Discussion

Fact 1. Clearly , Covid-19 is not SIR (susceptible - infected - removed) but more likely SIRS (susceptible - infected - removed- susceptible) epidemic model.

Fact 2. The number of waves for most of the countries in the 2 years epidemic is 4 (with 3 and 6 waves, being the 2nd and 3rd frequent number of waves). This supports that the average reinfection period is about 6 month.

Fact 3. The chaotic dynamics of huge number of new daily cases of the mild variant OMICRON suggests to use EPI computations via different qualitative characteristics such as severity or mortality, e.g., daily hospital occupancy , daily ICU occupancy, daily death cases.

To describe the chaotic dynamics of huge number of new daily cases of the mild variant OMICRON, it is suggested to perform EPI & ERI computations via different qualitative characteristics such as severity and/or mortality. Different data sets, e.g., daily hospital occupancy, daily hospital admissions, daily ICU/MV (mechanical ventilation) beds occupancy, and daily death cases/mortality, are used to produce, so-called, EPI&ERI-style graphs. See graphs on Extras page.

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Epidemic Index @EpidemicIndex - Jun 3

UK #Covid19 vaccination campaign.

The new daily cases data clearly indicates waning immunity of vaccine protection.

EAI - Epidemic Acceleration Index

For more info and data go to EAI page.

Temporarily, from 1 May 2021, EPI data for the UK nations will not be calculated. Currently, all 4 nations have R number/EPI < 1. Meanwhile, please, continue to be Covid vigilant, and do your bit to defeat pandemic by staying healthy and keeping safe. Remember, Covid is NOT OVER yet.

The pandemic is surging in Austria, France, Germany and Italy (EPI > 1 and ERI > 1). Another wave? More info on page 2nd wave.

There are signs that the pandemic in the UK is slowing down. R number/EPI<1. The Risk ERI is decreasing. For more data and graphs, go to UK nations page.

Turkey: On 25 November 2020, it was announced by the Health Minister that for the first time since July numbers of daily new cases will include positive cases that do not show symptoms [source ], As a result of this decision, there is a big jump in daily new cases: 23 Nov - 6 713 cases; 24 Nov - 7 381 cases; 25 Nov - 28 351 cases; 26 Nov - 29 132 cases.

France: R number/EPI - up. Argentine: R number/EPI - down.

The EPI (R number) graphs of the UK and Ireland show that the carefully choosen strict LOCAL / regional tiered lockdown measures (in the UK) are similar to the national ones (in Ireland).

The negative trends continued, unfortunately, the whole August. And they keep going in September. Western Europe countries, who managed to decrease their first epidemic wave peaks by 10-20 times, now face the possible second wave. Their EPI (R-numbers) are above 1 for about 2 months. As a consequence, their ERI (risk numbers) are now also more than 1. See more data and graphs in Graphs, More Graphs , Home , ERI and EPI vs ERI .

Summer time and Covid-19 Pandemic.

Possible strategies:

(i) A "strict punishment" philosophy, that is to introduce a strict lockdown, when the number of daily cases attains a certain level. Clearly, it is the best if the vaccine will be delivered soon.

(ii) A "soft punishment" variant, that is to try to reduce the number of daily cases to the "managed level" by localised lockdowns and other localised measures, avoiding the state restrictions.

Whatever the strategy chosen by the government will be, falsifying statistics numbers for whichever "good" reasons, is the "best way" to get it wrong.

Example 1. (Based on Data for Aug 24, 2020).

EPI Egypt=0.93=EPI Bahrain. However, ERI Egypt=0.36<<1.63 =ERI Bahrain.

Egypt is in the green zone, Bahrain is not.

The travelling risk index in Bahrain (average number of cases per 100K) is also much higher than in Egypt.

Example 2. (Based on Data for Aug 24, 2020).

EPI Chile=1=EPI Indonesia. And the number of new cases is similar: 1877 (Indonesia)  and 1903 (Chile).

