Coronavirus-Update #27: "Handy-Apps können eine Perspektive bieten" | NDR Podcast
May 02, 2020ndr info that
coronavirus
update
s 93 percent of Germans are in favor of restrictions, i.e. distance regulation and staying at home, according to a survey by infratest dimap on the trend in Germany, Germans They are divided on setting up a cell phone application. 47 percent say they would use them and 45 have doubts about data protection. These are the reports from yesterday, today is Friday April 3, 2020. My name is Anja Martini and I am a science journalist at ndr info and we talk. to professor christian drosten, head of virology, every day at the Charité Berlin, hello Mr. Thorsten, hello, I remember at the beginning of thepodcast
we talked very briefly about applications in China and South Korea that evaluate movement data. of mobile phone users to find possible infected people.At that time you said that it was probably difficult in Germany and I agree with you, this situation has now changed, which means that we are now talking about applications that work anonymously via Bluetooth and that are done voluntarily and There is already an initial study from Oxford in which scientists from all over Europe have worked on this study. Read, what do you think? Yes, this is a study from Christa Fraser's group, one of the best in the logic modeler. Figure that the enemy is simply moving much faster, where more information is coming in than was actually known until recently, so It is simply that the scientific literature is providing more and more data that can also be evaluated and then fed into such models.
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coronavirus update 27 handy apps k nnen eine perspektive bieten ndr podcast...
And the beginning of this study is actually made from the observation that there are more and more real descriptions of transmission pairs in the literature and therefore we can better determine the generation time of this infection, i.e. how long does it last? It takes symptoms to symptoms or infection to infection. One refers to the generation time, the other refers to the length of the series from one infection to another and what is really needed is the length of the series, but it is all relatively difficult to determine exactly and that is why they can at least generate a good coin over the generation time and then they can be derived again from the literature and this is how it starts here: 40 transmission pairs are evaluated from the literature and this is used to feed a pre-existing mathematical model to derive certain parameters and derive certain parts of the entire transmission activity, so the zero transfer number, which here has been recalculated with two, which is a relatively low value if you look at what other analyzes have found previously, succumbed to this , in part it can be approximately two and a half away and puts two more exactly.
Now, of course, we have the opportunity to decompose these transmissions into proportions, so the first question asked here of this mathematical model is how high is the proportion of presymptomatic transmissions of symptomatic transmissions, but also of environmental transmissions and of asymptomatic transmissions, that is, asymptomatic means a carrier who never shows symptoms and presymptomatic means, of course, that it is transmitted before the carrier has symptoms, but this carrier can still be found. later because then you develop symptoms and it is important of course you can still identify contact patients later, it is a consideration that is included later in the post, but first of all, these values that arise are pre-symptomatic 0, 9, so a ratio of 0.9 to 2, so the zero value is the transmission of two symptoms in a ratio of 0.8 and then the environmental transmission 0.2 the symptomatic transmission 0.1.
So if you add these four values together, you get back to 2. Yes, if you look at the numbers, First we need to realize that, in general, the proportion of presymptomatic transmission is 46 percent of the total transmission activity, which is a value which we recently discussed a few days ago in another working group of another document, so the person transmits to the infected even before they are sick. The activity is stored ahead of the symptoms in the transmitter. These are, of course, average values that are averaged across many transmitters and then analyzed in a mathematical model. This is memorable because we have two things here that you need to keep in mind.
Think about it. This actually comes from the value 0 of 2. First of all, it is apparently a good message because if we have a level of 2, then we have less transmissions that we have to reduce to reduce it to zero below 1 and thus bring the epidemic to a neutral, but if we now realize, given that 46 percent of all this transmission activity takes place before symptoms, of course it will be very difficult to reduce these transmissions because in reality only symptomatic patients can be isolated and all These considerations are now included in an interesting calculation that now wants to know what can actually be done with certain interventions, i.e. with measures to recognize an identified person, how long it takes to recognize and how many already infected people they have infected during this time . time because 46 of the transmissions occur before the appearance of symptoms and because it still takes some time until after the appearance of symptoms a diagnosis is made and then contacts can be identified and here it plays a very important role, i.e. , this generation calculated time of infection, which actually tells us even if you isolate yourself immediately when symptoms begin.
