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  • 1.  CORONAVIRUS IN EUROPE

    Posted 03-14-2020 12:07
    It seems that at least two countries in Europe (UK and Germany) are going to accept a fast diffusion of the Coronavirus allowing it to rapidly reach its peak based on the confidence that most infected will survive thus getting an immunization by direct experience of the disease instead of the use of a still non-existent vaccine. I fear this  strategy would be disastrous for the human kind at large because of the viral pneumonia that would hit around 20% of infected (rough number taken from media news). For instance, Germany declares that they would allow 70% of the population to be infected. Now, 20% of 70% of German overall population would result in millions of patients hit by viral pneumonia. In fact German population is around 80 millions, therefore infected would be 56 millions and hit by viral pneumonia would be more than 11 millions.Taking into account that the rapidity of the peak would create so many pneumonia hit people in a few months, the question is where they would find so many hospital beds for so many patients?
    In my opinion, all would die in their homes where they would infect all relatives including children. For comparison, Italy reached around 20,000 infected now and they say that hospitals find it difficult to find additional beds for the new pneumonia hit people. Millions are absolutely out of the case. 
    This foolish way of doing risks to drive the whole of mankind into problems and to make efforts done by responsible countries useless. 
    I know that we as statisticians have no power in this case. However, just making those consideration to circulate in our community could help in alarming incompetent politician who seem to accept the human kind complete destruction.


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    [Ulderico] [Santarelli]
    [Las Vegas][Nevada]
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  • 2.  RE: CORONAVIRUS IN EUROPE

    Posted 03-14-2020 19:29

    I can only speak for Germany, where I live. You have misunderstood the situation: the 70% was never meant as a strategy - nobody wants to get it over with by infecting 70% of the population quickly. It's a prediction for the long run, because experts no longer expect it to be possible to eliminate the virus. However, strong efforts are now made to slow done growth rates - most provinces have ordered schools and universities to close for the next few weeks (at least), the capital (where I live) has closed much of its public life just now including pubs, gyms, or church service, for example. People in the entire country have been asked ot avoid unnecessary personal contact. Unfortunately, not everybody has embraced the necessity of those measures yet, which means that there are still people who lack the awareness that social distancing is urgently required for protecting the vulnerable members of the population. The article shared by Tim Hesterberg in the other post can certainly help to convince people with an affinity for science.

    Besides trying to slow down the epidemic, hospitals have cancelled projectable surgery in order to free capacity for the expected severe corona cases. We can only hope that the measures do not come too late, and that situations as bad as in northern Italy can be avoided.



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    Ulrike Groemping
    BHT Berlin
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  • 3.  RE: CORONAVIRUS IN EUROPE

    Posted 03-14-2020 20:39
    the peak of 70% is possible only if you do nothing. In fact any action, like restrictions in trips, etc. contributes to two things
    1. delay of the peak some months forward
    2. lower of the peak to a reasonable height compatible with the Health Care system of the country. 
    This can be confirmed by some epidemiologist with experience of models. One accepts the delay, therefore a longer time of recovery, because it lowers the peak. In practice, if you act you will have less stress in the system because infections grow slowly and the simultaneous demand in the millions is avoided. 
    Therefore, talking of 70% of infections is synonymous of doing nothing. I may be in agreement with you that the phrase has been probably said with a different meaning, like the risk of reaching such a monumental incidence of the disease. However the simultaneous and more neat phrase of Cameron who said "many loved ones will die prematurely" should have triggered a German comment, like that for Germany this would never happen. 
     


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    [Ulderico] [Santarelli]
    [Las Vegas][Nevada]
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  • 4.  RE: CORONAVIRUS IN EUROPE

    Posted 03-15-2020 11:38
    I would like to know the origin of the number 70% in Frau Merkel's projection. I think I know the answer.

    R0 is the basic reproduction number: the average number of infections caused by a random infected patient. The larger R0 is, the more widespread the outbreak will be.

    The expression 1-1/R0 is important in epidemiology. Originally, I guessed that this might signify the fraction of the susceptible population that will become infected. That is not so. Actually, it signifies the fraction of the susceptible population that must be vaccinated to prevent further spread of the disease.

    I have seen estimates for the coronavirus R0 ranging between 1.4 and 4.0. The median value from one meta-analysis I saw was about 2.4. If we round up to 2.5, then 1-1/R0 = 60%. It would take R0 ~ 3.3 to get 1-1/R0 ~ 70%.

    Even if 1-1/R0 ~ 70%, that is not a forecast of the infection rate for the population. It is just the fraction of the population that must be vaccinated to stop the epidemic.

