key: cord-0706692-rfni76sv
authors: Nesteruk, Igor
title: Comparison of the coronavirus pandemic dynamics in Europe, USA and South Korea
date: 2020-03-20
journal: nan
DOI: 10.1101/2020.03.18.20038133
sha: 3e23cd5d645543daa209f7b236f2eca9b7e38056
doc_id: 706692
cord_uid: rfni76sv

The pandemic cased by coronavirus COVID-19 is of great concern. A detailed scientific analysis of this phenomenon is still to come, but now it is urgently needed to evaluate the disease dynamics in order to organize the appropriate quarantine activities, to estimate the required number of places in hospitals, the level of individual protection, the rate of isolation of infected persons, etc. South Korea has achieved the stabilization of the number of cases at rather low level. The epidemic dynamics there can be compared with its development in other countries to make some preliminary, but very important conclusions. Here we provide a simple method of data comparison that can be useful for both governmental organizations and anyone.

Some previous efforts to compare the epidemic dynamics in Italy and mainland China has been done in [1, 2] . Here we will try to compare the epidemics in Italy, Spain, Germany, France, Switzerland, and USA with the situation in South Korea, where the number of cases is stabilizing at rather low level and the mortality rate is not high. We improved the very simple method proposed in [1] which now can by applied for every country. To illustrate its application, the epidemic dynamics in Austria was estimated.

Tables 1 and 2. Since the reports show the numbers accumulated by 10AM CET, we assumed that every number V j corresponds to the previous day. The values V j and corresponding moments of time t j and t ej are shown in Tables 1 and 2 Table 1 

The information from [3] . The corresponding time moments t j and the accumulated confirmed numbers of cases V j in South Korea. All rights reserved. No reuse allowed without permission. perpetuity. preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in 

We have to calculate the number of days from start of the epidemic outbreak (which is different for every country, see red values in the last column of Table 2 ) to compare with the data set listed in Table 1 . To increase the accuracy, we let this number to be non-integer. To calculate the corresponding time difference d t , we use the parabolic interpolation for the initial number of cases V in South Korea. The first three points in Table 1 yield the corresponding equation:

Then by putting into (1) the values V=V b for the number of cases at the starting day of the epidemic outbreak (shown in red in Table 2 ), the corresponding values d t were calculated for every country with the use of formula

which yields a solution to the quadratic equation (1) perpetuity.

preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in

The copyright holder for this this version posted March 20, 2020. . https://doi.org/10.1101/2020.03.18.20038133 doi: medRxiv preprint

The synchronized data sets are shown in the Fig. 1 by "stars" for countries in Europe and by "squares" for USA. The data for South Korea are shown by red line with "circles". Blue "stars" represent the sum of cases for 5 countries in Europe. It can be seen that Italy, Spain and France have no chance for rapid stabilization of the number of cases. But it is still possible in Germany, Switzerland and USA. Very high mortality rate in Italy and Spain makes the situation really dramatic. Blue "stars" in the Fig. 1 still follow the straight line. It means that the number of cases in Europe still increases exponentially and is far from stabilization.

It seems that main reason for the rapid increase in the number of cases in Italy and Spain is the slow isolation of infected and contact persons. For example, in South Korea an infected person spreads the infection approximately 4.3 hours (in average), [4] ; the mortality rate is 0.92%. By comparison, in mainland China this time is estimated as 2.5 days [5] .

For example, let us illustrate the application of this simple procedure for Austria. The number of cases in this country was V b =66 on March 6, 2020. Let us suppose that epidemic in this country started on this day. Corresponding value of t ej = 13 (see Table 2 ) and d t =0.3542 (according to eq.

(2)). If we want to know how looks the situation on March 15, 2020 (ninth day of the epidemic), we open the corresponding WHO report (number 56) and find their the number 959 for Austria. This figure has to be compared with the number of cases from Table 1 , corresponding to the time moment 9+0.3542. To avoid any additional calculations, let us take the value 2337 for comparison.

Thus the situation in Austria does not look bad. This country is able to stabilize the number of cases soon.

The situation with the coronavirus pandemic in Europe is very threatening. Italy and Spain are in urgent need of assistance in speeding up the isolation of infected and contact persons.

How can we estimate the dangers of the coronavirus epidemic in Europe?

Comparison of the coronavirus epidemic dynamics in Italy and mainland China

Coronavirus disease (COVID-2019) situation reports

Estimations of the coronavirus epidemic dynamics in South Korea with the use of SIR model

Characteristics of coronavirus epidemic in mainland China estimated with the use of official data available after February 12, 2020

I would like to express my sincere thanks to Ihor Kudybyn for his help in collecting and processing data.