If you take someone out who is symptomatic from the transmission situation, then not only will they have infected people, but they will also have infected people after they have been infected. By the time the first patient has symptoms, they are already infected again and possibly have already infected people again and are just starting to do so. So you get to the beginning of your infectivity and you're just starting to infect people again and they actually looked at something like that in the Munich persecution case study and they surprised us, but now there's basically quantitative evidence of the whole thing, also backed up with numbers and data that this really happens and now in this study a very interesting calculation is made. about the possibilities of intervention and what the study really shows is that a simple identification of cases and contact tracing is too late because everything depends simply on recognizing a symptomatic patient and it really depends on the last day. about the fact that a symptomatic patient has no symptoms for a whole time before they are tested and then the test comes and then the chain of reporting starts, then the health department has to come and ask who they had contact with , then these contacts are identified at some point and it all takes so long that, according to these latest calculations, most of the time is needed to get the patients out.
In other words, what is calculated here is also formally very correct and very solid according to the latest figures. What is calculated is that this can be done from a certain point in the epidemic with specific diagnoses, case tracking and isolation of contacts. You cannot stop this epidemic, that is no longer possible and what, of course, can be done to stop said epidemic is that you simply do a lockdown, then you no longer have to continue with the cases, then everyone is at home and, Of course, you can do a combination of measures where you say there is a lockdown that is a little bit softer and includes something like a ban. on meetings, something like that is open right now, exactly more case processing measures, but also that and now there are calculations here that say there are certain efficiencies here.
You can reduce the transmission rates by a certain factor, but the measures always only have limited efficiency and these limited efficiencies are taken into account here and then you come to the conclusion that this combination of measures cannot actually stop it, then it is does something else. Something else is taken into account and that would be the passage of time that will be taken into account. You do it when you use an app like this and here you think of a hypothetical app and this app can record these symptoms at the onset of the symptoms so you just type on your cell phone: Now I have symptoms So check that and then the app says OK, I already sent your data to the laboratory, which means that the application can already register for laboratory diagnosis and in principle you can be diagnosed immediately, so the application solves the diagnosis process and then of course the Information about this diagnosis comes out if it is positive with 1 and at that point the app can start tracking who you were with and what other cell phones, so of course you can also tell how long you were in contact and so on. so that's exactly what these
apps
are supposed to do, then track over time who you were in contact with, which operator of another cell phone, and then these operators of the other cell phone are informed that they were in the infectious state in The moment patient comes into contact with this patient, this means that the spread of the virus is really too fast for scientists working without an app and if you had an app you could track the spread of the virus more quickly.That's the question that's being asked here in this study, what would it be like if we had this speed and we could also store it with parameters in a mathematical model and then you did it, then you assumed okay, if you have an application like that, how much How long does it last? it takes, for example, until the diagnosis comes, how long does it take from the diagnosis to the information about possible contacts and the information you have to stay home now So, in principle, what the health department does So, in principle, that is what the health department's work is in parts of this application transfer and the issue is an information effort that the health department is doing and all of these parameters have been entered into the model and are you can briefly say if the epidemics developed as they did in the beginning where with this speed of time then it would be something like this 1 60 percent of case identifications are successfully defended through the application.
It should be made clear that perhaps if 60 percent of the population participated, they would install such an application and on the other hand, about 60 percent of those who are told to stay home would actually do so. Stay home, then you could reduce it to zero below 1. That's amazing and now there are some restrictions on that. In reality, the speed of spread is now faster, especially in Europe, than at the beginning in Hahn. This is undoubtedly due to several reasons: demographic density, population behavior, but also the degree of progression of the infection, which, of course, makes it even more difficult. so actually a higher degree of cooperation from the population is needed, but exactly more than 70 percent, but it is achievable, so it is an achievable goal with this type of applications to simply overcome this inevitable delay in the presentation activity reporting and communicating essential information. were in contact with an infected person.
You should now get tested to communicate this essential information and the time you spend there. Profits that would actually bring in much more or almost the same as a real block according to this mathematical model and then there are a few chain effects and some gambling options. One possibility, for example, could say in a high incidence situation In a place where there is a very dense epidemic or at a time where there is a wave of infections, you could even bring more speed to the entire system by saying that we will leave this story of try now, we'll reschedule it from now on and say no more, if I check I have symptoms, then the app doesn't tell me, okay?
