From containment measures to the phantom peak, through vaccines, immunity, prevention, lethality, epidemic history and intensive care, some of the key things we know about Covid-19. Or at least that we know we don’t know.
Putting in order all that we know today about the coronavirus, even if only in an epidemic, scientific and sanitary sense, would mean collecting an infinite amount of material, there are many studies and possible evaluations on what is happening in Italy and the rest of the world.
For this reason, we have collected here a selection of some things that we know but that is perhaps a little less well known, along with others that are famous precisely because it is essential to know them. Without forgetting what, to paraphrase Socrates, the scientific community “knows to don’t know”, that is, those issues on which at the moment we can only suspend judgment.
1. We know: how long does the containment take effect?
Let us assume that on day zero a very effective measure for the containment of coronavirus infection will be taken on a certain population: after what would we see the effects? Of course, it would be a progressive phenomenon, but it is possible today to give a more than acceptable quantification of this period of time. In fact, we know that the incubation period of Covid-19 is in most cases 4-7 days, with the possibility that it is shorter but also extends to a couple of weeks.
In comparison with the onset of the first symptoms, according to what the Higher Institute of Health has estimated, in the most serious cases that can then have a fatal outcome, an average of 4 days pass before the hospital admission and another 4 days before the eventual death. Therefore, if we were to observe a deviation in the epidemic curve of deaths, we could expect the most significant effect to begin around two weeks from day zero, although of course it would be a phenomenon spread over time and that lasts at least the whole third week (our lockdown, for the record, began with the decree Dpcm of March 9).
Of course, this time could be a bit reduced in an ideal world where we could lock down all the people every day, but in reality, we know very well that, indeed, there are many people who contract the virus and are never diagnosed, and therefore only hospitalizations in intensive care and deaths are data that guarantee a relative (but not absolute) statistical reliability. What is certain, in any case, is that the effects of any containment measures are invisible at least for the first 10 days.