Due to the COVID-19 outbreak, there is an urgent need to research the spread of disease and prevention
strategies. As the spread of COVID-19 is closely related to the structure of human social networks, there are a
lot of existing works that use a topological structure to analyze the characteristics of spread. Several studies
have ...
Due to the COVID-19 outbreak, there is an urgent need to research the spread of disease and prevention
strategies. As the spread of COVID-19 is closely related to the structure of human social networks, there are a
lot of existing works that use a topological structure to analyze the characteristics of spread. Several studies
have proposed certain strategies to prevent COVID-19 by analyzing the topological structure of the contact
network, but most of the existing works have focused on detecting dense groups such as cliques; however, as
the clique is the densest subgraph, it is easy for it to be influenced when the data has noise or lacks some edges.
To reduce the influences of noise or lacks of data, there is a concept of γ-Quasi-Cliques is considered in this
paper. γ-Quasi-Cliques is less restrictive and denser than cliques, and it is thus more suitable for analyzing and
detecting communities in social networks to identify the close contacts of patients and achieve timely control
under high levels of epidemic prevention strategies. Therefore, this paper proposed an algorithm based on the
traditional formal concept analysis method for detecting γ-quasi-cliques, and also designed a model for
detecting and mining close contacts and sub-close (secondary) contacts in the patient's contact network.
Consequently, manual intervention occurs in response to the asymptomatic close or sub-close contacts detected
by this model, and nucleic acid testing and home isolation are performed to prevent the widespread of COVID19. In our experiments, a real-life contact network is used to determine the ideal value of γ for the detection of
quasi-clique, which is 0.6, and the results show the validity and feasibility of the model.