I already registered it at the lab to get tested, so the app says "Okay", now we see it as positive. Exactly everyone who has symptoms is now defined as positive. Without a test, this is, of course, an intervention measure in which this criterion is stricter and then, of course, and this is an interesting consequence effect, then, of course, all of this person's contacts in the last days with this infected person are immediately defined as actual contacts. So the condition is not established first: the laboratory test must first be positive and then this app goes to all the contacts and tells them: be careful, be careful with the symptoms, but this happens immediately and of course, they can make the criteria stricter again for these contacts, so if they then give a now I have symptoms, so they let me know and now I have symptoms too.
The app no longer said please go get a lab test, but then the app said again that now we have to consider you positive and that you haveyou go home. quarantine So that means that you even have the possibility of an intervention, for example by the health authorities, changing the reaction of said application for a limited time or place, which in reality would be an intervention measure similar to what sometimes you listen in public. It is currently discussed that such lockdown measures are being increased and reduced again as part of a long epidemic that must somehow be managed and overcome.
Instead, you could and that is just a thought game that is stimulated here with this article. Instead, you could also use the sensitivity of such a thing. Just modify the application and then you have the option to make said intervention measure sometimes stronger and sometimes weaker and of course you should say that you could also combine said application for example through others. General circumstances that reduce the transmission of infection, such as the use of masks, and that, of course, is not included here because we do not all know exactly to what extent the use of masks could reduce overall transmission activity if everyone wore a mask.
There are no numerical estimates, but there are. It is conceivable that this combination of a mask when everyone in society wears it has an effect, that this effect adds to such a finely controlled application and I think that is a real perspective on this. At the moment, of course, there is already some desperation in the debate in society about how to get out of these measures and what we do next, and I must say that I am really fascinated by the idea that an app like this could be used, especially if a lot of people participated.
An instrument would have to achieve a completely different degree of precision in control and could say that normal life can continue, there is no general lockdown, companies can function, schools can teach, everything can work, but not for everyone at all. moment, but at some point there will be a time when you have this message on your mobile phone: please go into quarantine at home if you could show it now and the employer would say well, that's right, at home. quarantine this week, so I think it's a very interesting way of thinking, at least one that you can't say no to.
If the Chancellor said yes, they would say yes and about 47 percent of Germans so far would say yes, as would such an app because it is also anonymous in Germany, so we will wait and see what happens in the coming days and weeks in terms of the application. There is another study that we have to analyze and it is about a medicine that we already have. We talked about, namely, chloroquine, an anti-malarial drug that has now developed resistance and is therefore no longer used as frequently and we have talked about a study that I still remember very well from France and they criticized the design of the study a bit at the time.
There is a new study coming from China. What do you say about this study? Well, of course, chloroquine is still in the discussion and that's actually the case. At the time there was a small study from France that I criticized quite clearly. its design and at the end I said that you cannot learn from this study. We don't know now if it works or not because it's just the basic design of this study. So it wasn't even possible to say exactly if the infection time was the same in the study group compared to the control group and now we have a more recent study from China that has also been published and is based on 62 patients in total , so that is always the case. very small study, but this time at least they were randomized and distributed into two groups according to a random generator when the patient was admitted and these are mainly mild cases that are positive by PCR, that is, confirmed by laboratory and who have initial signs of infection on the CT scan So you can already see in the lungs that something is happening and that is also normal, even in mild cases at the beginning, you can see something relatively early on the CT scan on the CT scan and they have no factors that contraindicate the administration of chloroquine, then when you say "They are not allowed to have a bathroom queen, so they do not have retinal diseases, or heart rhythm diseases, or liver or kidney diseases.
You can see which areas have chloroquine ". Everything that has side effects, specifically in these organs, that is really, they are serious side effects and they have. Then you treat one part with queen bleach and another part that you haven't treated and what you find is that the pneumonia in the untreated group improves in 17 out of 31 cases after a week and the lungs show signs of inflammation and that's a combination like the cough and then, but also CT imaging improved in 25 of 31 in the treatment group, so that's enough to say it's a relevant difference. The pneumonia improved more quickly in the treatment group, which is very encouraging now.
Of course, it must be said that it is not exactly known whether this study is a bit small or whether the groups are really composed. The same because here it is also the same again, we have that effect again, we have a larger number of people in the obstruction weighing group Patients with fever and also a slightly larger number of patients with cough at the beginning and that is not This is not It necessarily means that the chloroquine group is a group that has worse initial conditions, but that can also mean, and this study unfortunately now does not say exactly how.
