Estimates of R0

Robust estimates of the case fatality rate of COVID-19 put it under one per cent. To provide some context, the Black Death is said to have killed 60 percent of the European population. The Spanish flu killed 50 million people with a death rate of 10 per cent. HIV/AIDS has killed 35 million people. As many as 575,000 people could have died from H1N1 in its first year of circulation. Seasonal flu kills less than one percent of infected individuals. The COVID-19 death rate appears to be concentrated amongst elderly and immuno-compromised individuals and skewed somewhat towards males.

COVID-19 is highly contagious. Here the important statistic is known as R0 (R-naught). Writing in The Conversation University of Michigan Professor of Epidemiology Joseph Eisenberg describes R0 as follows “the number of cases, on average, an infected person will cause during their infectious period”. So if disease had an R0 of 2, then each infected person would in turn infect two other people. Professor Eisenberg reports that current estimates for the COVID-19 R0 is between 1.5 and 3.5. To provide some context, the R0 for H1N1 is estimated to be between 1.46 and 1.48, the R0 for the seasonal flu is between 2 and 3.

The thing to understand is that R0 is not a constant – it is time-varying. The Centre for the Mathematical Modelling of Infectious Diseases at the London School of Hygiene & Tropical Medicine has estimated R0 for several countries – including Australia. (HT: Marginal Revolution)

If this estimate is correct – the ‘war’ against COVID-19 was won in Australia nearly 3 weeks ago.

This entry was posted in COVID-19, Oppressive government. Bookmark the permalink.

44 Responses to Estimates of R0

  1. Robber Baron

    But the war against freedom and capitalism continues.

  2. feelthebern

    We better nuke the economy from orbit.
    It’s the only way to be sure.

  3. We better nuke the economy from orbit.

    We have renewables to do that as a full blown (no pun intended) ground offensive.

  4. John A

    If this estimate is correct – the ‘war’ against COVID-19 was won in Australia nearly 3 weeks ago.

    When Diktator Dan of Viktoriastan was starting to talk about Stage 4 restrictions.

    Robber Baron is correct.

  5. Nato

    Do you think that this will fall off the radar, or amplify the interest around every suspected patient? I reckon you nailed it worth your insights little while ago of big government types managing the statistics to reach further.

  6. nfw

    No, we have to fight it ’til the last virus of any dirty disgusting racist fascist China disease has been eliminated, otherwise Scott Morrison won’t be the world’s saviour and the SS Services might have to go back to doing their real jobs instead of the owners of this country getting on with simple pleasures such as being a park, swimming in the ocean or driving a car to see family and friends. You know, just like all the Chinese who left Australia to go to Wuhan Virus Flu central in late January for their New Year and then came back. Still waiting for the AFP to “prosecute” those shelf strippers and expel daigou. This is straight out of the Yes Minister episode about dioxin.

  7. nfw

    Given those curves and data it would seem the politicians and highly productive public servants were late, again, as ever. No wonder none of them are being laid off or taking pay cuts.

  8. JohnJJJ

    Seems more and more evidence that, like TB, the breath is the primary means of transmission. When combined with viral loading it explains the results of Professor Hendrik Streeck’s work in Germany.

  9. Farmer Gez

    Shhh….Don’t tell Numbers.
    He’s planning to fight this virus for decades.

  10. Rohan

    Wow, the according to the graph of known cases and the likely infection date for Oz, that puts that the tail end of the error bar when the Ruby Princess docked and passengers were released on the 18th March.

    Well done Hazzard, you are a prime dickhead. About a third of all known cases can be attributed to your incompetence.

  11. I understand that Sweden (with a smaller population than Oz), that didn’t impose any restrictions and continued to party on, has now experienced over 900 deaths. They’ve only just started.

    So I’m not sure who is right or wrong, Australia’s somewhat conservative government or Sweden’s full blown Leftist government?

