Changes Of School Children's Social Contact Network Between In Daily Life And During Influenza Epidemic

Objective: To describe changes of social contact networks among school children in the daily life and in the influenza epidemic period in a rural elementary school in Hubei Province. The purpose was to explore the influential factors for the potential transmission of influenza and put forward relative control measures at school.Methods: Convenience sampling survey was administered to the school children in the class where an influenza epidemic occurred recently. Characteristics of social contact networks in daily life and influenza epidemic period were compared by social network analysis and statistical analysis methods.Results: With intervention taken immediately by relevant departments, characteristic of social network structure had changed as follows. Compared with features in daily life, the network density decreased from 0.136 to 0.097, overall graph clustering coefficient decreased from 0.378 to 0.321, and geodesic distance index increased from 2.344 to 2.749 during influenza epidemic. The relative degree centrality decreased from 13.565 to 9.697, with significant differences (Z = -5.855, P < 0.001). The closeness centrality decreased from 43.065 to 36.816, with significant differences (Z = -7.043, P < 0.001). The number of k-plexs and n-cliques was much less than that in daily life period. During influenza epidemic, contact behavior characteristics changed as follows. The average amount of school children'primary links decreased from 6.682 to 4.492(Z = -4.574, P < 0.001), the contact hours per day decreased from 2.449 to 1.861(Z = -2.435, P = 0.015), and the contact level hours per person per day decreased from 5.665 to 4.375(Z = -2.264, P = 0.024), with significant differences.Conclusions: The characteristics of social contact network in school children increased the risk of influenza for the children who should be protected by our society. In our study, changes of school children'social contact network were in favor of the epidemic control. Although we still could not exclude other possibilities that changes might be due to instinctive responses by school children themselves, it also implied that quick intervention taken immediately by health department might be effective.