Influenza, as a contagious and common disease, is a continuing current problem and a threat to human health and life. According to the WHO, up to 1.5 billion people suffer from flu and even 1 million people die of influenza each year. Preventive vaccination is the most effective method for the prevention of influenza. According to the WHO recommendations, the largest possible proportion of the global population should be covered by the vaccination programme. In particular, people from high-risk groups and young children should receive vaccination. New vaccines against influenza appear at the turn of September and October, and it is the best time to get vaccinated. In Poland, however, the peak incidence of influenza falls between January and March, and therefore it is possible to be vaccinated at a later date. In the past two years, the incidence of flu in Poland nearly doubled, and the number of hospitalizations increased by almost half. The number of vaccinations in Poland has decreased almost three times over the last ten years. Timely data indicate that only 5% of the population get vaccinated against influenza. It should also be emphasized that in Poland the influenza-related costs, that is an underestimated problem, range between 40 and 700 million zloty per year.

Key words: influenza, the influenza epidemiology, complications of influenza, vaccination.