Dynamics of Single-City Influenza with Seasonal Forcing: From Regularity to Chaos

Figure 4

Dynamics with loss of individual immunity. Individuals now lose immunity (𝑘_rec=1; Figure 1). Parameters and initial conditions have the values in Table 1. (a) Short-term dynamics: susceptible 𝑛_sus and delayed 𝑛_del numbers are calculated with (2) and (1), the dynamic reproductive ratio 𝑅_dyn with (22), and hospital admission rate 𝐼_hos2 with (5). (b) Longer-term dynamics.

(a)

(b)