Indicators of the coronavirus COVID-19 outbreak development
(A.B. Alyokhin, B.V. Burkynskyi, A.B. Brutman, A.I. Laiko, Z.N. Sokolovska)
Statistical monitor
13.05.2020. No 55.
We continue to publish COVID-19 outbreak’s IP progress indices in the world and in a number of countries, including Ukraine, according to official statistics as of May 12, 2020.
Most countries, except Iran (due to the continuing high level of new infections in recent weeks in this country), over the past day showed a positive trend of progress (Fig. 1–4).
In China, the level of progress indicator has risen slightly (99,86% vs. 99.83%). The value of the case fatality rates I(TC) and I(CC) hasn’t changed (5.59% and 5,60%, respectively). The forecasted completion date of the outbreak in this country also remained unchanged and is May 13–14, 2020, with unchanged forecasted final fatality rate of 5.59%. Let’s remind that at the final stage of the outbreak, its movement to the final state is asymptotic, therefore, the outbreak’s completion date forecast should be treated with due sense.
Generally, the outbreaks and pandemics’ ratings in the world, that we are monitoring, are shown in Fig. 5. The countries’ ranking over the past day has not changed.
Fig. 6 shows the dynamics of actual values of both case fatality rates generally accepted in medical statistics and progress indicator IP that we propose. Fig. 7–10 present the dynamics of the actual values of daily growth of the basic indicators of the COVID-19 outbreak in Ukraine and trends that best describe the relevant statistics. The graphs in these diagrams illustrate the development of the coronavirus outbreak in Ukraine until the present time.
Overall, the situation in Ukraine remains unchanged in recent days, and there is no reason to consider it as satisfactory, with the exception of a low level of fatality (Fig. 6). But let the victims’ relatives be the judge of that.
Ukraine has got stuck at the peak of new cases (Fig. 7), which transformed into a plateau, never being formed. Such a scenario isn’t favorable and characterized by an increase of the outbreak life cycle, the increasing burden on the health system (Fig. 10), additional victims of coronavirus (Fig. 9).
In our opinion, the main causes of this in insufficient compliance with quarantine by citizens of Ukraine and inadequate efforts by public authorities on the enforcement of quarantine measures. The liberalization of quarantine measures in the country, due to economic factors, will certainly contribute to such an outbreak.
In this issue we publish diagrams for coronavirus outbreak in Iran (Fig. 11–15), analogues to Fig. 6–10 on Ukraine, which is far ahead of many of the monitored countries as regards the level of progress. The aim of such diagrams is to provide a possibility to compare the COVID-19 outbreak in Ukraine and other countries of the world, to enable decision makers to draw conclusions.
Based on the analysis of Fig. 11–15, the following may be concluded:
Case fatality rates I(TC) and I(CC), on the example of the outbreak in Iran, show a classical behavior. In the early stages of the outbreak these figures behave chaotically, which eliminates the possibility (and feasibility) of their use as a tool of analysis. Then, they show a tendency to converge (one “top — down”, the other “bottom — up”) indicating the final value of the fatality rate. That’s the main point of simultaneous consideration (and demonstration) of the trajectories of these indicators’ values change.
The progress the IP, throughout the outbreak’s life cycle, indicates (pretty informative) the trend towards convergence of the above indicators of fatality, reaching 100% while achieving the same value by both fatality rates, which happens only at the time of final completion of the outbreak.
As can be seen from Fig. 12, Iran has passed quickly the peak of the cases, but allowed a new peak formation in the last weeks of observation period, once control of the situation lapses. The fatality rate in Iran is low (Fig. 11) compared to the “leaders” in this respect — some countries of Western Europe.
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Note.
A progress indicator (IP) of 1.00 indicates the end of the outbreak in the corresponding region, i.e. at the time without new infected, current patients are absent, all previously infected have added the lists of recovered and deceased.
Fig. 1 shows the values of the IP progress indicator for all countries of the world taken all together , China, countries of the world with the exception of China and several other countries.
Fig. 2 shows the “leaders” from among the analyzed regions and countries.
Fig. 3 shows the “average”.
Fig. 4 shows “outsiders.”
The terms “leaders”, “average” and “outsiders” are used solely to differentiate countries and regions by the level of the IP epidemic progress index and assign them to different diagrams for easy viewing and visual comparison.
At the time of the outbreak completion, the values of both WHO case fatality rates should be equal.
WHO case fatality rates unable to reflect sufficiently the outbreak dynamics. In contrast, the IP progress indicator accurately and informatively captures changes in the outbreak development.
The forecast for the outbreaks’ completion dates is calculated using a linear trend, determined by statistical data for the last decade of the observation period.
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Source of statistics:
https://www.worldometers.info/coronavirus/#countries
https://www.pravda.com.ua/cdn/covid-19/cpa/
Our publications:
https://www.facebook.com/MATHMODELCOVID19
https://t.me/mathmodelcovid19
Our initiative group and mission:
https://www.facebook.com/ab.alyokhin/posts/117804769862427
Our publications on case fatality rates and indicator of progress:
https://www.facebook.com/ab.alyokhin/posts/105684827741088