- Globally, Influenza occurs in adults with an annual incidence rate estimated at 5%–10%. Infection can result in hospitalization and death mainly among high-risk groups (the very young, elderly or chronically-ill patients)
- High-risk conditions include people with asthma, heart disease, chronic obstructive pulmonary disease, diabetes, or cancers other than skin cancer. Furthermore, toddlers, infants and children, pregnant women, elderly patients, healthcare professionals and occupancy workers belong to the high-risk population segment.
- Worldwide, annual epidemics are estimated to result in about 3 to 5 million cases of severe illness, responsible for 250 000 to 500 000 deaths
- Median vaccination coverage remains in the range of approx. 40% both in the US and major EU countries in adults except for UK and NL. Vaccine coverage did not increase over recent years and the target-coverage of 75% for 2020 is out of reach both in the USA and most European countries
- Vaccine coverage in high-risk/chronic conditions with vaccination recommendation like cardiovascular and respiratory diseases, as well as diabetes remains below 50% in adult patients aged 18 to 64 years
- Vaccine effectiveness for recent strains like H3N2 has been very poor during last years, ranging from 15% to 42% in Western countries. Furthermore, vaccine efficacy decreases significantly with patient age. In the flu season 2016/17 particular low figures have been reported for elderly above 60 years