the end of 2022. Such a long-lasting pandemic is in line with the forecast for Africa
[104], according to which new COVID-19 cases will cease to appear only after
September 2021. Very surprising are the results for Sweden. Very long duration of
the epidemic wave (3–4 year) can be connected with the absence of lockdown in
this country. Maybe formula (13.6) developed for the cases with lockdown is not
applicable for Sweden. The final size of the recent pandemic wave can exceed
100 million cases in the world.
The forecasts given in Table 13.3 can usually be applied for a limited period of
time due to constant changes in the pandemic dynamics. For example, we have used
the period T c : October 1–14 for SIR simulations of the seventh epidemic wave in
Ukraine (see Table 10.1). Obtained value V 71 ¼ 398317 and the final day of this
wave: March 27, 2021, are in good agreement with the inequalities (13.5), (13.6)
and data for Ukraine given in Table 13.3.
In Chap. 10, we have detected new COVID-19 epidemic waves in Ukraine
caused by the local elections and the presidential poll, which took place across the
country on October 25, 2020. The apparent increase in contacts even before they
took place clearly accelerated the growth in the number of cases. Since the largest
value of the second derivative (Eq. (8.3)) corresponded to October 31 (see Fig. 10.1),
we chose this day as the beginning of the eighth wave and calculated the values V s
and daily number of new cases d s with the use of (13.1) and (13.2) and data set
presented in Table 8.2. The resulting figures V s = 395139 and d s = 8399.4 allow us
to calculate lower and upper limits for the final size V i1 and epidemic duration T s
(in days) after October 31, 2020, with the use of estimations (13.5) and (13.6):
667785 V 81 1102438
ð13:9Þ
133:6 T s 206:5
ð13:10Þ
Comparison of inequality (13.9) with the corresponding values in Table 13.3
shows that the elections and the presidential poll approximately doubled the
expected number of cases. The final number of accumulated cases in Ukraine can
be greater than one million. To compare the predictions for the final day of the
epidemic in Ukraine, it is necessary to subtract 37 days from the values given in
Table 13.3 (to take into account the difference in the values of t
Ã
s corresponding to
September 24 and October 31). After doing this procedure and comparing the
results with inequality (13.10), we see that estimates of the duration of the eighth
epidemic wave have not changed (they even became slightly smaller than for the
previous wave). Simple calculations using (13.10) show that the end of the eighth
epidemic wave can be expected from March 14 to May 26, 2021. All the calculations given in this book gave only underestimated values in relation to the number
of cases. We hope that effective quarantine measures and successful vaccination
will be able to reverse these trends.
160
13 Long-Time Predictions for the Pandemic Dynamics
[104], according to which new COVID-19 cases will cease to appear only after
September 2021. Very surprising are the results for Sweden. Very long duration of
the epidemic wave (3–4 year) can be connected with the absence of lockdown in
this country. Maybe formula (13.6) developed for the cases with lockdown is not
applicable for Sweden. The final size of the recent pandemic wave can exceed
100 million cases in the world.
The forecasts given in Table 13.3 can usually be applied for a limited period of
time due to constant changes in the pandemic dynamics. For example, we have used
the period T c : October 1–14 for SIR simulations of the seventh epidemic wave in
Ukraine (see Table 10.1). Obtained value V 71 ¼ 398317 and the final day of this
wave: March 27, 2021, are in good agreement with the inequalities (13.5), (13.6)
and data for Ukraine given in Table 13.3.
In Chap. 10, we have detected new COVID-19 epidemic waves in Ukraine
caused by the local elections and the presidential poll, which took place across the
country on October 25, 2020. The apparent increase in contacts even before they
took place clearly accelerated the growth in the number of cases. Since the largest
value of the second derivative (Eq. (8.3)) corresponded to October 31 (see Fig. 10.1),
we chose this day as the beginning of the eighth wave and calculated the values V s
and daily number of new cases d s with the use of (13.1) and (13.2) and data set
presented in Table 8.2. The resulting figures V s = 395139 and d s = 8399.4 allow us
to calculate lower and upper limits for the final size V i1 and epidemic duration T s
(in days) after October 31, 2020, with the use of estimations (13.5) and (13.6):
667785 V 81 1102438
ð13:9Þ
133:6 T s 206:5
ð13:10Þ
Comparison of inequality (13.9) with the corresponding values in Table 13.3
shows that the elections and the presidential poll approximately doubled the
expected number of cases. The final number of accumulated cases in Ukraine can
be greater than one million. To compare the predictions for the final day of the
epidemic in Ukraine, it is necessary to subtract 37 days from the values given in
Table 13.3 (to take into account the difference in the values of t
Ã
s corresponding to
September 24 and October 31). After doing this procedure and comparing the
results with inequality (13.10), we see that estimates of the duration of the eighth
epidemic wave have not changed (they even became slightly smaller than for the
previous wave). Simple calculations using (13.10) show that the end of the eighth
epidemic wave can be expected from March 14 to May 26, 2021. All the calculations given in this book gave only underestimated values in relation to the number
of cases. We hope that effective quarantine measures and successful vaccination
will be able to reverse these trends.
160
13 Long-Time Predictions for the Pandemic Dynamics