Mass immunization without public consent

The development of needle-free, nonintrusive vaccine technologies promises to transform public health campaigns by improving acceptability and ease of administration. However, this convenience introduces a critical ethical vulnerability: the potential for large-scale deployment without individual knowledge or consent, leading to nonconsensual immunization. This article analyzes this risk through the lens of established bioethical principles-autonomy, nonmaleficence, beneficence, and justice-and historical precedents, examining how the ease of use of nonintrusive formats, combined with precedents of rapidly enforced mandates, could undermine informed consent. To address this challenge, we propose a proactive governance framework based on three pillars: strengthening international ethical guidelines, enacting national laws against covert mass medication, and exploring technological monitoring of public infrastructure. This approach aims not to impede public health action, but to reinforce it by upholding individual autonomy and maintaining essential public trust.