The epistemology of misinformation is a branch of epistemology with the objective of providing insight into the nature and spread of misinformation, fake news, conspiratorial theories, echo chambers, and epistemic pathologies in the formation of public opinion. This course focuses on medical misinformation, what harms it can cause, how it spreads, and strategies that have been advanced to minimize the harm of medical misinformation. Through a series of case studies, it also provides a critical perspective on the difference between misinformation and disinformation with an overview of how threat actors weaponize information during public health emergencies to cause harm. Topics covered may include concepts of scientific objectivity and universality; the communication of risk and risk perception; and the changing role of expertise in a fragmented public sphere; and the key role played by mainstream and social media in spreading both information and disinformation, propaganda, conspiracy theories, and fake news.