Analysis
of Seven Countries with Multiple Waves of Daily Confirmed Cases
Dr
Himanshu Shekhar
Russia,
Australia, Israel, Italy, Japan, Ireland, UK are discussed.
This
article contains analysis of different countries of the world where multiple
waves are observed, so as to motivate India to counter second wave efficiently and effectively.
Introduction
When India is passing through
second wave of COVID attack, I am flooded with questions, related to spread,
prediction, nature and performance of confirmed cases. I have got many messages
asking very interesting questions. Some of the questions put forth were as
follows:
Ø When will turnaround come for the second wave? 29 May 2021
Ø Is there a possibility of third wave? Yes
Ø What is role of vaccination on prediction? Nil
Ø Whether second wave is always more severe than first wave? No
Ø Whether complete control of Corona Virus is possible? No
I have answered most of the
questions to the best of my knowledge and capacity without making any comment
on system, management and state of affair. I am concentrating more on the
mathematical treatment of data, readily available in connection with daily
confirmed cases. In addition to daily number of confirmed cases, doubling
period and daily growth rate is also generated for India and Maharashtra, in
previous 3 posts. In this post, I am trying to look at the trends in different
countries of the world, in order to comment conclusively on the nature of
second wave, in India. The countries considered are Russia, Australia, Israel, Italy, Japan, Ireland and UK.
Total Confirmed Cases
Russia has two clear peaks in
daily confirmed cases. First peak occurred in May 2020 and has around 11500
daily confirmed cases. Second peak occurred in December 2020 and has a peak
slightly above 29000. After that the value of daily confirmed cases is continuously
reducing. The current level of daily confirmed cases in Russia stands at around
8000, which is still near the peak of first wave in Russia. The second wave is
found to be more sever here.
Australia and Israel has seen
two waves. The second wave is slightly more severe than the first wave.
Contrary to this Italy gave a situation where second wave is less severe than
first wave. Although complete control is not envisaged at present in Italy, but
reduction in daily confirmed cases is observed.
Japan has another peculiar
situation as far as daily confirmed cases are concerned. It has sustained three
waves of Pandemic and is currently witnessing fourth wave. Each wave in case of
Japan was more severe than previous waves. The peak of each wave was higher
than previous, but the duration of each wave in days was almost constant.
Ireland witness two smaller
wave in terms of peak values of daily confirmed cases. The peaks occurred in March
2020 and October 2020. However, it witnessed a third major peak in January 2021,
which was much higher. The daily cases were around 1000 for the first two
peaks, which reached 8000 per day for the third peak. However, now the daily
confirmed cases are controlled to less than 500.
UK has seen three waves almost
matching to Ireland. The first wave was in March 2020. The Second wave was in
November 2020. This second wave was slightly broader and peak persisted for
quite long duration. In fact third wave merged with this second wave and has a
peak in January 2021. The peak in UK was around 68000 per day. However, now the
daily confirmed cases have dropped to less than 3000.
Doubling period indicates
duration in days in which total confirmed cases in a country becomes double.
Higher value of doubling rate is desirable, as it indicates slower rate of rise
of confirmed cases. For Russia, two peaks were observed and doubling period
have these peaks indicated by troughs. The first trough was not clearly visible
due to larger scale of vertical axis. However, corresponding to second peak in
Russia, the trough of 62 days was observed in December 2020. After that
doubling period is continuously rising and current value is 147 days. The value
rationalized to one lakh total confirmed cases indicate current value of
doubling period for Russia as 6.2 days.
The doubling period for
Australia exceeds 250 days, indicating a very good control. Israel has doubling
period of the order of 120 days. Doubling period per lakh for Australia is
above 1500 days while for Israel, it is 28.6 days. The nature of both the
countries are quite different, but both displayed a very good control. Italy
showed a doubling period of around 180 days in first spell and the value of
doubling period have not attained this value, although it is continuously
rising. Doubling period per lakh have touched 109 days, during first phase but
the second phase values are just exceeding 6 days. Both these values are less
than that for Australia or Israel and control in Italy may not be absolute for
the time being.
Japan has witnessed three
waves of pandemic and the same is depicted by 3 troughs in the doubling period
curve. First nadir of the curve was 7 days, witnessed during April 2020, second
of 23 cays in August 2020, third in January 20201 of 41 days. It indicates that
doubling period was higher for each peak in Japan and better control is an
indirectly indicated. Current value of doubling period is exceeding 100 days. However,
doubling period rationalized to one lakh has opposite situation. The troughs
are seen at 189 days, 89 days and 22 days, corresponding to 3 peaks observed.
Doubling period for Ireland
has two distinct troughs. One corresponds to second peak and has a value of 49
days in November 2020. Second depicts the bigger peak of daily confirmed cases
and has a value of 21 days in January 2021. However, after that the value is
continuously rising and current value is around 110 days. For doubling period
rationalized to one lakh total confirmed cases, the value is currently around
100 days.
Doubling period corresponding
to each peak in UK was continuously rising and currently it is around 126 days.
The doubling period rationalized to 1 lakh confirmed cases is found to be
around 5.6 days for UK.
Daily Growth rate
Daily growth rate indicates
rate at which total confirmed cases are rising and it is calculated by using
compound interest formula under two assumptions – one is constant duration of 7-days
growth rate rational per day, and another is variable duration doubling rate
based growth rate rationalized to 1 day. For Russia both the peaks are capture
dwell by the growth rate curves, as depicted by their peaks. The current value
is 0.181% for weekly basis growth rate and 0.473% for doubling period based
growth rate.
Growth rate calculated by both the methods for Italy, have a current value of around 0.5%. However a peak of slightly above 4% is observed during October 2020 end and November-2020 first week. Daily Growth rate calculated on weekly bases for Japan has a value of slightly below 1% and it is rising, at present.
The growth rate based on weekly basis for Ireland has
very small value of 0.175%. Based on doubling period the growth rate slightly
above 0.6%. The nature of growth rate for UK was almost similar to that for Ireland.
The weekly basis value is currently at 0.05% and on doubling rate basis, it is
around 0.5%.
It is possible to get total
control in current scenario, even after second wave and it is really
participation of people, which is required to attain control on daily confirmed
cases. Many countries of the world have displayed this. Although countries
attribute this to lockdown, but smaller population, climatic condition,
food-habit, law-abiding citizen, proper display of social responsibility and of
course vaccination may be considered possible factors for such control. I am
leaving this judgement to readers to get correct picture and understand that
control is possible with collective commitment and participation of public. All
the best. Regards.
Dr Himanshu Shekhar
No comments:
Post a Comment