  12. max

    apparantly 10 times flu.

    for America that would be ;

    50 000X 10 = 500 000

    amount spend 2 trillion/ 500 000 = 400 000

  13. max

    just check that numbers my math is bad

  14. max
    #3410903, posted on April 14, 2020 at 2:07 pm

    just check that numbers my math is bad

    Add another zero. It’s 4 million.

  15. Bela Bartok

    The socialists/robber-barrons in power are enjoying their time in the sun way too much for this to be called ‘quits’ anytime soon, despite the graph indicating they can.

    Our health officials: will the quisling press ever hold them accountable for their gross distortions around the number of deaths? Of course not – if there were any decent journalists, they’d have pilloried Tim Flannery but he gets away scot-free. So will these Health clowns. They’re even saying the end of winter is when we should ease isolation.

    And why waste a disaster/opportunity like this to bash Trump and complain about his late closure/that was too early/that was racist… there’s sport to be had!

  16. max

    Well price to live — I can tell you if I work next 100 years I can not make that kind of money

  17. ryki

    I understand that Sweden (with a smaller population than Oz), that didn’t impose any restrictions and continued to party on, has now experienced over 900 deaths. They’ve only just started

    Virus deaths are meaningless because every country has different ways to record it. Italy and New York and the UK are calling anybody who fell out of a plane without a parachute as COVID deaths. We aren’t.

    You have to look at all cause deaths. If they have spiked then you just might be in a pandemic. If not, then you’re not.

    In Sweden, all cause deaths are perfectly average at the moment. There is no noticeable effect – if any – of COVID deaths on Swedish data.

    By the way, while I don’t have a problem with the OP graph, what about the data I have provided which shows that the virus *never* actually spread in any country?

    That is, the ratio of positive cases/negative cases never appeared to increase significantly in any country. The entire basis for the appearance that COVID cases were increasing was purely a function of increased testing.

  18. Tim Neilson

    bemused
    #3410894, posted on April 14, 2020 at 1:56 pm

    The stats that came up quickest on search say that in a recent fairly benign NH winter Sweden had over 500 flu deaths.

    So they might well argue that this has been just like a somewhat more severe than normal flu season.

    When you say “they’ve only just started” do you mean restrictions? That might make sense – it’s the start of warmer weather, so do a short very sharp campaign of comparative social isolation to crush the thing, then let the warmer weather do the rest.

  19. I realise that the reporting of Wuhan Flu deaths is quite erratic and prone to being exaggerated (everywhere), but I was just wondering whether the devil may care attitude of Sweden was such a good thing. It seems they were experimenting with a different approach to the rest of the world. Very embarrassing if it turns out to be a flawed approach.

  20. Tim Neilson

    Very embarrassing if it turns out to be a flawed approach.

    True, true,…

    But almost as embarrassing for, e.g., ScoMo, the Hunchback of Spring Street, Pony Girl et. al. if Sweden turns out to have got it right.

  21. Iampeter

    If this estimate is correct – the ‘war’ against COVID-19 was won in Australia nearly 3 weeks ago.

    If these numbers are correct – the “war” against COVID-19 should never have even taken place.

    But the war against freedom and capitalism continues.

    But let me guess, you’re a Trump supporter?

  22. Biota

    All of the comment about the restrictions being a cover for insidious totalitarianism is based on hindsight. No one knew what was going to occur when the virus first arrived; even its identity wasn’t known. So who among those conspiracy theorists can say what course they would have chosen at the outset had they the responsibility. As bemused notes, Sweden is a good comparative model so lets see how they get along in the end. I suspect there is more hindsight to come yet.

  23. Harpo of Wolli Creek

    Bemused, why on earth would you only compare Sweden with Australia. If you go to worldometer you will see immediately that the UK, Italy, France, Spain, Belgium and the Netherlands all have death rates per million that are many multiples of Sweden’s. Additionally, it would be interesting to see where in Sweden these deaths are occurring-if in Malmo it may be a reflection of the demographics of that area rather than anyoverall Swedish problem.

