Objectives: To describe the role of the internet and cognitive biases in the controversy surrounding chronic Lyme disease. The attribution of chronic but aspecific symptoms to Lyme borreliosis is a source of worldwide controversy. Patients and methods: Some patients attribute their aspecific symptoms to Lyme borreliosis even though, in fact, they have a functional somatic syndrome. Results: These patients' diagnostic and therapeutic wandering contributes to the above attribution and to their suffering. The Internet has deregulated the information market. Cognitive confirmation bias contributes to confinement in belief. Negativity bias explains the tendency of the human brain to select the most alarming information available. The narrative force of alarmist videos or personal testimonies acts like a nocebo effect. The social exclusion generated by adherence to this belief is a factor of reinforcement and aggravation. Conclusions: Deconstructing chronic Lyme disease with empathy and conviction is in patients' best interests.