More and more people are using Internet to participate in electronic forum where they can exchange information about a particular disease, and patients and caregiver can find comfort and social support. This essay emphasizes the importance of these "virtual places" for health education and the promotion of disease self-management especially among patients with chronic or disabling pathologies. Secondly, it analyzes the factors enabling such solidarity creation and circulation among people who mostly do not interact with each other in the "real world". The sociality displayed in computer mediated communication among strangers is made possible by factors which can be related to technology means, service configuration and the social characteristics of participants. Finally, some currently active electronic forums devoted to chronic patients or disabled people are described as an example.