Poor knowledge of vaccination recommendations and negative attitudes towards vaccinations are independently associated with poor vaccination uptake among adults - Findings of a population-based panel study in Lower Saxony, Germany.

Objectives: The aims of this study were to (a) assess knowledge of official vaccination recommendations and attitudes towards vaccinations among adults and (b) examine their association with vaccination uptake among adults.

Methods: This study was part of the HaBIDS study (Hygiene and Behaviour Infectious Diseases Survey), which is an online panel established in March 2014 in Lower Saxony, Germany with males and females aged between 15 and 69 years (n = 2379). Every few months, participants completed questionnaires on different aspects of infectious diseases. In September 2014, knowledge of vaccination recommendations, attitudes towards vaccinations and information on uptake of vaccinations in the last 10 years (practice) were collected using a knowledge-attitude-practice (KAP) questionnaire. Multiple correspondence analysis was applied to identify underlying structures in each KAP domain and fractional polynomial regression analysis to examine the associations of knowledge and attitudes with vaccination uptake.

Results: Of the 2379 panel members, 1698 (71%) completed the KAP questionnaire on vaccinations. The majority of participants (80%) knew that the vaccine against diphtheria and tetanus should be administered every 10 years. Regarding other recommendations, the proportion of correct answers varied between 35% and 60%. 82% of participants agreed that adult vaccinations should be mandatory for selected groups such as health care workers and 40% stated that vaccinations should be mandatory for all adults. For the different vaccines, the odds of being unvaccinated were 1.5- to 5-times higher among participants with poor knowledge of vaccination recommendations compared to participants with good knowledge. Participants with negative attitudes towards vaccinations were also more likely to be unvaccinated.

Conclusions: Efforts should be undertaken to improve knowledge of official vaccination recommendations in the general population and reduce common misconceptions about vaccinations. This information can be provided during general practitioner visits or through media campaigns.