Healthcare-acquired influenza is associated with patient morbidity and mortality. Annual vaccination of healthcare workers (HCW) is an important preventive measure to avoid the spread of influenza virus, but HCW vaccination is not mandatory in Switzerland for legal reasons.
Before 1994, HCWs’ influenza vaccination rate at HUG was very low (<10%). The use of various intervention strategies (multiple teaching sessions, institution-wide information campaigns, facilitated access to vaccines) increased HCW vaccination coverage from 14% in 1994 to 21-27% between 1996 and 2008.
Since 2009, an additional measure has been introduced and a badge with the message "I am vaccinated against influenza to protect you" is now given to all vaccinated HCWs. Non-vaccinated HCWs are required to wear a mask during the entire seasonal influenza epidemic period. Apart from 2009 (pandemic A/H1N1 2009), vaccination coverage peaked at 29%. In 2011, only 55.4% of HCWs respected the recommendations (vaccination or correct mask wearing in the proximity of the patients).