Covid-19 Goals: What level of Containment?

The response of every state or country to to Covid-19 amounts to containment governed by:

  • A ‘too high‘ level when cases are too high, triggering increased lockdown measures and social distancing restrictions
  • A ‘low enough‘ level where it is considered safe to then relax lockdowns and/or social distancing restrictions

What obscures that fact that all plans are following this ‘containment’ pattern is that it can seem that no government has a clear vision as what the next ‘too high’ or ‘low enough’ level will be.

Containment in 1918

At the time of the 1918 flu pandemic, there was no internet, no mobile devices, no home radios, no televisions, no home refrigeration, and society was at the end of the worst war the world had seen. It was a very different world and far less was possible from home, and far less was possible economically. This made possible far less effective lockdowns than are possible in the 21st century. In 1981, ‘flattening the curve’ still resulted in spread ratios greater than 1.0.

St Louis flattened the curve compared to Philadelphia by introducing measures before cases began to rise. But even with measures in place, the ‘curve’ kept rising. A slower rise meant a ‘flatter’ curve, but the curve still kept going until ‘herd immunity’ and a huge death toll. In 1918, even with the best ‘lockdown’ possible in place, case numbers rose until, for example, 30% of people had been infected and lockdown herd immunity caused the curve to peak. The next decision was when was ‘low enough’ to remove the lockdown, and be hit be the second wave, as the immunity under lockdown does not provide immunity outside lockdown.

Blocking Lockdowns: Enabling Containment

Now in the 21st century, every country that wishes to has been able to introduce a ‘blocking lockdown’ that reduces infection rates to below 1.0 immediately the lockdown takes effect. Even in countries like Australia and New Zealand, where far less than 1% of people have been infected and there is effectively zero herd immunity, case numbers start falling.

This ability to introduce a lockdown ‘capping’ case numbers within a month from lockdown introduction gives far more control over containment.

But it also means that when case number start falling, there will most often be far, far less herd immunity than when cases started falling in 1918.

This ability to introduce a lockdown at any level of herd immunity provides.

Containment examples

Sweden: Sweden been perhaps been the only country to introduce lockdown measures specifically designed to not create a blocking lockdown, and deliberately allow cases to continue to rise. Is there a ‘too high’ level of cases of cases per day where lockdowns in Sweden will increase? I hard heard of no figure announced, but it seems logical there would be such a figure.

New Zealand: An opposite extreme to Sweden is New Zealand, with approximately 102 confirmed cases when the country first entered level 3 lockdown and March 23. Exiting lockdown with zero herd immunity, extreme vigilance is required, but extreme vigilance and track and tracing becomes possible with almost zero cases.

High Level Containment.

Surely it is easy to contain a beast within a larger pen, so keeping Covid-19 cases below a high threshold must be easier than a low threshold? The problem with the ‘pen’ analogy is that the Covid-19 beast grows larger to fill the larger pen, and that larger beast is not easy to contain. The result of high level containment is more cases and more deaths, all the way to herd immunity, which will at least be reached earlier.

If there is a lockdown of any form, then lockdown herd immunity is all that will be reached under lockdown. For example, Sweden does appear to have reached lockdown herd immunity. But with 26,000 confirmed cases from a population of 10 million, even if real cases are 10x confirmed cases there is only 2.5% of people now immune. At the current rate, immunity is increasing extremely slowly an may not change significantly before a vaccine is available.

The high level containment was obtained in Sweden by a lockdown that in hindsight seems to have achieved very close to a 1.0 spread rate. So close to 1.0 that 2.5% of the population is sufficient to bring the rate to exactly 1.0 or even below? It is a little more complex, but it also seems that as the rate climbs then social distancing behaviour has increase so the lockdown has become more effective. This may have had more effect than any acquired immunity, but it is complex.

The cost of this more relaxed lockdown has been over 3,000 deaths and a current daily death rate at least 50x higher per capita than in countries following low level containment. Plus the fact that there is no basis for further relaxation of the lockdown.

The incentive for the high level containment? Economic benefits from the more relaxed lockdown. The test will be if the longer lockdown than with low level containment will realise any real long term economic benefit.

Low Level Containment.

The smaller the ‘beast’, the easier it is to contain. With a very low number of cases, significant effort can be allocated to ensuring no case results is linked to further spread. With high cases numbers, there will be cases throughout the community, and lockdown measures sufficiently strict to keep the spread below 1.0 must also apply throughout the community. With low case numbers where cases can be isolated, most of the community can live under more relaxed measures. When there is a case, then each case can be treated as potential cluster limiting the stricter lockdown measures to the relevant location. Relaxed lockdowns for the rest of the community requires vigilance, testing, and strong track and trace, but has been shown to be able to be successful.

South Korea and New Zealand are examples where containment has focused on eradication. South Korea, with 5x the population of Sweden has 258 deaths at the time of writing, 5 deaths per million compared with over 300 deaths per million in Sweden. New Zealand so far has even lower infection and death rates.

Lockdowns in Korea have been more restrictive in some ways than in Sweden, but they also have been able to in other way enjoy more freedom and less disruption. The Hyundai car plant in Korea has had short term lockdowns, but for much shorter times and less disruption than Volvo plants in Sweden.

Note that while Korea is an example for low level containment, it is not the least disrupted low level containment country in the world. Taiwan, started low level containment strategy before cases even began to rise, avoiding the need to have lockdowns to get the levels low. This has allowed all businesses and schools to continue, with not only minimised economic impacts, but deaths in Taiwan have so far been limited to 7 and total cases to 440. Further confirming that best economic results and best health outcomes go hand in hand. (Update: also consider Vietnam with zero deaths)

Mid-Level Containment: Politics?

Germany did not reach a ‘low enough‘ threshold sufficiently low enough to qualify as ‘low level containment’ prior to relaxing lockdown measures. The declared ‘too high‘ threshold at 50 cases per 100,000 people, does not qualify as ‘high level containment, with action to be taken well below infection rates of neighbouring Sweden.

In fact, it seems as with many other countries, lockdowns were eased in response to political pressure as much as in response to actually reaching low level thresholds. The result has been that even for a country with a strong testing regime and relatively better management of the outbreak, easing lockdowns has resulted in the risk of the outbreak getting out of control.

Given that the higher the case load the more difficult the containment, the main reasons for easing lockdowns before achieving low levels seem to be:

  1. politics and pressure from various groups
  2. economic hardship under lockdown that cannot be endured

Given that the cost of easing lockdowns too early or too far is either a far more significant death toll or even more time in lockdown than was saved by the early exit, this leaves many countries in a very difficult position.

Conclusion.

The main reason countries end up with a ‘mid level containment’ strategy the difficultly maintaining political resolve. A clear signal of the lack of political resolve is that while most countries have a policy of lockdowns for when cases are ‘too high’ and relaxation when cases are ‘low enough’, but almost no country is prepared to declare in advance what ‘too high’ is or what is ‘low enough’. Decisions are made ‘on the fly’ in order to allow for accommodating political popularity of the decision at the time.

Despite Sweden displaying the strength of their society by managing an exemplary attempt at higher level containment, it is difficult at this time to see how long term economic outcomes will better low level containment countries, and clearly the human cost has been high.

Higher level containment appears to result in an inferior outcome to low level containment, and anything in between seems to offer nothing but greater devastation to both economy and people.

Lower level containment seems the best solution, but it requires the political will and an economic system with the strength to resist early lockdown exits.

What is limiting achieving the best outcome is ability to resist political pressure to unlock too early and the economic system to support seeing through the lockdowns until case numbers are low.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Blog at WordPress.com.

Up ↑

%d bloggers like this: