In Hong Kong, influenza sentinel surveillance systems have been recently established. Methods that compare current data to data from recent weeks may be appropriate to indicate the start of peak influenza activity. These methods can produce reliable and timely alerts at the start of the annual influenza peak season.
Cowling BJ, Ho LM, Riley S, Leung GM. (2013). Statistical algorithms for early detection of the annual influenza peak season in Hong Kong using sentinel surveillance data. Hong Kong medical journal = Xianggang yi xue za zhi, (19 Suppl 4)