Flu has repeatedly decimated the human population since ancient times. It was and still is still the cause of many human tragedies, many times at man’s own request, because we have a dismissive attitude to vaccination against influenza. Flu infects humans, regardless of age, latitude and time of year. For many years it is known that complications from influenza should be considered not only in terms of increased already existing chronic disease and / or unleash a new but also in terms of quantifiable financial costs. In Poland, according to the influenza season records there are from a few hundred thousand to several million cases and suspected cases of influenza and influenza-like illness. Samples taken from the respiratory tract can be tested in different directions using molecular biological methods. Correct diagnosis in the case of influenza infection is very important for proper treatment. In Poland, the anti-influenza drugs available are a new generation of neuraminidase inhibitors. They do not replace flu vaccination but are not necessary in the treatment of influenza. Prophylaxis against influenza by vaccination is the only most effective, least expensive way to prevent this dangerous infectious disease that the flu is. In Poland, split or subunit inactivated influenza vaccines are available, which are equally acceptable immunologically. The percentage of the population vaccinated against influenza in the country is outrageously low especially in children 6 month through 14 years – 0.96%. In the influenza season 2015–2016 only 3.4% of the population was immunized.

Key words: flu, infection, influenza vaccine.