Diffusion of information and viral content, social contagion and influence are still topics of broad evaluation. We have studied the information epidemic in a social networking platform in order compare different campaign setups. The goal of this work is to present the new knowledge obtained from studying two artificial (experimental) and one natural (where people act emotionally) viral spread that took place in a closed virtual world. We propose an approach to modeling the behavior of online community exposed on external impulses as an epidemic process. The presented results base on online multilayer system observation, and show characteristic difference between setups, moreover, some important aspects of branching processes are presented. We run experiments, where we introduced viral to system and agents were able to propagate it. There were two modes of experiment: with or without award. Dynamic of spreading both of virals were described by epidemiological model and diffusion. Results of experiments were compared with real propagation process - spontaneous organization against ACTA. During general-national protest against new antypiracy multinational agreement - ACTA, criticized for its adverse effect on e.g. freedom of expression and privacy of communication, members of chosen community could send a viral such as Stop-ACTA transparent. In this scenario, we are able to capture behavior of society, when real emotions play a role, and compare results with artificiality conditioned experiments. Moreover, we could measure effect of emotions in viral propagation. As theory explaining the role of emotions in spreading behaviour as an factor of message targeting and individuals spread emotional-oriented content in a more carefully and more influential way, the experiments show that probabilities of secondary infections are four times bigger if emotions play a role.