COVID-19 in Poland

Information and updates summarized below are a part of scientific article linked below (click paper’s page to download pdf or article title for online MedRxiv).

 

 

Forecasting COVID-19 pandemic in Poland according to government regulations and people behavior.

 

 

 

 

The forecast for Poland of COVID-19 spread concerning various scenarios of people behavior and government regulation.

The primary forecast was prepared including data from the very beginning of COVID-19 pandemic in Poland (4 March 2020) till 22 of May. We demonstrated three potential scenarios regarding different people behavior patterns and protective measures provided by the Polish authorities. Independently of the scenario, the cumulative number of infected will exceed over one million people in a year, although if to maintain the restrictions on a certain level of social distance, the increase would be much slower allowing to avoid depletion of the medical resources. In contrast, if to maintain strict measures provided before the date of 18 May till September, the cumulative number of infected would reach approx. 260 000 people.

(For the higher resolution of figures presented below, open them in the new tab)
Strict preventive measures (pi - 0.4)

Infected                                                                                                                                                            Removed

   

 

Moderate prevention (pi - 0.6)

Infected                                                                                                                                                            Removed

 

Very loose adherence to preventic measures (pi - 0.8)

Infected                                                                                                                                                            Removed

The forecasting plots present the infected (at left) and removed (the sum of recovered and dead; at right) compartments of COVID-19 cases:

  • the black dots left to the blue vertical line – the observed proportions of the infected and removed compartments, respectively, on the last date of available observations;
  • the blue vertical line – To;
  • the green and purple vertical lines – the first and second turning points, respectively. The first turning point is the mean predicted time when the daily number of infected cases drops down below the previous ones; the second is the mean predicted time when the daily number of removed cases exceeds the number of infected cases, and the third, i.e. the end-point, is the time when the median of currently infected cases turns to zero;
  • the salmon color area – the 95% credible interval of the predicted proportions after To;
  • the cyan color area – the 95% credible intervals of the prevalence and/that of the probability of the removal prior to To;
  • the gray and red curves – the posterior mean and median curves.

 

Updates:

4 March – 27 May 2020

Dependently on the scenario, the second turning point, e.g. the maximum of new daily COVID-19 cases, is more or less postponed relative to the first forecast. Nevertheless, the cumulative number of infected cases will reach from over one million to even six million, if no protective measures would be followed.

 

Strict preventive measures (pi - 0.4)

Infected                                                                                                                                                            Removed

 

Moderate prevention (pi - 0.6)

Infected                                                                                                                                                            Removed

 

Very loose adherence to preventic measures (pi - 0.8)

Infected                                                                                                                                                            Removed

 

4 March – 1 June 2020

The scenario of maintaining strict measures and social distance shows that the peak of all infected cases still remains around one million beyond the end of this year. Surprisingly, the forecast slightly changes if the protection would be at moderate or loose level. In both cases, the second turning point would be delayed from November and October to 16 and 3 December, respectively, however in the case of loose restrictions the cumulative of daily infected dropped from six to five million cases.

 

Strict preventive measures (pi - 0.4)

Infected                                                                                                                                                            Removed

 

Moderate prevention (pi - 0.6)

Infected                                                                                                                                                            Removed

 

Very loose adherence to preventic measures (pi - 0.8)

Infected                                                                                                                                                            Removed

 

 

4 March – 14 June 2020

The primary forecast has been extended to 600 days. The scenario of maintaining strict measures and social distance revealed the second turning point falling at the end of March 2021 and the mean peak of total infected cases reaching over 2 million. Regarding the protection of moderate or loose levels, the scenario becomes slightly more optimistic than primarily. In both cases, the second turning point would be delayed beyond the end of this year, in the mid of February and the end of January, respectively, and the curves are slightly flattening, to 3.6 and 4.75 million of new infections at maximum, respectively. Concerning the current level of loosening the restrictions in Poland, it may be assumed that the model of pi=0.8 is the most appropriate.

 

Strict preventive measures (pi - 0.4)

Infected                                                                                                                                                            Removed

 

Moderate prevention (pi - 0.6)

Infected                                                                                                                                                            Removed

 

Very loose adherence to preventic measures (pi - 0.8)

Infected                                                                                                                                                            Removed

4 March – 23 June 2020

The recent model is slightly more optimistic as the numbers of infected cases are dropping. Sustaining the high-level restrictions would delay the second turning to the beginning of May 2021 with the mean peak of total infected cases reaching approx. 1 900 000. The moderate and loose level draws up the scenarios of the second turning points falling into the beginning of April and end of March 2021, respectively, and the curves are more flattened accounting for approx. 3 and 4 million new infections at maximum, respectively. Concerning the current level of loosening the restrictions in Poland, it may be assumed that the model of pi=0.8 is still the most appropriate.

 

Strict preventive measures (pi - 0.4)

Infected                                                                                                                                                            Removed

 

Moderate prevention (pi - 0.6)

Infected                                                                                                                                                            Removed

 

Very loose adherence to preventic measures (pi - 0.8)

Infected                                                                                                                                                            Removed