The study presents a detailed analysis of the discursive exchanges that occur in social networks established on Twitter and Facebook from the Dengue Fever tag. The research presents three analyzes: multimodal, lexical and networks to understand and a general and lexical analysis focused on presenting the discursive exchanges between the characters, scenarios, spaces and times of composition of the environments and interfaces of networks occurred in relation to the tag and the meme DENGUE FEVER. The methodology was performed by virtual observation. A qualitative analysis with temporal clipping of thematic groups on Facebook and Twitter. The networks were configured as centralized and random, the knowledge exchanged focused on diagnoses, symptoms and ways of treating the disease, and multimodality contributed to an exchange of reification of knowledge of the groups observed.