Characteristics of contacts in the form of time and the network structure (when and with whom) has an impact on the spread of infectious diseases. In connection with the development of computer methods, their methods have been applied in social networks analyze. On another level, the network structure of epidemiological models have been introduced. In this paper I present two types of infections: HIV and Chlamydia bacteria (ie, sexually transmitted infections: STI) and HA-MRSA (ie, hospital infection methicillin-resistant Staphylococcus aureus), which spread in different ways in different communities. In my study, I will focus mainly on secondary analysis of Swedish data of hospital infections and sexuality. Main, the general result of research is to restore the network of contacts in hospitals and to build sexual networks based on incomplete and highly sensitive data. The primary, a particular outcome for this study is to identify the most risky sexual behavior (for different groups of pathogens), their location in culture. I reconstructed, using an epidemiological model of q-MCMC (quasi-Monte Carlo Markov Chain), the outbreak of MRSA in a Stockholm hospital. I tried to locate and assess the potential role of ‘super-spreaders’ in a closed communities.