Seasonal influenza is a preventable infectious disease. In Switzerland, it causes several between 1000 and 5000 hospitalizations and about 400-1500 deaths annually both from the virus itself and from complications such as secondary bacterial infections (BAG 2017a). Vaccination is the most effective strategy to reduce virus transmission and decreases the severity of influenza, number of complications and deaths (WHO 2019). Public perception on influenza vaccines, associated risks and behaviours vary from year to year, between socioeconomic status groups, targeted risk groups, persons from different cultural backgrounds and from community to community. This makes it difficult for public health authorities and clinical providers to develop effective emergency preparedness, communications strategies to educate the public and to tailor their services. (CIDRAP 2016).
Numerous studies examine vaccination uptake and try to understand why people are often reluctant to get an influenza vaccination (Larson et al. 2014; Jarrett et al. 2014; Strelitz et al. 2015). This study is unique as it is the largest household survey on influenza in Switzerland and it focuses not only on individual characteristics from the survey but also on geographic area variables. This thesis aims at gaining insights concerning:
- Determinants of health related habits
- Health related habits and influenza-like illnesses
- Determinants of vaccination rates
- Determinants of vaccination hesitancy
- Identification of quarter effects – explaining urban quarter variability
The Federal Office for Public Health sees seasonal influenza as a serious disease, which leads to 112’000-275’000 annual doctor’s consultations, thousands of hospitalisations due to illness-induced complications and several hundred deaths in Switzerland alone (BAG 2017b). This project has a high and direct relevance for persons of the city of Basel, because (1) influenza infection is a very common problem within the population and (2) an infection is associated with high morbidity, mortality and health care costs (Chen et al. 2015). Therefore, it is vital to lower the infection rates with influenza. Putting disease incidences into a spatial context contributes to the understanding of transmission paths of influenza within urban populations and is therefore of greater relevance.