covid-19 Crossing the Rubicon

As far as I can make out, Australia is now fully committed to a policy of “Adapt and Control” as opposed to “Eradicate”.

This means infection rates will continue to grow, at first gradually and then suddenly.

The intention is to avoid the hospitals being overwhelmed while gradually lifting restrictions to get people back to work.

There is already an increase in the reproduction rate, “R”, above 1, from the reduced physical distancing that inevitably followed the announcements of success and plans to remove restrictions. It started rising weeks ago, which was triumphantly announced as still being below 1.

That growth is starting from a very low rate of community transmission, so the growth will initially again be “gradual”. But community transmission means untrackable and uncontrolled transmission. “Community” transmission is not stopped by testing and contact tracing because the carriers are often pre-clinical and don’t get tested. It is only limited by physical distancing preventing transmission. Lifting the restrictions simply means there is nothing to prevent community transmission growing again, at first gradually and then suddenly. This shows up weeks later as the numbers of known cases growing gradually and then suddenly and later still for the numbers of deaths.

Opening the schools removes the main obstacle to getting people back to work and at the same time opens a channel for wider spread of infections among households via schools even while the faster transmission between households via workplaces remains restricted.

As infected school children tend to have mild or no symptoms it is likely that they are less infectious and so transmission between them in schools would be relatively slow compared with transmission between adults at workplaces. That has been presented as though a slow rate of transmission means a decline in cases – with “evidence” such as the low numbers of clusters among school children and of household transmission from children to adults. But we don’t know much about mild or asymptomatic cases because pre-clinical cases obviously do not get much clinical study since they don’t seek clinical assistance. If some of them last longer than more severe cases that trigger an immune system response or result in long term carriers, then a slow rate of transmission can still result in a larger than 1 rate of reproduction, sufficient to cause a (slower) epidemic.

But we don’t actually even know whether or to what extent infected children are less infectious than infected adults. Droplets are the main source of contagion, direct and via surfaces with transfer from hands to face. One would certainly expect that to be greater with symptoms such as coughs and sneezes that actually project droplets. Hence the emphasis on physical distancing together with washing hands and covering coughs and sneezes. Aerosol transmission by simply breathing is mainly known to be important in a healthcare setting where there is continuous close contact with infected patients. But aerosol transmission is important enough that religious ceremonies now permitted even in confined spaces in Germany are not permitted to sing. Singing projects larger quantities of virus into a confined space than merely breathing or talking, even though it does so less than coughing or sneezing. The cumulative effect of being confined in the same classroom as an infected child for hours each day over several weeks is simply not known.

The available evidence is quite sufficient to convince everybody who is utterly determined to get kids back to school so that their parents can get back to work. They are all chanting about it in unison. But since they live off other people’s work their livelihoods depend on them not understanding.

For example the livelihood of lobbyists for pubs depends on believing that a pub could maintain social distancing of 1.5m between customers if it was permitted to cram them in at 1 per 2 square metre instead of the current limit of 1 per 4. Consequently they can adamantly demand that the number allowed in be doubled so that they might be able to reopen some pubs. It simply does not matter that it would be physically impossible for anybody to get in or out. Their role is to lobby, not to understand things that their livelihood depends on them not understanding.

Rather more evidence should be needed to convince others. Why should one expect to have seen clusters among school children, given that children were withdrawn from schools well before governments shut them? Why would one expect a child to be reported as the first case in a household given that they usually only have mild or no symptoms? I would expect the first case reported to be someone with more severe symptoms who got tested as a result, with any child in the house subsequently found to be infected likely to be recorded as only as a subsequent case assumed to have been infected by the adult.

School childrn will now be spending many hours a day in the same confined classroom space with a cumulative effect on other children and teachers. So it may be possible there could be a gradual but substantial increase in the numbers of infected children before there is enough onwards transmission to more severe cases among teachers and households for this increase to be picked up from surveillance testing and contact tracing.

That could result in a substantial overshoot with the numbers of cases picking up again until it becomes necessary to slam on the brakes again.

The public health officials taking these decisions are not in the same position as politicians mouthing off. They have serious powers, responsibilities and duties, with corresponding legal liabilities for negligence, misconduct or refusal to perform those duties.

I don’t see how it would be possible to avoid a second wave from pre-clinical transmission given that the reproduction rate for pre-clinical transmission without physical distancing is itself nearly enough to cause an epidemic. The peak transmission rate for each case tends to occur just before they start to show symptoms so they are only tested after having already had the opportunity to infect others. We are starting from a position with the effective rate already above 1 even before the actual removal of restrictions.

