There are various clear arguments about why social distancing is important in managing the pandemic.
Most would agree that obviously distancing will reduce spreading. But many people might wonder why it is necessary to continue social distancing even when case numbers are dropping, or when the situation appears to have improved, especially when distancing measures are causing such hardship.
When considering any sort of physical system or intervention, it is often interesting, logically, to consider what happens when an intervention is applied at the theoretical extremes.
Thought experiment #1: the two hypothetical extremes of social distancing
The two extremes for social distancing would be the following:
case #1) every person on earth (all 7.8 billion of us) would maintain over 2 metres (6 feet) of distance from every other person on earth, continuously for the next 4-6 weeks.
case #2) every person on earth (all 7.8 billion of us) would have direct contact (maybe a handshake, a hug, and a kiss) with every other human on earth, all in the same day!
What would happen with each of these extremes, given current COVID-19 infections?
Case #1: with maximum social distancing, pandemic over in 6 weeks, with 10 000 to 100 000 deaths
In case #1, there would be no spreading. Of the current 10 million or so people who might carry the virus at the beginning of the 6 week period, perhaps 0.1 - 1% would die, which means 10 000 - 100 000 deaths. This is the lowest possible number of deaths from the pandemic, unless a cure is found in the next 6 weeks.
After that 4-6 week period, the virus would be gone, and COVID-19 would no longer exist in the human population, unless it was introduced again from animals. The pandemic would be permanently, completely over. A variety of other human diseases would probably be greatly reduced as well.
Case #2: with maximum social contact, pandemic over in 6 weeks, with up to 160 million deaths
In case #2, everyone would contract the virus. The death rate would be higher than case #1 since health care resources would be massively overwhelmed. Let's say a 2 % death rate, which means 160 million deaths, all over a 1-2 month period, which would basically be the worst devastation in human history. After this point, the virus would also most likely be done, people would probably be immune, and the pandemic would be over.
We can see by comparing case #1 and case #2, which differ only in how much social distancing took place, that social distancing has a clear , huge effect on mortality. The maximum effect of social distancing alone would be to reduce deaths about a thousand-fold and to put an end to the pandemic.
Conclusion: By social distancing alone, it is possible to theoretically end the pandemic in 6 weeks, with a minimum of fatalities. But of course such a plan would prevent most normal activities in society for over a month.
Thought experiment #2: the two hypothetical extremes of testing
The two extremes of testing are as follows:
case 3) Every person could instantaneously know if they were a viral carrier, at every moment. An imaginary device to accomplish this would, for example, be an electronic monitor that everyone would wear, that would instantaneously light up if a virus was detected in someone's exhaled breath.
A watered-down version of this, which is theoretically possible at present (if not feasible at scale yet), would be to have every person in the population tested every single day, with results available in minutes.
case 4) No testing at all would take place. This is not far from what is really happening in some places.
What could happen in each of these cases?
Case #3: with maximum testing, pandemic over in 6 weeks, 10 000 to 100 000 deaths, with minimal disruption to daily quality of life
Every person with virus detected could promptly isolate, eliminating any chance of spread. Since the tests would be done continuously on all people, there would be no chance for asymptomatic spreading. The mortality result would be similar to Case #1 above, with the pandemic over in 6 weeks, with under 100 000 deaths. But unlike Case #1 above, Case #3 would only require a 6-week isolation of the 1% or so of the population which carries the virus. The other 99% of us would be entirely free to live normally, with no social distancing required.
Case #4: with no testing, pandemic over in years, or never over, with 4 million deaths
With no testing, we would have gradual spread to the entire population, occurring over a period of months to years. It would continue spreading because of asymptomatic transmission. We could assume a lower death rate than case #2, since the health system would be less overwhelmed, and there would also be more time to develop better treatments. So let us assume a 0.05% death rate overall. This means about 4 million deaths.
Conclusion: testing, done as frequently as possible, and of as many people in the population as possible, has a clear, huge effect on mortality, on the duration of the pandemic, and on preserving a more normal quality of life. Testing and isolating alone could also end the pandemic in 6 weeks, with a minimum of life or economic disruption.
What conclusions can we take from these hypothetical thought-experiments?
Social distancing obviously works. The logic above shows it. It needs to be extremely rigorous and disciplined, with everyone participating, in order for it to help best. If some people are not participating, the virus still has a chance to spread.
There are actions that will increase the effectiveness of social distancing, to “magnify” it if you will. These actions include widespread face mask usage, plastic barriers, hand-washing, and frequent disinfection.
Frequent testing also works. Experiments are not necessary to prove this. The logic outlined above proves it! With a maximum of testing, the pandemic could be over in 6 weeks, but unlike the social distancing technique, it would require much less disruption to the population, to lifestyle, and to the economy.
In practice, we are imperfect people, our governments are very imperfect, and also the technology required to put these two types of ideas into place are limited. It takes time and money to manufacture test kits and to develop the infrastructure to distribute or administer them, and to arrange to isolate every positive.
What can we do in the meantime? Individuals do not have the power to make more frequent testing happen. But individuals can adhere to social distancing with as much discipline as possible. This clearly will help.
What can businesses, schools, churches, and other group organizations do? They can enforce rules of social distancing for their employees, students, or members. They can sponsor campaigns to persuade others to follow the rules. They could use their political influence to urge governments to do the same.
Industries could participate, to the best of their ability, in the mass-manufacture of testing kits if possible, and of other useful technology, such as masks.
Governments have some power to enforce social distancing, and in my opinion they should use it, if they want the pandemic to end sooner, to save more lives, and to get the economy going sooner.
Governments and industry also have the power to maximize the production and deployment of tests. If the number of tests could be increased 10-fold, or 100-fold, or 1000-fold compared to where they are now, this will put a very powerful brake on the pandemic, and give us the chance to eliminate the virus entirely, with the smallest possible disruption to our lives. Really, I don't understand what they have been waiting for; every day of not maximizing test kit production is a day of needlessly careening towards greater and greater catastrophe and death.
If both distancing and testing are done in a non-committal, half-hearted, slipshod manner, then there will be probably some reduction in case numbers, a "bending of the curve," but the pandemic will drag on possibly for years, or until a vaccine is found to work, is mass-produced, and given to the entire population.
There are, of course, other things to work on towards solving the COVID-19 problem, especially vaccine development. But this is likely to take quite a long time. It would be unprecedented for a new effective vaccine to be available within a year. But then, I am always amazed with what human ingenuity can accomplish, so I wouldn't be surprised if a good vaccine is indeed developed in record time.
There is also the hope that new, more effective drug treatments can be found. This research is just beginning to hint at some more effective developments. I wouldn't be surprised if much better drug treatments will come along in the next months as well.