A mathematical model and forecast for the coronavirus disease COVID-19 in Italy
(A.B. Alyokhin, B.V. Burkynskyi, A.N. Grabovoi, V.A, Dilenko, N.I. Khumarova)
31/10/2020. No F-250.
Yesterday (see https://www.facebook.com/ab.alyokhin/posts/193752235601013), we analyzed the evolution of the COVID-19 epidemic in Italy based on a comparison of the actual data and a 39-day forecast developed and published on September 21, 2020. (see https://www.facebook.com/ab.alyokhin/posts/182735653369338).
Calibrating the model using statistical data, including October 30, we confirmed our main assumptions. Over the past forecast period, only the spread of the coronavirus has significantly increased in Italy. At the same time, the mortality rate remained practically unchanged. The time lag between the moment of illness and recovery slightly reduced. Other parameters of the mathematical model did not require any adjustment.
Thus, all the features of the COVID-19 epidemic development in Italy noted in yesterday’s monitor are solely due to the weakening of quarantine requirements.
The next forecast of the COVID-19 epidemic development in Italy essentially extrapolates the latest trends for a forecast 10 and 30-day period (see Fig. 1–13).
The diagrams in Fig. 1–4 indicate:
- actual trajectories of the main cumulative indicators of the COVID-19 epidemic in Italy for the entire observation period;
- calculated trajectories of these indicators for the same period, as well as for a 10-day forecasting period;
- boundaries of the confidence intervals of a point 10-day forecast with a significance level of p = 0.01 (in Fig. 1–2, the boundaries of the confidence interval are hidden due to overlapping on the main graphs).
Diagrams Fig. 5–6 differ from the diagrams in Fig. 1–2 only because they present a 30-day forecast without confidence intervals, but with the current and forecast values of the corresponding indicators at the end of the forecasting period.
The diagrams in Fig. 7–10 characterize:
- actual trajectories of changes in the daily indicators of the coronavirus epidemic in Italy for the entire observation period;
- calculated trajectories of these indicators for the same period, as well as a 10-day forecast period;
- boundaries of the confidence intervals (p = 0.05), corresponding to the 10-day forecast.
Diagrams Fig. 11–13 reflect:
- actual trajectories of lethality indicators I (TC), I (CC) and the IP progress indicator for the entire observation period;
- calculated trajectories of the indicated indicators for the same period, as well as for a 30-day forecast period.
Thus, the forecast, based on the available statistical data, does not imply an active counteraction to the spread of coronavirus in the near-term outlook, thus demonstrating the possible scale of the consequences of such a scenario for the development of the epidemiological situation in Italy.
Sources of statistical data:
Our materials also:
Accuracy of our forecasts:
Publications on case fatality rates and progress indicator