If the decision makers have got it right, that second wave will be smaller than the first wave. They will be able to avoid overwhelming the health system while still substantially raising the numbers of cases and deaths, for some significant increase in the numbers back at work.

If they got it wrong there might be a more sudden increase in infection rates that discredits the “Adapt and Control” policy and forces a serious attempt at “Eradication”.

But I don’t see much likelihood of that reversal unless they get it so wrong that there is again a serious danger of the health system being overwhelmed. Nor do I see that as likely in Australia. The danger arose from failure to prepare in advance and was averted by the few weeks warning from the collapse in Italy. The next demonstration of spectacular incompetence seems more likely to be about something else rather than acting even slower for a second wave than for the first. It would require criminal misconduct rather than mere negligence and failure to perform duties for the brakes not to be slammed on before a second wave overwhelmed the hospitals. In Australia the consequences are likely to be a longer economic shutdown rather than an overwhelmed hospital system. The same may not be true in many parts of the USA and Europe and it certainly won’t be true in most of the countries ruled by kleptocrats.

I don’t know whether “Eradication” was likely to succeed. But we did have the option to try and no attempt has been made to find out. Australia still doesn’t have any seriouis modelling capability. Other developed countries did not have that option.

If an attempt had been made and had been successful, it could only have resulted in “Zero Tolerance” for outbreaks rather than zero outbreaks. There would have inevitably been occasional outbreaks, but only sporadically with each outbreak or set of outbreaks stamped out rather than becoming a continuous background rate of infection that would continue to grow, again at first gradually and then suddenly. Eradication means preventing that initial gradual growth, not preventing all outbreaks. The resources available for testing and quarantaining contacts and their contacts (“even unto the fourth generation”) are sufficient for sporadic outbreaks, but would be quickly overwhelmed when outbreaks become continuous rather than sporadic. Contact tracing is much easier when people have few contacts because they only go out for “essentials”. What was achieved by contact tracing under recent restrictions won’t still be possible without those restrictions. The last announced numbers for downloads of the “CovidSafe” tracing app would only cover less than 5% of contacts.

“Occasional outbreaks” seems to be what is being sold to people now. The story is that we can have less physical distancing and more people going to work or school together in confined spaces at the cost of some occasional outbreaks that will be kept under control.

That could have been true if we had Eradication first – i.e. zero community transmission for a few weeks before starting to ease up. It might even still be true for Western Australia etc. But it seems pretty implausble for Victoria and NSW now.

It remains to be seen how many people they will be able to get back to work but it seems reasonably certain that any economic recovery will be much slower than if there had been a successful Eradication first.

There doesn’t seem much hope of those responsible for this policy doing much to help other countries in a far worse situation, eg our neighbours in Papua New Guinea and Indonesia. They will be far too busy trying to drive people back to work.

For those in the vulnerable categories the danger of infection will now become significantly greater than it was with tighter restrictions and will remain present until a vaccine is developed.

What remains to be seen is how much longer people will remain tolerant of a ruling class whose unfitness to rule is now a matter of life and death.

4 thoughts on “covid-19 Crossing the Rubicon

  1. Hi Arthur, I think that the virus is over bar the shouting and I think this is because we the people and our rulers have learnt from our experience. The places where covid 19 got out of control was in the great municipalities NYC, London, Wuhan etc etc. and where leaders took a cavalier attitude USA, England, Brazil and Belgium come to mind. People have changed behaviour. Here in Adelaide we have zero active cases but people take the distancing seriously, go to Bunnings 4 people per isle, try to go to work with a cold, hand cleanliness is every where to be seen.
    As to the authorities do you think that they will let another Ruby Princess occur? Speaking of cruise ships they are taking bookings for a restart in August who would have thought.
    Clearly there is a dynamic between safety and the economy with the premiers of NSW and WA trading barbs. Excellent come back from the WA guy who said that yeah hes likely to take border advice from the people who gave us the Ruby Princess.
    There is a real struggle within ruling circles but as with any social struggle working people are also divided lots of people want to go to work lots of people want to keep a tight leash on this thing.
    As Alan Joyce says about Qantas just pack em in like sardines theres no issue. Not to him any way.
    If we get a second wave we know what to do but Im a bit unsure whether I should inject the bleach IV or intra muscular.

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    • In any class society the ruling ideas are the ideas of the ruling class. Of course workers are “divided” and many will continue to be more “cautious” than their ‘heroic” bosses determined to “boldly” shout that the virus is over bar the shouting. But they still have to go to work, and therefore have to send their children to school when governments stop public health expenditues enabling them to avoid fueling an epidemic “at enormous expense”.

      There is fundamental agreement in Australia on actively preventing the virus getting “out of control” as it did in Wuhan, Milan, London and New York”. But there is no agreement on what being “under control” looks like or what leash is tight enough or too tight.

