Related Experiment Video
Updated: Jun 24, 2026
High-throughput Detection Method for Influenza Virus
Published on: February 4, 2012
Estimation of the serial interval of influenza
Benjamin J Cowling1, Vicky J Fang, Steven Riley
1Department of Community Medicine and School of Public Health and bMicrobiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China. bcowling@hku.hk
Background:
: Estimates of the clinical-onset serial interval of human influenza infection (time between onset of symptoms in an index case and a secondary case) are used to inform public health policy and to construct mathematical models of influenza transmission. We estimate the serial interval of laboratory-confirmed influenza transmission in households.
Methods:
: Index cases were recruited after reporting to a primary healthcare center with symptoms. Members of their households were followed-up with repeated home visits.
Results:
: Assuming a Weibull model and accounting for selection bias inherent in our field study design, we used symptom-onset times from 14 pairs of infector/infectee to estimate a mean serial interval of 3.6 days (95% confidence interval = 2.9-4.3 days), with standard deviation 1.6 days.
Conclusion:
: The household serial interval of influenza may be longer than previously estimated. Studies of the complete serial interval, based on transmission in all community contexts, are a priority.
