Are we entering a fifth era of biological warfare? One that does not depend on the existence of a manufactured biological weapon, but rather seeks to weaponise fake news and disinformation to undermine public health efforts? As we move beyond the first year of the Covid-19 pandemic, we talk to Rose Bernard, doctoral researcher in global health security, in the Conflict and Health Research Group in the Department of War Studies. She believes the deluge of fake news that accompanied the coronavirus, along with the rapid rise of the anti-vax movement in the last 10 years, and misinformation during the Ebola outbreaks, reveal how damaging disinformation can be to public health efforts. We discuss how this new type of biowarfare could incorporate the use of cyber capabilities to undermine sociopolitical systems by virtually escalating natural outbreaks. Such a campaign could have a catastrophic impact – potentially diverting the course of an epidemic by preventing people from accessing treatment, increasing civil conflict, and provoking attacks on health workers.