However, ERI Chile=1.34<<4.26=ERI Indonesia, i.e., the current Covid-19 dynamics in Indonesia is more dangerous than in Chile.

Moreover, the travelling risk index (average number of cases per 100K) in Indonesia is actually much smaller than in Chile.

ERI>1 and EPI >1, high risk, red alert: Belgium, France, Germany, Netherlands, Poland, Romania, Spain and UK.

ERI>1 and EP I< 1, moderate/moderately high risk, amber alert: Portugal.

ERI<1 and EPI > 1, moderately low risk, yellow alert: Ireland, Italy, Sweden and Switzerland. If the trend EPI > 1 continues, then the high risk danger increases.

ERI<1 and EPI < 1, low risk, green alert.

Below: data for 3 - 5 August 2020.

US: calculations of the EPI via new daily infected cases clealy indicate a second wave started at the middle of June. However, calculations via new daily death cases do not support it.

UK: unlike computations for US, the UK EPI graphs calculated via new daily infected cases and new daily deaths are similar.

The US EPI graphs: 12 March - 14 July 2020

The UK EPI graphs: 12 March - 14 July 2020

Several countries have low Epidemic Risk Index/ERI (low-risk nations): Belgium, Germany, France, Ireland, Italy, Netherlands, Spain, Switzerland. At the end of an epidemic wave, ERI is more relevant.

Country /EPI/ERI (Indices for the 27th June):

Belgium 1.05 0.34

Germany 0.76 0.70

France 0.99 0.66

Ireland 0.52 0.04

Italy 0.78 0.23

Netherlands 0.70 0.56

Spain 0.98 0.26

Switzerland 1.55 0.21

ERI - Epidemic Risk Index

Today a new index, ERI (Epidemic Risk Index), has been introduced and the ERI numbers for the selected countries have been published online. For more info about ERI, see ERI page on this website. Examples of ERI Graphs.

Country /EPI/ERI (Indices for 16th June)

World 1.07 3.39

US 1.08 3.96

UK 0.95 1.87

Turkey 1.32 2.65

Sweden 0.96 2.96

Singapore 0.98 1.78

Saudi Arabia 1.19 6.13

Russia 0.99 4.13

Pakistan 1.18 10.39

Peru 1.08 3.58

Netherlands 0.89 1.13

Mexico 1.10 6.79

Italy 0.99 0.31

Iran 1.05 2.00

India 1.09 7.85

France 0.96 0.62

Spain 1.20 0.28

Ecuador 1.13 0.98

Germany 0.97 0.42

Switzerland 1.31 0.13

Canada 0.69 1.10

Brazil 0.97 6.85

Belgium 0.74 0.36

The predictions for the total number of cases in the second wave provided it starts now:

Belgium-14K; Germany-63K; France-80K; Italy-52K;

Netherlands-37K; Spain-66K; Switzerland-3K; UK-340K;

US-5866K; Canada-70K; Brazil-3712K; Peru-538K;

Turkey-323K; Singapore-67K.

(The discussion was published on Twitter).

EPI - Epidemic Index

For 30 Apr, the new Epidemic indices (EPI) for the selected countries are as follows:

Belgium 0.57 (well done!)

Brazil 1.57 (struggling)

Canada 0.90 (yes, Canada went out of the dangerous zone of the exponential growth!)

France 0.64 (it seems before it was a mess up with the data)

Germany 0.72 (not bad when no change with EPI=0.72, then it will be over soon)

Iran 0.89 (going slowly but surely to the end of this epidemic cycle)

Italy 0.74 (ditto)

Netherlands 0.52 (close to the tens of newly cases!)

Russia 1.15 (improving!)

Sweden 0.95 (impressive - by doing it without the strict lockdown)

Switzerland 0.72 (the new cases numbers are about 100+,

the epidemic spread is under total control, to go further, probably,

it needs the contact tracing)

Turkey 0.68 (going strongly)

UK 0.96 (below 1 for 10th day in a row, but going very slowly)

US 0.95 (at last US went out of the dangerous zone).

(The discussion was published on Facebook page).