Influenza infections are associated with higher morbidity and mortality in chronically ill and elderly patients. To avoid nosocomial infections, preventive strategies have focused strongly on vaccination coverage in health care providers. However implementation in hospital settings is often not successful with differences at the level of profession and discipline. Although other preventive strategies such as hand hygiene, facial-masks and isolation have been discussed, there is paucity on process and outcome research.

The Healthcare –associated Influenza Prevention study (HaIP) is a program of studies focusing on the reduction of influenza in acute hospital settings. More specifically the HaIP program aims to:
·  Develop and test a complex intervention to improve prevention behavior and outcomes in hospital settings
·  Develop standardized methods to assess nosocomial influenza infections and adherence to preventive behaviors in health care workers

Methodologically the study program is informed by the Medical Research Framework (MRC) for development and evaluation of complex intervention. Quantitative and qualitative research methods will be used and combined according to the broad logic of the inquiry. Broadly this includes 3 work packages (WS1 intervention development, WS2 development and implementation of surveillance, WS3 implementation and testing of the intervention program)

WS1: For intervention development, qualitative interviews and focus-groups will be conducted with target groups. Based on this data a questionnaire will be developed and pilot-tested assessing changes in influenza prevention- behavior, attitudes and culture. Based on the generated evidence an intervention program will be developed and pilot tested using a participatory approach involving different stakeholders.

WS2: For the implementation of the surveillance system, measurement and documentation of nosocomial influenza, vaccination rates, adherence to hand hygiene and masks, isolation and other factors will be standardized and tested. Implementation of surveillance includes teaching of key players and is conducted in a step-wise approach across hospitals.

WS3: For implementation and testing of the intervention program an adapted step-wedge design will be used including hospitals with an implemented surveillance system. Formative evaluation will supplement these data. 

Nosocomial influenza is a serious health problem for chronically ill and immunocompromised patient groups. This study will improve understanding of the problem by generating systematic and comparable surveillance data. Additionally the intervention program used in this study will be based on comprehensive contextual knowledge and extend the so far heavily vaccination and education focused approaches. The program provides extensive data to understand the response to intervention and it’s mechanism in a complex setting. With that it has the potential to improve outcomes of nosocomial influenza.