Effective Reproduction Numbers
We estimated the effective reproduction number (R effective) from the initial growth phase of the local hMPV epidemics using the generalized-growth method 25, which links the generation interval of the disease with the trajectory of the number of new cases per week to derive our R estimates. This method is especially useful to characterize a range of growth dynamics via 2 parameters: the growth rate (r ) and the epidemic growth scaling (p ). This growth dynamics value ranges from constant incidence (p = 0) to exponential growth (p = 1) 25. We assumed a gamma distributed serial interval of 5 and 7.5 days and a standard deviation of 1 day 26,27.