that there are several other well-known preparedness and mitigation steps that must be deployed in addition to contact mitigation, suppression and tracing -
- Keep social distancing, stay-at-home and shutdowns in place until infection rates come down.
- Build more hospital facilities to manage the surge in hospitalizations
- Increase the medical workforce
- Manufacture more face masks, ventilators, hospital equipment. Get industrial giants (e.g., auto manufacturers) to retool and produce hospital equipment. Find creative solutions, even if they are sub-optimal.
- Deploy the army engineering corps and/or army reserves to help build hospitals and isolation facilities and also help with logistics
- More aggressive and coordinated R&D on drugs, vaccines, trials and experiments.
- Antibody tests to identify patient who have recovered and therefore have immunity,
- Prioritize health workers’ physical and mental health
- Prioritize prevention and mitigation among seniors and senior care homes.
- Encourage wearing of medical masks or make-shift masks (e.g., scarves).
- Provide economic stimulus
- Provide financial relief to individuals and small businesses
- Educate, inform and provide guidance to the population. Provide accurate information. Prevent false information from spreading, esp. on social media.
- Develop online and mobile information bases and tools
- Let scientists and healthcare professionals take the lead and get politics (and racism) out of the public health business.
- All this needs to be done ASAP
Examples of Technology being used for Contact Tracing
Mobile apps and location tracking have been used in China, Singapore and South Korea to slow down Coronavirus. We wrote about it in diary Coronavirus Control - Novel High Tech. Solutions or Mass Surveillance?
In late February, China launched a smartphone app which took inputs from users and assigned a colored QR code to each user, based on factors like health and travel history, duration of time spent in infected areas and proximity to potential carriers of the virus. A green code means that the user can move around with relative freedom, while those with yellow or red badges must self-quarantine. Various checkpoints and businesses around the nation require a green code to permit people to let in or pass through. The ratings can change automatically, based on a user’s movement and new reports of infections.
Note that this goes a step beyond contact tracing. Everyone is forced to participate and to follow orders. Without a green code, one cannot move around and may face severe penalties or jail time. Security cameras are also used to catch cheaters.
On the positive side, this would prevent those at risk of infecting others from mingling in public places and businesses with others allowing healthy individuals to go about their daily work with more confidence. This is how they plan to open up Wuhan and other provinces. On the negative side this creates the potential for state surveillance at a scale never seen before.
If we thumb our noses at China for doing this, keep in mind that they have succeeded in slowing down Coronavirus and opening up businesses. They will succeed while we fiddle. Their economy will grow while we pontificate on strategies and watch millions die.
South Korea has used technology to help citizens make informed decisions. A popular app allows users to detect if a place has been visited by someone infected or suspected of infection. I do not think this data has been used for contact tracing. South Korea has used manual contact tracing and large number of tests to control the virus, without resorting to city lockdowns.
Testing
Right now, we are severely limited in out capacity to perform tests or to get results quickly. This will likely change in the next week or two as new tests and test equipment come to market, E.g., this announcement from Abbott Labs promises 5 minute test results (13 minutes for negative results) starting this week. There are others working on at-home “strip-tests” but that will not be ready for a few months.
Experts working on this problem
There are many other experts that have been beating the drum on similar approaches — Tom Inglesby, Dr. Tom Frieden, Jeremy Konyndyk, Caitlin Rivers, Dr. Angela Rasmussen, Carl T. Bergstrom, Trevor Bedford, and Ian M Mackay to name a few.
Scott Gottlieb, ex FDA Commissioner, co-authored this comprehensive plan this morning, whose main tenets seem to be along the lines described in this diary. Will the trump administration implement it? That remains a question.
Experts seem to be quite consistent on the overall nature of the strategy.
Epilogue
AFAIK, this is the only viable approach (or some variation thereof) that can put the world on a path of recovery in a matter of a few months and prevent large scale fatalities.
Given a comprehensive nationwide strategy, political will and competence, and public support, we can overcome the COVID-19 pandemic. We not have to live hunkered down for 18 months. Or we may end up doing so if the trump administration continues to rely on lies and deceptions to manage the Coronavirus crisis.
There will be personal suffering and tragedies, as family members get infected and quarantined. Many of the elderly will die — alone in a hospital bed and be buried/cremated quietly. We need to prepare for that.
Economic stagnation, shrinking nest eggs and job losses will occur. We need to prepare for that too.
None of this will be easy since we have an administration and a ruling party that values loyalty and ideology over competence and governance. We all know, trump and the GOP will lie, take steps reluctantly, use the occasion to demonize Democrats, blue states, China, immigrants, spend trillions of tax and borrowed dollars to shore up businesses and their rich buddies, take credit for every little improvement (real or manufactured) and blame Democrats for all bad news. We need to prepare for that too.
How will this play out politically, how will elections be effected, will Democracy survive — these are questions that will be discussed by the punditry class over the next few months, writing and talking from the confinements of their homes. We need to prepare for that too.
After we come out of this, how should our system be changed to prevent future disruptions? How should our healthcare system change? How should our economic system change? How should our political system change? There will be time to debate that.
Now, let’s hear your informed opinions. I suspect many of us will have the usual knee-jerk reaction to location tracking and privacy concerns, but do add some additional info how we can improve it, any alternatives you may have read about and your own insights on how we will end this crisis. Strategize not just about yourself, but about the community around you.
Let’s stay focused in this diary on solutions and avoid dwelling on the latest Coronavirus news or statistics or on trump and his daily lie-fest. Also, let’s stick to science and stories from reputable sources. Thanks.
Further Reading
- Impact of non-pharmaceutical interventions (NPIs) to reduce COVID19 mortality and healthcare demand — www.imperial.ac.uk/...
- National coronavirus response: A road map to reopening — www.aei.org/…
- The coronavirus is expanding the surveillance state. How will this play out? — www.washingtonpost.com/…
- Singapore says it will make its contact tracing tech freely available to developers — www.cnbc.com/…
- Coronavirus cases have dropped sharply in South Korea. What’s the secret to its success? — www.sciencemag.org/...
- What Malaysia Can Learn from China in Battling COVID-19 Using Digital Technologies — fintechnews.my/…
- Coronavirus Control - Novel High Tech. Solutions or Mass Surveillance? — www.dailykos.com/…
- Lessons from Italy’s Response to Coronavirus — hbr.org/…