numbers inform decision making how many kids can be safely in one classroom or how many people should i be allowed to meet with. but with new and changing numbers coming to us every day what's important and how do you keep your head from spinning. with so many statistics associated with the coronavirus pandemic is imposed was give on top of them all or even to understand them well if all these numbers all leaving you know allow us to help you out by explaining a few of the key ones. the 7 day incidence indicates how many people tested positive within one week measured per $100000.00 inhabitants. for example let's assume a city with 129000 inhabitants has this number of positive tests in one week we add

up all the positive test results. and then the 7 day incidence is calculated 48 times 100000 divided 512-1000 inhabitants giving an incidence of 37.2. the number allows you to ascertain the current infection rate in other words how many people are currently infected in a region and since it refers to 100000 inhabitants one can also say so to speak what the percentage of new infections is. of value is considered problematic for a region once it becomes difficult to identify all contacts and infected person has had in germany that is a 7 day incidents above 50. the effective reproduction rate are describes the average number of people an infected person passes the virus on to an r.

value of 2 means that one infected person passes the disease to 2 others meaning the virus spreads exponentially. if the effective reproduction number is less than one the number of new infections decreases. or you can talk incidence of the 7 day incidence offers in initial estimate the reproduction rate gives you an idea of the dynamics how quickly the infection is currently spreading from one person to the next. from i don't mean. the gays fatality rate indicates how many people who tested positive die from or with the virus. if for example one out of 10 people die is the case fatality rate is 10 percent. if we take a look at the latest case fatality rates from different countries we see a very inconsistent picture with the world average hovering around

a case fatality rate of 2.4. if the number is important for considering how threatening the infection is for an individual patient but it also has notable problems on the one hand the number of unreported cases is very important and the number of undetected cases also depends on how much testing is going on in other words you might get a distorted picture if you test very much or very little if you look as if you need to test and that's the problem with many of the key statistics depending on your test capacity the figures change nevertheless the measurements provide valuable information with doctors get in short it's about relative changes and you can see those quite well in these figures. and the goal remains the same all through the pandemic super event healthcare systems from becoming overburdened.

let's speak to in the revolver also who is a mathematician of the frank the institute for advanced studies thanks for joining us maria so many numbers too many for anyone to really keep across so can you help us out here is that one number that we should be paying more attention to the no the other. well there are really many numbers concerning independent nick and care have been many coming across during the months. we are currently paying very much attention to numbers which indicate disagree disease like hospitalization and i.c.u. requirement. so people who are in severe conditions because of disease disease and does are numbers to us which inform us a bit more about. this a very key and health care requirement roger did only numbers concerning the

detection so like 7 days incidents or r.t. number so you say that's what you're currently focusing on that's the number that's most important change of the time. this this change of course we have been tracking down the sensually since the beginning of dependent make it it became quite clear to does a disease that require or might have a seeing severe course and hand up in deaths or require us to healthcare and does is of course an indicator which which is not stable depends very much. on the health care capacity of the country but i believe is less affected. tracking capacities or testing that to the team in the country. so we have all these numbers they are number 7 day incidents and stuff to the general public need to be across these numbers i can understand why governments

decision makers by means of people what about i can we just stay at home and do as we're told without getting caught up in the thickens. well i guess it's probably the 1st time at least since i'm aware of and as surely the 1st time to people became so informed about the meaning of the production number were a even seventy's instance for any disease. those numbers are reported for a number of diseases but usually are kept in in control systems in health care facilities so people who are working wouldn't so now if they went into the community and i guess it was because of making people aware or making people. aware of this a very dependent of their weight credits. but of course and then the number of the numbers as we get to more numbers steadily gets destroyed can make people more confused

a might not know what they are looking at it's there are some indicators like overproduction number or wish which is not like temperature measurement it's depends on under cases that are reported and this are in case of cold feet for sure or not all cases which we have out there you know i suppose misunderstanding the numbers could cause more problems than not knowing the material and i marie above are also thank you so much for bringing us your expertise from the front that institute for advanced studies thank you very much. now is the pasta the program where you get to ask the questions you've been submitting them through our you tube channel so now let's put one of them to ask science correspondent derrick williams. should people who have already had 1000 continue to wear masks. i

answered this question a few months ago in the guidelines haven't really changed but it gets sent in so often that i guess it's it's maybe time for a reminder the short answer is that a lot of aspects of covert 19 immunity are still pretty hazy because people simply haven't been recovering from it long enough to provide solid long term data based on what we've seen so far with the disease people who get infected once do acquire some immunity for a period of time the big problem is we still don't really know how long on average that period is so for some framework it makes sense to look at what we know about other coronaviruses that infects humans and and studies there have revealed that immunity can wane pretty swiftly a number of them convincingly show people can be really infected with some of those pathogens within a year of catching them ones so far there have been

a few dozen documented cases of that also happening with covert 19 but as as proving reinfection is quite a complex challenge the real numbers are almost certainly higher in some of the documented cases the people who got it again showed no symptoms the 2nd time around but but in others they got the disease worse and we still don't know whether they were infectious to others so until we have better data guidelines from health authorities like the c.d.c. recommends that you continue to wear a mask especially in. indoor public spaces until we have more information you should assume that masking up is still an effective way to protect not only others but yourself even if you've had covert 1000 once and recovered from it.

and you can submit a question for derek through you chief of shadow detail we have news now i know we've already thrown a lot of numbers in today's program but bear with us here we have just a couple of more for you because with the vaccine production starting up around the world we asked you to our social media channels if you would take a jab against cobbett 9 teams there the results the largest proportion over 40 percent said they'd rather wait and see before taking a vaccine 38 percent said they offer pads to take the vaccine and around 16 percent said they would not be willing to get immunized against cardiff 90. that was a bad as mentioning that are only just say immunization is the only way to get a grip on the coronavirus pandemic but it seems there is still a fair bit of skepticism around the vaccines we've seen developed in recent months well that's all from this edition of the current 19 special for the latest developments on the corona virus pandemic go to our website d.w.

dot com slash call it 19 until next time take at least a healthy. pick

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