The other study may also mean that chloroquine patients are simply a little further along in their time course. We found that this is not the case here and I really wonder why this is not recorded because we know this from patients, so we will still wait here for larger studies. So we can't say based on this study, Eurogreen is at least a partial solution. Based on these studies, we can say that if chloroquine is a solution, then it is a weak solution. That is clear, so there is not much to be gained by giving plock Vienna, but it could be.
Interestingly, this is the case for mild and therefore also early patients, which is why the early administration of a medication from this guy and this could also be innovative for them. In the future, we should also look at other drugs a little earlier in clinical studies and not wait so much until patients practically have to go to the intensive care unit, but simply have to realize that patients with this disease almost all are mild in the first week. I don't know that in the second week they can get worse and now you have the opportunity in the first week to do something to prevent that, even if these preventive measures can have side effects, that is the big dilemma in these clinical studies that you have to give. something at a time when the patient says why, actually, I feel very good when we talk about the issue of protection, so now we are talking about medications, vaccines, we are talking about not going out, but there are many people who also question We can always do more, for example we can do something for our immune system and strengthen it, maybe vitamin C, vitamin D.
Do you have an idea? Go for a run, of course. It's always good to have a good immune system and of course it's always good physically to be fit and it's certainly not the case that you will get infected while running in the park just because you pass other people so you certainly shouldn't worry. about going out and going for a run. I think I can recommend that, but that's it. So it's also about taking some things, some vitamins, there may be scientific evidence here and there, but that's not my area of research. I'm not familiar with it at all and I've never heard of there being a revolutionary effect anywhere.
So in the context of an ongoing infection epidemic, one would say that we specifically recommend what can be said is that one should stay away. of people who could be infected and who would be in a situation like we have now with a contact ban, you have to think for yourself that it is all the people you meet, for example, while shopping or something, and there is this standard in the USA that says six-week sessions, that is, six feet of distance and six seconds of contact duration. You should take it as a standard to maintain this minimum distance and not be close to someone for too long. way of thinking when you move in normal public if you follow this hypothesis that you are directly infected by someone and you want to stay away from him today is Friday, let's take a look at this week there was some news about the corona virus that surprised you, bothered you or Maybe you were happy, so that's all.
I have so many different impressions coming to me, so what worries me more and more and also stresses me out is when I see the consequences of these current lockdown measures. Of course, starting with the economy, with what is happening to small businesses in particular, that is absolutely terrible and of course we have to get out of these measures, there are studies that I see such as the one on the cell phone application that really are rays of hope . and they are also mental models in which you can say yes, now we have to think positively about the fact that we are all together.
Let's go in this direction and think about smarter measures that can actually be implemented and that, by the way, can also be transferred to poor countries where lockdown doesn't work that way but everyone still has a cell phone in their pocket. Of course, we have to think about it and look exemplary, but then there are other aspects where I can just shake my head, since we actually already know quite a bit, but the same misinformation is spread over and over again; For example, I just read again in an American newspaper that 30 percent of PCR diagnoses are false negatives and exactly this report came from China a few years ago. weeks ago and we know exactly why the PCR diagnosis of the throat is normal after the first week it is no longer positive, we already know exactly that and why it spreads.
Such simple knowledge is not better, especially in times like these, when the newspapers are completely occupied with that content and why that information is given again in the middle of such an epidemic and, by the way, it does not only come from the newspapers, but which also reaches part of the doctors who simply do not know this, who have not faced it, who then have this experience themselves, 30 percent can only be diagnosed based on feelings, but you don't even know that with a smear of throat in patients admitted late to hospital, also in the wrong group That often perplexes me and there are many other impressions.
Yesterday, for example, on a television program there was a compilation of children who contacted their grandparents through videos and told them how much they missed them. That, of course, moved me. In our case it is also the same at home and yes, they are just impressions that I always turn into myself to think, okay, now we have to think about the future, we have to visualize and discuss things like this, like this with the applications for cell phones and all that You can do and achieve anything with it, Mr. Thorsten, thank you very much for today and I wish you a great weekend.
As always, you can find this
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and next to the interviews with christian drosten you will also find the scripts and source references. Have fun reading the ceiling. My name is on the martini and I thank you for listening. Have a good weekend and see you soon. the corona virus updates a ndr info podcastIf you have any copyright issue, please Contact