      That has an inevitable tendency for the leash to slip and the level of control to be weakened over time. As I explained, that can be expected to result in infection levels and deaths rising, at first gradually. When they then start rising suddenly again it is reasonable to expect that the leash will be tightened in time to avoid an “out of control” situation. That pattern of successive waves over the next 12 to 18 months or more until a vaccine was modelled in the Imperial College covid-19 response team report 9. That is now policy. No attempt at eradication is being made in the three largest States.

      Western Australia, South Australia, NT and perhaps Tasmania (as well as the irrelevant ACT) might theoretically still have the option of eradication instead. But it is very theoretical given that Queensland, New South Walves and Victoria have all agreed to cross the Rubicon while there is still a small rate of ongoing “community transmission” that is only controlled by physical distancing etc. Since the smaller States and Territories are part of the same national economy it is more likely that they will end up with the same national epidemics, with varying lags (although still possible to avoid this).

      The virus is not over. The “jolt” administered by State Governments in NSW and Victoria succeeded in getting everybody’s attention by enforcing a ban on gatherings of more than two people. But that is now over and the jolt will fade as more and more people think it is “over” given the extremely low rates of community transmission. It looks like just “sporadic outbreaks” which would continue to need suppression even if eradication had been tried and succeeded.

      But it is precisely the belief that the virus is over that ensures infection rates will rise. Neither the virus, nor the susceptibility to it of nearly 100% of the population has changed at all. What changed was the reduction in contacts that reduced transmission, plus the enforcement of border controls. Continuing border controls plus long lasting behavioural changes might well slow down the rate of growth enough so that combined with surge capacity for testing, contact tracing and hospitals it is reasonable to expect future waves will be kept “under control” instead of overwhelming the hospital system.

      But there is no reason to assume such behavioural changes and border controls alone are now enough to prevent such waves happening at first gradually and then suddenly. Until a vaccine is developed the meausures that can control “community transmission” had to include shutting down community contacts. That was far more of a behvaioural change than will continue as people go back to school and work.

      This should be obvious in Adelaide where public transport is already cramming people into conditions ideal for spreading infection. The results will be gradual because the initial numbers infected are so low. But that merely means it takes a while to show up at all, and even longer for it to show up in confirmed cases, hospitalizations and eventually deaths.

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  2. Hi Arthur my point is that the virus is a non thinking bit of nucleic acid wrapped in a bit of protein. It has a simple unchanging but highly effective strategy. People in lots of places seem to have adopted strategies that have it under control and some lucky end of the earth places like Adelaide seem to have achieved eradication and yes public transport is one of our Achilles heals. I am at a loss to think that we the thinking end of this equation cant defeat the non thinking end. Even the evil bastards at WSJ and Sky have a strategy its just that their strategy prizes profits over people where as we the people would like the slogan to read people before profits. We have come a long way since we faced the flu pandemic of 1968 where our strategy was do nothing and just let a million people die. A lot of effort is going into a vaccine but its arguable that this thing will have passed before one is developed even if one can be developed

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    • Anything is “arguable” but I am not aware of any epidemiologists who seriously believe that “this thing will have passed” prior to a vaccine being developed. There are virologists who consider it quite likely a vaccine will not be developed in the forseeable future. But the inevitable epidemiological conclusion if that turns out to be the case is not that “this thing will have passed” but that this thing will have become endemic – like regular bouts of “the cold” from rhinoviruses.

      The ONLY strategy that is known to keep a disease that has no vaccine under control ANYWAY has been the various forms of preventing transmission through quarantine, isolation, physical distancing and hygiene. That strategy was learned long before vaccines during the many centuries in which there were no vaccines for anything.

      Those measures had to be taken quickly and crudely and success varied largely due to how quickly they were taken.

      There has been no change in either the virus or the numbers susceptible to it. More refined measures might well be equally effective and more sustainable. But I am not aware of any evidence whatever that control can be maintained with a general return to work and school (before a total re-organization of workplaces, schools and public transport etc).

      The UK has effectively abandoned enforcing the necessary restrictions with a high rate of community transmission. We can expect a faster rise in the rate of infection there – perhaps enough to force a reversal of policy.

      Australia is doing exactly the same thing as the UK but starting from a much lower rate of community transmission. It is close enough to eradication in some States. But for Victoria, NSW and QLD I think it is a deliberate decision not to attempt eradication. The result I expect is a much more gradual increase in the infection rate than the UK, with less danger of it overwhelming the hospitals and therefore less hope of it being reversed quickly (unless we do learn from the experience of others, which is still possible).

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