Good news, in France, the number of daily cases of people infected with the coronavirus is stagnating a little above 20,000, and the incidence rate is already declining among young adults and in some departments.
What about immunity?
More than one in two French people is fully vaccinated, and this rate is close to or already exceeds 60% in some departments of the eastern half of France.
By also taking into account the 10 to 20% of inhabitants who have already been infected (and for some also vaccinated) in these regions, we could reach around 70% of the population supposed to be partially protected against this virus.
Therefore and after a complete vaccination, many wonder about the possible risks of infection and contamination.
Deciphering the risks with our journalist Nicolas Berrod.
Vaccinated, can I catch the Covid?
Yes, but the risk is reduced compared to an unvaccinated person.
Several studies advance the effectiveness of messenger RNA vaccines (Pfizer and Moderna) against infection by the Delta variant of around 60 or 70% according to Singaporean data in the real population.
Vaccinated and infected, am I contagious?
Several data confirms that vaccinated people can still be infected with the Delta variant and transmit the virus, even if the risk is a priori reduced.
A CDC report posted on Friday sounded like a thunderclap. 494 residents or tourists who stayed on the Cape Cod peninsula (Massachusetts) tested positive, the vast majority of them because of the Delta variant. 74% were fully vaccinated (with Pfizer, Moderna or Janssen), slightly more than the vaccination coverage of the population in this area (69%). However, among the cases studied, those vaccinated and those not vaccinated had the same viral load, that is to say the same amount of the virus, in the mucous membranes of the nose and throat. This is where we look for the virus when a person is tested.
According to the US health agency, this suggests that the two groups could have the same risk of transmitting the virus. “The effect of the vaccine on transmission will depend on when you are exposed to an infected person. If it is in the first five or six days, the effect would then be insignificant ”, indicates Claude-Alexandre Gustave. Another element could ensure that a vaccinee has less risk of transmitting the virus: being less often symptomatic, he has less opportunity to cough and emit particles that may contain the virus.
But beware, viral load is not necessarily totally correlated with the risk of transmission.
If it is equivalent immediately after infection, it would drop much more quickly, after five days, in people who have been vaccinated, according to a preliminary Singaporean study posted online on Saturday.
Vaccinated and infected, can I develop a severe form?
Yes… But there is very little chance.
And this is the good news of the various studies mentioned: the effectiveness of vaccines against severe forms remains very important.
For Pfizer, protection would be 88% against the risk of hospitalizations and 91.4% against the most severe Covid, according to Israeli data published July 22, and 96% against hospitalizations, according to Public Health England .