Background: The Belgian Superior Health Council recommends seasonal influenza vaccination for people working in the health care sector in order to reduce the risk of the influenza virus being transmitted to people at risk. The aim of this study is to provide more insight into the current vaccination rate in nurses and health care professionals in emergency services in Flanders. In addition, the influence of influenza vaccination on absenteeism will be investigated, as well as the motivation to get vaccinated or not. Methods: A quantitative multicentre, cross-sectional study was carried out in which nurses and health care professionals in emergency services in Flanders were questioned by means of an online questionnaire. Results: The survey of nurses and health care professionals in Flanders from 2018 shows that 54% (294/548) gets vaccinated in this year. Respondents who have been vaccinated report a lower absenteeism due to influenza compared to health workers who do not get vaccinated. There is a lack of general knowledge about influenza and vaccination. Thirty-four percent of nurses and health care professionals in emergencies do not know the correct definition of influenza. The main reasons for being vaccinated are: to protect oneself (27%), family members (21.5%) and patients (16%). Reasons for not getting vaccinated are: never having had the influenza before (30%), believing you get the influenza because of the vaccination (12%), no belief or trust in the vaccine (19%). Three percent of respondents who received the influenza vaccine were absent due to flu. The absence due to influenza was higher among the respondents who were not vaccinated, namely 11%. Being vaccinated for influenza or not has been associated with being absent for influenza. Conclusions: Given that there is a lack of general knowledge about influenza and its vaccination, the vaccination campaigns should cover this knowledge gap. Efforts to convince both nursing and care professionals about the protective role of the Influenza vaccine. ...