Genetically modifying humans to be able to spread specific diseases is a very complex and highly ethically controversial issue. Current gene editing technologies, such as CRISPR-Cas9, are mainly used to repair or change specific genes to treat genetic diseases or enhance certain biological characteristics. However, these technologies have strict limitations and challenges in terms of technical capabilities, ethics, and law. From a technical perspective, genetic modification involves precise modifications to the human genome, which may affect the immune system or change certain physiological functions. But to deliberately design genetic modifications to make humans spread specific diseases requires a deep understanding of the complex interactions between viruses or bacteria and the human body, which is very difficult at the current level of science and technology. In addition, from an ethical and legal perspective, such behavior will cause huge controversy. Deliberately creating or spreading diseases is considered a type of biological weapon, and the international community has strict prohibitions and strong condemnations on the use of biological weapons. Overall, genetic modification to give humans the ability to spread diseases is not feasible and desirable, both from a technical feasibility and from an ethical standpoint.