Messenger RNA (mRNA) vaccines have transformed vaccinology, achieving unprecedented success during the COVID-19 pandemic. This review synthesises evidence on their safety, efficacy, and potential applications beyond infectious diseases, while addressing common misconceptions. Over 13 billion doses administered globally to date demonstrates a robust safety profile, with rare serious adverse events. Effectiveness against severe COVID-19 has been demonstrated with real-world evidence, with significant reductions in hospitalisations and mortality. Future applications include vaccines for infectious diseases and personalised therapies, with promising clinical trials underway. Misconceptions, such as DNA alteration and infertility, are debunked using peer-reviewed data. This article underscores mRNA vaccines’ transformative potential and the critical role of physicians in combating misinformation to promote public health.