Vaccination has been a central strategy in the global response to the coronavirus pandemic. In France, the vaccination campaign began in December 2020, and since then, several booster campaigns have been launched to maintain immunity, especially among the most vulnerable populations. The Ministry of Health explains that immunity from vaccines declines over time unless the body is exposed to the virus. This decline is more rapid for individuals with weakened immune systems, such as the elderly. A new booster campaign is set to run from October 14, 2025, to January 31, 2026, aiming to protect high-risk individuals as winter approaches and the virus becomes more active. The campaign targets people aged 80 and over, those with weakened immune systems, residents of elderly care facilities, and individuals with specific health conditions that increase their risk of severe illness. For these groups, the vaccine is fully covered by health insurance. Others may choose to get vaccinated, but it is not recommended for non-priority groups. The booster will use the Pfizer mRNA vaccine, adapted to the currently dominant JN1 variant, which is a subline of BA.2.86 and itself a subvariant of Omicron. A new variant, NB.1.8.1., is emerging in Asia and could become dominant in Europe by summer. For children under 11, vaccination is recommended for those at high risk of severe illness, including those living with immunocompromised individuals. Children aged 6 months to 4 years who have certain conditions, such as heart disease, diabetes, or Down syndrome, are also eligible. The vaccine for this age group is a pediatric version of the Pfizer vaccine. For children aged 5 to 11, a single dose is sufficient, while younger children may require multiple doses depending on their vaccination history. Parental consent is required for minors under 18. Pregnant women are encouraged to get vaccinated from the first trimester, as it may reduce the risk of complications for both mother and child. Studies suggest that mRNA vaccines have few risks for pregnant women, including no increased risk of miscarriage or preterm birth. The French Medicines Agency (ANSM) recommends that women experiencing menstrual irregularities after vaccination report them through a designated form. Overall, the vaccine is considered safe, with mild side effects like pain at the injection site or temporary fatigue being common. Vaccination is generally safe, but rare serious side effects, such as myocarditis or pericarditis, have been observed, particularly with mRNA vaccines. These conditions are more likely to occur after the second dose and are typically mild and short-lived. The benefits of vaccination are considered to outweigh the risks, especially when compared to the potential complications of a coronavirus infection. The production and monitoring of vaccines involve rigorous testing and quality control to ensure safety and effectiveness. Despite the rapid development of vaccines during the pandemic, the process remains highly regulated, with extensive oversight from health authorities.