  24. Struth

    Just get up and get out of your houses, they can’t arrest everybody, they’d have to put you in home detention……………..oh wait…………..
    I’m out and about going for a drive checking the lay of the land, for no reason at all.
    Fuck ’em.
    If you are a free people start acting like it.

  25. But almost as embarrassing for, e.g., ScoMo, the Hunchback of Spring Street, Pony Girl et. al. if Sweden turns out to have got it right.

    I think the answer is somewhere in the middle, at a balance point. But when do politicians ever understand that, especially with esteemed ‘experts’ always on hand.

  26. Bemused, why on earth would you only compare Sweden with Australia.

    I was merely pointing out the differing approach and how that approach might be falling apart.

  27. Beachcomber

    But almost as embarrassing for, e.g., ScoMo, the Hunchback of Spring Street, Pony Girl et. al. if Sweden turns out to have got it right.

    According to Covid Doomsday Cult Sweden Should Be Drowning in Bodies. It’s Doing Better Than Lockdown Britain

  28. ryki

    So who among those conspiracy theorists can say what course they would have chosen at the outset had they the responsibility.

    I knew exactly what would happen with 100% certainty. No hindsight heroes here. I knew with 100% certainty that the virus was a) not new; b) not contagious; and c) not pathogenic. I also knew that the only deaths would occur as a result of d) panic; e) medical treatments; and f) economic destruction.

    The course I would have chosen both in hindsight and at the time was to do absolutely nothing except inform everybody in the media (and possibly social media) that drumming up hysteria over a medical crisis could itself be considered a medical emergency and I might just use my “emergency powers” to deem that all media were “non-essential businesses”. The ABC would have been given just one chance and if it failed to report honestly then it would have seen an immediate 100% reduction in funding. Every other business – including mass gatherings – would have been allowed to continue as they saw fit.

    I would have banned all testing because they are 100% worthless but instead every night I would have stood up in front of the country and shown all cause deaths in Australia vs normal deaths. I would have compared these to countries in lockdowns.

    I was merely pointing out the differing approach and how that approach might be falling apart.

    But you miss the point. The only possible means of justifying our actions would be if the counterfactual led to, literally, hundreds of thousands of deaths in Australia. Sweden having a couple more deaths per million population compared to us does not magically make our approach ok. Of all the countries, Sweden is around the mid point. But they are one of the few that won’t have experienced astonishing levels of economic destruction. Their economy has still taken a hit. But it will recover in a year or so. Ours virtually never will. Nor will Italy’s. Nor will Spain’s. Nor will France’s. Nor will the US’s.

  29. Faye

    The models are thumb-suck crap based on non-empirical data. One thing we have learned from the Climate Change hoax, is never believe scientists or experts except, of course, the hallowed few. The rotten ones are proved wrong time after time but the politicians don’t have the backbone to throw them out of our lives.

  30. Biota

    ryki
    #3411050, posted on April 14, 2020 at 4:11 pm
    Genuine question, how did you know?

  31. MACK

    The Hong Kongers do a live R0, which is now well below 1:
    https://covid19.sph.hku.hk/
    40% of their cases have recovered, with only four deaths. And plenty of them have been flouting the rules:
    https://www.channelnewsasia.com/news/asia/hong-kong-residents-rules-covid-19-popular-sites-12635444

  32. slackster

    Good tracking website here with history for the last 10 years for Europe

  33. ryki

    Biota there are actually at least three ways I knew with certainty.

    But let’s start with the very obvious fact that just because researchers had never seen a particular (strain) of virus before doesn’t for a second mean that such a virus has never been harboured by humans before. Well, obvious to me.

    Nobody else asked this question though.

    If you were an explorer in the 16th century and you stumbled across an island in the Indian ocean that wasn’t yet mapped would you conclude that A) the island just sprouted into existence in the last couple of days; or B) it had actually been there a long time it’s just that nobody had crossed this exact path before?

    B right?

