Epidemiology and Infection

Influenza

Factors associated with social contacts in four communities during the 2007–2008 influenza season

F. DeSTEFANOa1a2 c1, M. HABERa3, D. CURRIVANa4, T. FARRISa4, B. BURRUSa4, B. STONE-WIGGINSa4, A. McCALLAa4, H. GULEDa2, H. SHIHa3, P. EDELSONa1 and S. WETTERHALLa2

a1 Centers for Disease Control and Prevention, Atlanta, GA, USA

a2 RTI International, Atlanta, GA, USA

a3 Emory University, Atlanta, GA, USA

a4 RTI International, Research Triangle Park, NC, USA

SUMMARY

Mathematical models of influenza pandemics are sensitive to changes in contact rates between individuals. We conducted population-based telephone surveys in four North Carolina counties to determine the number of social interactions between individuals during the 2007–2008 influenza season. Influenza activity was monitored through sentinel medical practices. Among 3845 adults, the number of social contacts varied with age, was lower on weekends than on weekdays, and further decreased during school holiday periods. Adults with influenza-like illnesses had fewer social contacts. Adults' contacts in the community setting increased during periods of peak influenza activity. Among 290 children, potential contacts (i.e. other people in the same location) were lowest among preschool-age children and decreased on weekends and during school holidays. In adjusted analyses, children's potential social contacts did not change during periods of peak influenza activity. These results should be useful for modelling influenza epidemics and pandemics and in planning mitigation and response strategies.

(Accepted September 12 2010)

(Online publication October 14 2010)

Correspondence:

c1 Author for correspondence: F. DeStefano, M.D., M.P.H., Immunization Safety Office, MS D-26, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA. (Email: fdestefano@cdc.gov)

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