The very slight decline in the Covid-19 epidemic in Western countries and the hope aroused by vaccines should not make us forget that the epidemic has described since February 20 a new wave in the world which, in number of cases daily diagnosed, is the strongest since the appearance of Covid-19.
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With 820,000 new contaminations identified on April 24 on the planet (and the dynamic is not weakening), the previous peak of January 11, 2021 (739,000 contaminations) has already been exceeded. And these are only the diagnosed cases: the reality is undoubtedly much higher. The fact remains that these values, even imprecise, above all make it possible to observe the dynamics of the epidemic.
In this case, these figures on a global scale are largely due to the epidemic wave which hit India, the second most populous country in the world (1.37 billion inhabitants, or nearly 20% of the world population), where a new variant, called "
Indian
" is
rife
. On April 24, nearly 350,000 people were diagnosed positive for Covid-19, or nearly 40% of the contaminations listed that day in the world [on the graph, the values are slightly lower because the data is smoothed over a week , Editor's note].
And the researchers make no secret of it: here again, the real number of contaminations is far above the official figures. In
L'Opinion
, Jean-Joseph Boillot, researcher at IRIS, even declared: "
the last figures, you have to multiply them by 30, to keep it simple
". The order of magnitude, to be taken with caution, would therefore be some 9 million daily contaminations ... However, the dynamics of the epidemic since the second half of February still follow an exponential dynamic. “
The principle is simple. Each day you multiply the value you observe by a constant number. It doesn't seem huge at first, but it quickly becomes so
, ”explained
Le Figaro
a few days ago.
biostatistician Catherine Hill, head of department at the Institut Gustave Roussy.
What about the United States or Brazil?
Since the start of the epidemic in March 2020, exponential curves have been observed on several occasions (including in France) but not with such a steep slope and lasting so long.
We can in particular compare the current "
Indian wave
»Which has been on an exponential trajectory for about 2 months already (and there is no indication that it is over) with the progression of the epidemic in the United States from the end of September to mid-November: it was again, an exponential trajectory that lasted a little over a month and a half, but the slope of the contaminations curve was much less steep than that observed today in India.
In addition, the screening policy in the United States, if not exhaustive, was more massive and therefore closer to reality than that of India.
In absolute value, this epidemic wave hitting India is therefore the strongest recorded in the world since the start of the epidemic.
However, it is also necessary to observe these data in proportion to the Indian population.
In this regard, the number of daily contaminations reported to one million inhabitants shows that India is still behind Brazil or ... France. Nevertheless, this graph must be taken with caution: on the one hand because, once again, screening policies are not the same in all countries; on the other hand, this lower ratio for India, which is explained by its very large population, may also mean that the epidemic still has a large margin of progress before it reaches an inflection point. Again, faced with an exponential, it is the dynamic that counts and not the value of the day ...
In terms of deaths, India has recorded an additional 2,767 deaths over 24 hours, a new sad record for the country which has recorded 192,000 deaths since the start of the epidemic, placing it fourth in the world .
But, again and at the risk of repeating ourselves, more than the absolute values, it is the dynamics of the curve that is the most worrying: the slope of the curve is again much steeper than that recorded in the United States of America. 'October 2020 to January 2021 or to that recorded in Brazil from January to April 2021.
And, of course, for the same reasons as for the contaminations, these thousands of deaths plunge India just to the level of the world average when they are brought back to the population, but this lower value is not more reassuring. however.
Faced with this "
storm
", in the words of Prime Minister Narendra Modi, local authorities have extended the confinement in force in the capital New Delhi by one week.
"
The ravages of the coronavirus continue and there is no respite,
" Delhi Chief Minister Arvind Kejriwal said.
The social network Twitter confirmed to have deleted, at the request of the Indian authorities, dozens of tweets which criticized the executive in the management of the health crisis.
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In hospitals, witnesses describe corridors cluttered with beds and stretchers and families begging in vain for oxygen or a place for their dying loved ones. “
I saw three corpses in six minutes,
” says Ravi Kumar, who managed to get his octogenarian grandfather admitted to a hospital in the capital after waiting all night. "
Inside there are no beds, just stretchers side by side with two patients on each
."
Faced with this dramatic situation, countries offered to help India.
Germany, the United Kingdom, France, the United States but also the European Union, via its European Civil Protection Mechanism, will deliver equipment in the coming days.
London and Paris, for example, have promised "
respirators
" while Washington, without directly promising vaccines, will send "
components
" for their production.
Two outstanding questions
At the same time, other countries, or the same ones, are more or less closing their doors to India. Neighboring Bangladesh will suspend land crossings for two weeks. The United States is advising against travel there, while Canada suspended flights from India and Pakistan for 30 days on Friday. France for its part set up a new protocol on Saturday to stop the arrival of variants. Travelers from five at-risk countries - Brazil, India, South Africa, Argentina and Chile - are tested for antigen upon arrival in France, in addition to a PCR test performed before the flight, and must be in solitary confinement for ten days.
The Indian variant is in any case already present on the Indian continent since the first cases of the latter were discovered in Belgium, Switzerland and Sunday in Greece.
Read also: Contagiousness, mortality, resistance to vaccines: are the different variants of Covid-19 really more dangerous?
The next few days and weeks will be decisive, with two questions that remain unanswered.
First
, how long will the epidemic continue on this same trajectory in India, knowing that the curve, because it is exponential, could quickly display values hitherto unobserved during this epidemic?
The "
Indian variant
" will implant he sustained in countries other than India?
