What the model calculations of the TU Vienna and the TU Vienna spin-off dwh predicted a week ago (elektroniknet.de reported) is now coming true: The prescribed reduction of social contacts slows down the spread of disease.
In Austria, most people have followed the recommendations and reduced the number of interpersonal contacts. »Thus, exactly what we calculated for this case a week ago has happened: The number of Covid-19 cases is still rising, but the daily percentage increase has decreased. We are on a good path«, says Niki Popper, CSO and co-founder of dwh.
When the virus started to spread in Austria, the number of confirmed cases doubled every two or 2.5 days. In the last few days, the daily increase has become smaller, now a doubling in the range of four to six days can be expected. This is exactly what the calculation models showed a week ago (see also the report of 19.03.2020 on elektroniknet.de).
Now calculations are still carried out to evaluate the individual measures implemented so far - and also to estimate how and when it will be possible to withdraw the measures. For this purpose, the team of the TU Vienna has now joined forces with colleagues from the Medical University and Gesundheit Österreich. »How quickly this can be done depends on the successes in the near future. The important thing is to test as many people as possible for the virus - what counts in the end are measured figures, not forecasts«, says Popper.
The great unknown: the estimated number of undetected cases
As always, when you simulate such complicated processes on the computer, there are still some unanswered questions. One of them is: How many people are infected with Sars-CoV-2 without knowing it? How high is the dark figure?
»There is, of course, an estimated number of unreported cases. Some research teams have also already tried to estimate this unrecorded figure - which is good, but of course very difficult«, says Niki Popper. The first promising considerations are currently being made by IHS, with which TU Vienna is also cooperating.
However, if significantly more people were infected without symptoms, that might not be bad news. The number of serious cases that have to be treated in hospital is known. A high number of unreported cases would therefore mean that the proportion of serious cases is lower than previously thought. In addition, a high number of unreported cases would mean that the goal of herd immunity would be closer: it might not be so long before a sufficient number of people would be immune to the virus.