Influenza Vaccination in high risk groups: guidelines revision and rationale for an Evidence Based Preventive strategy


Health care workers
High-risk groups


Influenza is a respiratory infectious disease that represent one of the main causes of excess winter deaths (EWDs)in Europe. Annual flu epidemics are associated with high morbidity and mortality rates, especially among the elderly, those with underlying health conditions and pregnant women.

Also Health Care Workers (HCWs)are considered an high risk group either for contracting influenza or for preventing transmission of influenza virus to vulnerable patients. Thus, these four target groups are mainly eligible for developing vaccination strategies.

During 2014/2015 season, the excess winter mortality rates observed in northern hemisphere countries (EuroMOMO network) and in Italy (+13%), was strongly related with the intensity of influenza circulation.

Influenza vaccination represents the most important public health intervention to prevent seasonal influenza transmission and infection.

However, to date, influenza vaccination coverages reported in Europe also among high risk groups are still largely unsatisfactory.

This study analyzes the International and European guidelines on influenza vaccination and the rationale which underlies the evidence-based public health intervention for prevention of influenza among the principal high-risk groups: a) the elderly (subjects with 65 years old or older); b) Subjects with underlying health condition; c) pregnant women; d) healthcare workers.

Only the achievement of recommended influenza vaccination coverage in all European Countries among high-risk groups could reduce the burden of disease and minimize the peaks of winter mortality related with influenza virus circulation.


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