Covid – Omicron: why do the first symptoms appear faster with the new variants?

Since the beginning of the pandemic, the incubation time decreases with each new variant. That’s why.

the covid continues on its way. Two and a half years after the start of the health crisis, the game is not over yet. All the health authorities around the world agree that a bounce looms in the fall. The fault of the return of winter and indoor gatherings but also of the start of the school year, a favorable context for the spread ofepidemic.

However, the sickness continues to evolve. Indeed, the new variants change things. Less severe, more transmissible, they modify the reading of the pandemic.

This Monday, August 22, a Chinese study has confirmed that the incubation period decreased with the appearance of new variants. 5 days on average with the strain Alphait increased to 3.42 days with Omicron.

“The results of this study suggest that SARS-CoV-2 evolved and mutated continuously throughout the COVID-19 pandemic, producing variants with increased transmission and virulence”write the authors of the study.


American epidemiologist Michael Mina has another theory.

“The symptoms start for two completely different reasons.

1- The virus directly causes damage to the body (breathing difficulties, loss of smell, etc.)

2- The immune system recognizes the virus and defends the body (fever, congestion…)”he develops on Twitter

Symptoms Can Start from

1) Virus Damaging the Body (Difficulty breathing, loss of smell, etc.)


2) Immune System Recognizing Virus & Defending Body (fever, congestion,…)

Whether Infection is a Breakthrough (ie: w Pre-Existing Immunity) defines Why/When Symptoms start


—Michael Mina (@michaelmina_lab) August 23, 2022

“But most Omicron contaminations are breakthroughs” immunity in people who have already been infected with another variant or who have been vaccinated. In the case of Omicron, it is the immune recognition process that actually leads to a faster reaction.

The previous variants caused damage to the organism. Hence later symptoms.

“It’s not very surprising after all. We are starting to be infected with seasonal coronaviruses like babies”concludes the scientist in a very interesting Twitter thread.

It’s Not Surprising that the Incubation period for

3.4 days (95% CI, 2.88-3.96 days)

Is Almost Identical to

3.2 days (95% CI 2.8–3.7)

Both are Breakthroughs… We start getting infected w Seasonal Coronas as babies!

—Michael Mina (@michaelmina_lab) August 23, 2022

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