Vaccination is the most effective way to prevent infection and severe outcomes caused by influenza viruses.
When the vaccine viruses closely match the circulating influenza viruses, efficacy rates in individuals younger than 65 years of age typically range from 70% to 90%.
Vaccination is especially important for people at higher risk of serious influenza complications, and for people who live with or care for high risk individuals.
WHO recommends annual vaccination for (in order of priority):
- nursing-home residents (the elderly or disabled);
- people with chronic medical conditions;
- elderly individuals; and
- other groups such as pregnant women, health care workers, those with essential functions in society, as well as children from ages six months to two years.