    But our Chinese virologists instead went with the absurd A. And it was that decision that has led to this pointless destruction.

  34. Beachcomber

    Biota at 4:23 pm

    ryki – Genuine question, how did you know?

    For me, I didn’t pay much attention at first, but when the CCP and the ABC started insisting that it was an epidemic health crisis I suspected it was a crock of sh*t. When I looked into corona viruses, and at how infections were supposedly being identified, and how deaths were being tallied; I very quickly knew for sure that the plague story was a crock of sh*t.

  35. slackster

    Spam filter blocking the link- shortened here:

    https://bit.ly/3bbQNOw

  36. MACK

    Today’s AFR:
    “One of the government’s top advisers says the key measure of Australia’s COVID-19 infection rate has fallen below one – the point at which the virus begins to fade.
    Melbourne University mathematics professor James McCaw, a co-author of the Doherty Institute epidemiological modelling released last week, said his team had been making estimates of the effective reproduction rate – known as the “Reff” – about twice a week, and was looking to release a public version of the number.
    “There is enough local data now to create a Reff. A fortnight ago we did not have that confidence, but my group’s estimate is it is well under one,” Professor McCaw told The Australian Financial Review.
    “That number is true in each of the states where there is enough data to make an estimate with confidence: NSW, Victoria, Queensland, South Australia and Western Australia.
    “The sooner it is published, the better,” Professor McCaw said.
    He later published graphs showing the data for some states on Twitter.

  37. Biota

    Thanks, I am a research biologist accustomed to hard data rather than supposition or informed guesses. It will be interesting how this all turns out. Meanwhile even though I am >70 yo I am still traveling (by car) and working, but taking all the distancing and hygiene precautions. There’s a heck of a lot of us doing this across all working age groups by my observation.

  38. MACK

    https://twitter.com/j_mccaw/status/1249592269977423879

    The real data show that the R0 was below one in the major states before the shutdown. Meaning most of the economic damage has been completely unnecessary.

  39. old bloke

    The “lockdown” was justified on the grounds of “flattening the curve” which was thought necessary to avoid a rush on critical care beds in Australia’s hospital system. There was no unprecedented demand for extra critical care beds, we are well past the peak in demand for hospital services, and there is no communal spread of the virus to justify continuing this unnecessary economic shutdown.

    End it now.

  40. Matt

    If you’re going to claim robust estimates of CFR around 1%, I suggest not quoting a paper that only analysed data to 25 Feb, when the global death toll was less than 3000 (it’s now over 100,000). More recent studies have the CFR higher than that.
    And R0 for seasonal flu is 1-2, not 2-3.

  41. Dr Faustus

    MACK: The tweeted graphs are ‘effective reproduction’ – not R0.

    Effective Reproduction = R0 multiplied by an estimate of the proportion of the population susceptible to Covid19. At this stage, given no antibody testing, those population estimates For “Reff” are pluck numbers.

  42. Richard B

    The most comprehensive recent figures I’ve seen were from a random sample of 1,000 in a hard hit German suburb called Gangelt. It turned out that many more had been infected and recovered than expected and the fatality rate was reduced from around 2% to 0.37%. This tallies with the early estimates from the Diamond Princess. It also suggests that the majority are immune, at least if not exposed to heavy loads of the infection.
    The study was led by Professor Streeck from Bonn.

  43. Archivist

    Robust estimates of the case fatality rate of COVID-19 put it under one per cent.

    The Lancet article assumes perfect testing.

    The one issue I haven’t seen discussed much (actually, I haven’t seen it discussed anywhere) is the issue of false positives and false negatives. If the tests have even a small, but non-zero, false positive rate, then broad testing will reveal hundreds of thousands of spurious cases, which would be then documented (incorrectly) as asymptomatic cases… when they should be documented as non-cases. I’m not saying that’s what’s going on, but it would explain the disparity between various national rates, and would also explain the disconnect between the rather comforting data and the ‘on the ground’ reports from places like Milan and New York.

Comments are closed.