Figure 3.

Relationship between strength of interaction and prevalence ratio for non-uniform interactions between influenza and SARS-CoV-2. The scenarios tested correspond to ${\theta }_1^{(I)}={\theta }_2^{(I)}={\theta }^{(I)}$ and ${\theta }_1^{(T)}={\theta }_2^{(T)}={\theta }^{(T)}$; other parameters were fixed to model the coupled dynamics of influenza and SARS-CoV-2 (cf. table 1). For negative interactions (top panel), the x-axis represents 1 − θ^(I) and the y-axis 1 − θ^(T); for positive interactions (bottom panel) θ^(I) and θ^(T). Hence, in either panel the true strength of interaction increases from left to right and from bottom to top. (Online version in colour.)