    One other critical point: R0 is not constant! It decreases by containment, quarantine, social distancing, and apparently weather. Warm, moist weather seems to inhibit the ability of respiratory viruses to spread. The infection rate and death rate from coronavirus in the densely populated but warm tropical countries is quite low. Therefore I hope that northern countries will see relief from the pandemic during summer, only to return next fall, when we should be closer to a vaccine.

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    Hal Switkay
    United States
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  • 5.  RE: CORONAVIRUS IN EUROPE

    Posted 03-15-2020 12:31
    I don't think that Merkel's 70% should be interpreted as a projection - it was a sort of worst-case percentage of vaccinated needed for herd immunity, like you wrote. And as long as there is no vaccine, and one assumes past infection to act like a vaccine, this percentage is an estimate for the number of people needed to have been infected until the epidemic stops. But of course, action is hoped to improve the situation. I hope that you are right about summer; so far, not all experts seem to be confident that summer will give us a break. And we will almost certainly have to handle the next winter without a vaccine (but perhaps at least with better drugs for treatment).

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    Ulrike Groemping
    BHT Berlin
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  • 6.  RE: CORONAVIRUS IN EUROPE

    Posted 03-15-2020 14:35
    one has to look also at the media distortions. Of course, they oversimplify and contribute to the overall confusion. For instance, The Economist in the issue of March 14th writes "In Germany, Angela Merkel said that 60-70% of the country's population may contract the disease at some point". Today's FOX NEWS informed us that "Italy and Spain locked down their entire countries". No mention of actions in France, Germany and minor countries as well. Readers lack information about what happens there. 
    My point is the following: "doing nothing will overwhelm the Health Care system Capacity". This morning, in a press conference Cuomo told NY State Residents that ventilators will not be enough above a threshold of patients needing ICU (Intensive Care Unit). Ventilators are breathing supports for viral pneumonia sick people. They are scarce, costly and difficult to buy because factories are overwhelmed by orders from China and Italy. The terrible thing that can happen is suddenly finding that you need 1 million ventilators and the production capacity can only  provide you with 1 thousand in 5 months!!
    Keeping the peak as low as possible make things easier in the hope of a full extinction of the problem due to:
    1. the appearance of remedies. For instance, in Italy they found that an anti-arthritic drug proves effective at a good extent. 
    2. the arrival of vaccines. They are in sight in may be twelve months. If you reach that point with a limited number of cases, because you were able to curb the growth curve, the immunization would be by vaccination and not by survival to the disease. They say that people can repeatedly be hit by the virus. Therefore, the immunization through survival seems to be more of a dream than reality
    3. hopefully, the hot season could help in curbing the virus.
    Therefore, the problem is fighting strongly in the short term in the hope that in the mid term the quoted factors will help and a  long term victory is possible.

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    [Ulderico] [Santarelli]
    [Las Vegas][Nevada]
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  • 7.  RE: CORONAVIRUS IN EUROPE

    Posted 03-16-2020 09:41

    one has to look also at the media distortions. Of course, they oversimplify and contribute to the overall confusion. For instance, The Economist in the issue of March 14th writes "In Germany, Angela Merkel said that 60-70% of the country's population may contract the disease at some point".
    Ulderico Santarelli,  03-15-2020 14:35
    Merkel said, in German:

    «Wenn das Virus da ist und noch keine Immunität der Bevölkerung gegenüber diesem Virus vorliegt, keine Impfmöglichkeiten existieren, auch noch keine Therapiemöglichkeiten, dass dann ein hoher Prozentsatz – Experten sagen 60 bis 70 Prozent  – der Bevölkerung infiziert werden.»

    In English, this translates as

    "If the virus is there, and there is still no immunity from the population to this virus, with no vaccination options, and still no therapeutic options, then a high percentage - experts say 60 to 70 percent - of the population will be infected."

    Note the if clause.  Merkel was describing the worst case to emphasize the need to develop vaccines and therapies.  (I also massaged Google Translate's translation to make it flow better in English.)

    In an entirely different context, an if clause was removed from something I wrote to make it sound as though I had intended something terrible, which was not my intent at all.

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    Chuck Coleman
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  • 8.  RE: CORONAVIRUS IN EUROPE

    Posted 03-16-2020 10:37
    here is a very interesting discussion about mistakes one can do in setting up a response. The most important point is, in my opinion, assessing the Hospital Capacity for this specific pandemic. Even in US the pandemic could exhaust Heath Care System's Capacity.

    https://www.vox.com/2020/3/16/21181025/coronavirus-covid-19-us-testing-pandemic


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    [Ulderico] [Santarelli]
    [Las Vegas][Nevada]
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