Figures 6.27 and 6.28 illustrate the results of estimations 1 and 2. Figure 6.27
shows that even prediction 2 was too optimistic. New cases registered after corresponding period T c (shown by “stars”) deviate from the solid blue line very fast.
Unfortunately, new calculations (performed with the use of fresher data sets (one of
them is shown in Table 6.24, prediction 3)) yielded similar results. In particular, the
accuracy of prediction 3 (e = 73.1) was even worse than for predictions 1 and 2.
The obtained results and comparisons with the above forecasts for Ukraine
confirm the conclusion that the quarantine in Ukraine and its capital Kyiv was
relaxed too early (in comparison with the EU countries). The epidemic dynamics in
Kyiv is similar to ones in Ukraine, the UK, Moldova, USA, and the world. Second
and next epidemic waves in Kyiv started before the first one finished.
Great values of the error e call into question the obtained estimates of the
epidemic characteristics. The average times of spreading infection s ¼ 1=q in Kyiv
vary from 0.5 to 8.3 days (see Table 6.24). These figures correspond to ones
obtained for Ukraine and Moldova, but probably are much higher than in the EU
countries (0.77–1.47), USA (1.45), and the UK (3.03).
The analysis of the COVID-19 epidemic dynamics in Kyiv allows us to discuss
the question: Could the pandemic be avoided? Let us compare the situation in Kyiv
and in Hong Kong. These cities have similar population, but Hong Kong has
introduced the relevant measures on December 31, 2019, as soon as alarming
information from Wuhan appeared on a social media platform. The Hong Kong
authorities immediately closed “transport ties with Wuhan” and increased “vigilance and temperature screenings at every border checkpoint, including the city’s
international airport and high-speed railway station in West Kowloon”. The hospitals were told “to report further cases of “pneumonia of unknown origin” [91]. As
a result, the accumulated number of cases in Hong Kong was 1045 on May 9, 2020.
For example, the number of infected people in Kyiv was 1.7 times higher.
Quarantine has been announced all over Ukraine on March 12, 2020. It happened 9 days after the first COVID-19 case was confirmed in Chernivtsi region and
7 days before the first case in Kyiv. On May 11, the corresponding numbers of
cases were 2396 and 1930, respectively. Taking into account that the population of
Kyiv exceeds the population of Chernivtsi region more than three times, it can be
concluded that the timely introduction of quarantine can effectively slow down
spread of the infection.
6.13 The World
In this section, we consider the first wave of the COVID-19 pandemic and present
the results of two SIR simulations for global dynamics.
SIR simulations for the COVID-19 epidemic dynamics in the world were performed with the use of V j and t j data sets presented in Tables 6.3 and 6.22 and two
different time periods T c taken for calculations. The results are shown in Table 6.25
(time moments correspond to Table 6.22) and Figs. 6.6, 6.7 and 6.29; some of them
6.12 Kyiv
83
shows that even prediction 2 was too optimistic. New cases registered after corresponding period T c (shown by “stars”) deviate from the solid blue line very fast.
Unfortunately, new calculations (performed with the use of fresher data sets (one of
them is shown in Table 6.24, prediction 3)) yielded similar results. In particular, the
accuracy of prediction 3 (e = 73.1) was even worse than for predictions 1 and 2.
The obtained results and comparisons with the above forecasts for Ukraine
confirm the conclusion that the quarantine in Ukraine and its capital Kyiv was
relaxed too early (in comparison with the EU countries). The epidemic dynamics in
Kyiv is similar to ones in Ukraine, the UK, Moldova, USA, and the world. Second
and next epidemic waves in Kyiv started before the first one finished.
Great values of the error e call into question the obtained estimates of the
epidemic characteristics. The average times of spreading infection s ¼ 1=q in Kyiv
vary from 0.5 to 8.3 days (see Table 6.24). These figures correspond to ones
obtained for Ukraine and Moldova, but probably are much higher than in the EU
countries (0.77–1.47), USA (1.45), and the UK (3.03).
The analysis of the COVID-19 epidemic dynamics in Kyiv allows us to discuss
the question: Could the pandemic be avoided? Let us compare the situation in Kyiv
and in Hong Kong. These cities have similar population, but Hong Kong has
introduced the relevant measures on December 31, 2019, as soon as alarming
information from Wuhan appeared on a social media platform. The Hong Kong
authorities immediately closed “transport ties with Wuhan” and increased “vigilance and temperature screenings at every border checkpoint, including the city’s
international airport and high-speed railway station in West Kowloon”. The hospitals were told “to report further cases of “pneumonia of unknown origin” [91]. As
a result, the accumulated number of cases in Hong Kong was 1045 on May 9, 2020.
For example, the number of infected people in Kyiv was 1.7 times higher.
Quarantine has been announced all over Ukraine on March 12, 2020. It happened 9 days after the first COVID-19 case was confirmed in Chernivtsi region and
7 days before the first case in Kyiv. On May 11, the corresponding numbers of
cases were 2396 and 1930, respectively. Taking into account that the population of
Kyiv exceeds the population of Chernivtsi region more than three times, it can be
concluded that the timely introduction of quarantine can effectively slow down
spread of the infection.
6.13 The World
In this section, we consider the first wave of the COVID-19 pandemic and present
the results of two SIR simulations for global dynamics.
SIR simulations for the COVID-19 epidemic dynamics in the world were performed with the use of V j and t j data sets presented in Tables 6.3 and 6.22 and two
different time periods T c taken for calculations. The results are shown in Table 6.25
(time moments correspond to Table 6.22) and Figs. 6.6, 6.7 and 6.29; some of them
6.12 Kyiv
83