Table 1. Model comparison.

See Fig. 1 for a diagram of the general epidemiological model and the main text for a summary of the different models and their corresponding names used here.

Models	Epidemiology			Evolution		Number parameters	AIC
Models	H1N1	α ≠1 ρ_winter & ρ_summer	Seasonal forcing	Loss of immunity w_ε ≠ 0	Transmission w_β ≠ 0	Number parameters	AIC
Basic	×	×	Periodic splines	×	×	14	4493
Basic-H1	√	×	Periodic splines	×	×	17	4478
Refined	√	√	Periodic splines	×	×	19	4471
Humidity	√	√	Specific humidity	×	×	15	4484
Immunity loss/transmission	√	√	Periodic splines	√	√	22	4450
Transmission	√	√	Periodic splines	×	√	21	4458
Immunity loss (continuous)	√	√	Periodic splines	√	×	21	4448
Immunity loss (cluster)	√	√	Periodic splines	√	×	20	4445