A mathematical model and forecast for the coronavirus disease COVID-19 in France

(A.B. Alyokhin, B.V. Burkynskyi, A.N. Grabovoi, V.A, Dilenko, N.I. Khumarova)

Forecast Monitor

03/09/2020. No F-171

In the previous forecast monitor of the coronavirus epidemic in France, which published today (see https://www.facebook.com/ab.alyokhin/posts/177709390538631), using the example of the previous forecast, we showed what a departure from positive trends due to the uncontrolled weakening of quarantine.

In this monitor, using the updated forecast as an example, we will show what trends of recent weeks can lead to the end of the forecast period, if cardinal measures are not taking to curb the spread of the coronavirus. Thus, when developing this forecast, we deliberately reject any elements of the scenario approach, which provides for the adoption of assumptions such as “if — then”, except for the only one — “if nothing is done, what will be so.”

How it will be (how it can be), the diagrams in Fig. 1–13.

The diagrams in Fig. 1–4 indicate:

- actual trajectories of the main indicators of the coronavirus epidemic in France for the entire observation period;

- calculated trajectories of these indicators for a lead period of 10 days;

- boundaries of the confidence intervals of forecasts (ranges of possible deviations of a point forecast with a significance level of p = 0.01).

The diagrams in Fig. 5–6, similar to the diagrams in Fig. 1–2 are given:

- actual trajectories of changes in the corresponding indicators of the coronavirus epidemic in France for the entire observation period;

- calculated trajectories of these indicators for a 30-day forecasting period;

- actual (at the time of the forecast) and forecast (at the end of the 30-day forecast period) values of the corresponding indicators.

These charts, therefore, indicate the projected extent of the epidemic at the end of the 30-day lead-in period, with current trends continuing.

The diagrams in Fig. 7–10 are given:

- actual trajectories of changes in the daily indicators of the coronavirus epidemic in France for the entire observation period;

- calculated trajectories of these indicators for a 10-day forecasting period;

- boundaries of the confidence intervals of the 10-day forecast (p = 0.3).

Diagrams Fig. 11–13 contain:

- 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 a 30-day forecast period.

The forecast calculations show that if decisive measures are not taking to limit the spread of coronavirus, then the epidemic in France will go on a second round at about the same scale. We must assume that the governments and citizens of this country have a better idea of what it will mean to them. Therefore, not all these arguments directed towards France. First of all, towards the government and citizens of Ukraine, which so far demonstrate a similar attitude to the problem.

Sources of statistical data:

https://www.worldometers.info/coronavirus/#countries

Our materials also:

https://t.me/mathmodelcovid19

Accuracy of our forecasts:

Publications on case fatality rates and progress indicator