Abstract Vaccine hesitancy, defined as delay or refusal of vaccination despite the availability of vaccination services, has been included by WHO among the top 10 global health threats. Individual decision-making process can be strongly affected by communication. The use of metaphors is common in public health communication and increased during the COVID19 pandemic. Although some evidence has supported the persuasive potential of metaphorical language over scientific language, further research is needed. Our study aimed at comparing the effects of neutral scientific talk with war and protective metaphors on health communication. An online survey was conducted on a convenience sample of Italian teenagers randomly allocated to three study arms. Each participant was invited to watch a specific version of an informative video on infections and vaccines (group 1: neutral-scientific approach, group 2: metaphorical-war, and group 3: metaphorical-protective approach). After watching the video, each participant responded to an ad-hoc questionnaire. A total of 2681 subjects were randomly allocated to the three groups. No significant differences regarding age, sex and geographical area were detected between groups. Median age of the sample was 17 years (mean 16,8) and 56.8% were girls. The general attitude towards vaccination in group 2 and 3 was largely positive, with the majority agreeing (strongly or tend to agree) on the fact that vaccination is important (group 2: 89%; group 3: 92%), safe (group 2: 91%; group 3: 92,5%), effective (group 2: 85%; group 3: 88%), and does not generate anxiety (group 2: 80%; group 3: 83%). Higher level of distrust against vaccines was found in group 1, where 32% of participating adolescents are strongly or tend to be anxious about getting vaccinated. The results of our survey suggest that emotional involvement evoked through the use of metaphorical language may have, at least in the short run, some positive effect on vaccine confidence. Key messages • Use of metaphors can be successfully used in public health communication. • Messages evoking either war or protecting concepts are more efficacious than plain scientific language.