What would have happened in France in December 2021 and January 2022 without the vaccine?

Simple calculations, based on the number of cases among non-vaccinated people in December 2021 and January 2022, give a rough idea of what the vaccine has prevented.

Among unvaccinated adults aged 20 years and over, during December 2021 and January 2022, the epidemic caused 1,158 deaths, 1,899 critical care hospitalizations and 7,437 conventional hospitalizations per million people (See question What do the figures in France say about the effectiveness of the vaccine?). Applying these proportions to the entire population aged 20 years and over (51 million people), it can be estimated that if none of the people infected during this period had been vaccinated, the numbers of deaths and conventional hospitalizations would have increased fivefold, and the number of critical care hospitalizations would have increased sixfold. These are underestimates, because without the vaccine, the number of people infected would certainly have been much higher, as the vaccine also limits the transmission of the virus. And these figures may also be overestimated, because it is possible to think that, faced with a growing number of people suffering from COVID-19 In addition, these figures may be overestimated, as it is possible that, with more and more people becoming ill with HIV, people could have changed their lifestyles, reduced their social interactions or confined themselves, and thus limited the spread of the virus.

Moreover, with such a high level of burden on the hospital system (more than twice the number of daily critical care admissions than the peak of the first wave in March 2020), one can also fear serious additional collateral damage. In any case, this simple calculation at least gives an idea of what we have avoided through vaccination.

Conversely, if all people aged 20 years and over had been vaccinated before December (even without a booster), 3460 lives would have been saved (30% of total COVID-19 During those two months), and the numbers of admissions to critical care and conventional care would have been reduced by 43% and 28% respectively. This is a direct benefit for the people themselves and their families, and an indirect benefit for all those (patients and carers) who suffer from the overload of the hospital system.

For the sake of simplicity, a global analysis of the adult population (20 years and older) has been presented here, without taking into account theheterogeneity of risks. More detailed analyses, structured by age group, not explained here, confirm that in the absence of vaccination, the total numbers of conventional hospital admissions, critical care admissions and deaths would have been at least 4-6 times higher during these two months. Interestingly, these benefits were seen across all age groups. In particular, of the 81,600 critical care admissions that were prevented by the vaccine, 44% were for people under 60 years of age (and the same is true for conventional hospital admissions).