New wave of Covid-19: the XFG Variant is Restarting the Epidemic, Should you get Vaccinated?

As Covid-19 makes a comeback, some people are invited to be vaccinated again, from 14th October

Is Coronavirus Covid-19 making a comeback across France and Europe? For several weeks, indicators have shown an increase in contamination and reveal a rebound in the epidemic.

And this is accelerating. According to the latest network data Sentinels, the cases of Covid-19 are on the rise again. Between September 15 and 21, 2025, the incidence rate of Covid-19 cases among patients consulting for acute respiratory infection was estimated at 49 cases per 100,000 inhabitants, or 32,610 new cases, compared to 26,053 the previous week.

Behind these figures hides the XFG variant, also nicknamed “Stratus”, which is now the majority in Europe and is revealing itself particularly contagious. To the point of calling for a new vaccination campaign?

A more virulent variant?

Although this subvariant of Omicron XFG escapes herd immunity, the symptoms remain similar to those encountered during other epidemic waves.

“This most often remains infectious signs of the upper respiratory tree, fatigue, headaches, sometimes a loss of taste or smell”, explains Antoine Flahault, professor of public health at the University of Geneva, contacted by news.fr.

Despite measured virulence, certain categories of the population are more sensitive to it than others such as people over 85, infants, pregnant women, as well as immunocompromised patients.

Enough to ask the question of a possible vaccination, as the beginning of the vaccination campaign against Covid-19 and flu, scheduled for 14th October (excluding Mayotte).

Precautionary principle

So, should you get vaccinated? In any case, this is what Health Insurance recommends for part of the population, in one press release published on September 22, 2025.

“It is strongly recommended that people at risk of developing serious forms of Covid-19 be vaccinated, in order to be immunized against the SARS-CoV-2 virus”, we can read on the Ameli website. It lists all the people most at risk, including those over 65, and those suffering from comorbidities.

A precautionary principle what Antoine Flahault recognizes, even if the number of people who carry out these new injections remains limited. Vaccination coverage by these boosters is not very high in France and almost everywhere in the world, even in the elderly population at risk of complications. ”

During the last vaccination campaign, only 18% of the target audience had been vaccinated. Far from the success of the first campaigns, which allowed control of the epidemic.

How effective can we expect from it?

As the reminder International Journal of Medicine, only one vaccine is offered: the laboratory Comirnaty Pfizer, adapted to the Omicron sub-variant LP.8.1, which became the majority in Europe in spring 2025. Last July, it received marketing authorization. It is currently considered close enough to the strains in circulation to ensure good protection, especially against the most serious forms of Covid.

Even if questions arise about the duration of immunity, which diminishes over months. “The duration of the immune response with our messenger RNA vaccines is relatively short”, notes infectious disease specialist Odile Launay, in The Parisian. <

This protection is also questioned by Antoine Flahault. “It is time to conduct randomized trials again for these vaccine boosters in order to rigorously evaluate their effectiveness. ”

While some specialists ask progress of the vaccination campaign, the epidemiologist would find it more desirable to evaluate “the well-founded for their possible annual recommendation“.

Ventilate rooms well

Before any injection, a first weapon demonstrated its effectiveness: the port of protective mask, which limits Covid contamination, but also any other respiratory disease. You must also monitor the ventilation of the places you frequent.

“A good ventilation virtually eliminates any risk of contamination by these respiratory viruses or bacteria. Despite this, many schools remain very poorly ventilated, as do public transport, hospitals, nursing homes and prisons (where multidrug-resistant tuberculosis is spreading in particular), warns Antoine Flahault.

A situation that public authorities should take more seriously, according to the epidemiologist. To prevent Covid from becoming a regular visitor to our respiratory tract.