Fig. 4

Sensitivity analysis of model (1) by varying the value of β = 0.0012, 0.012, 0.12 with all other parameters fixed: b = 0.0121, η = 0.8, ξ = 0.8, γ = 0.46, ζ = 0.0123, σ = 0.0012, φ = 0.01, ψ = 0.012, v = 0.6, p = 0.6, γ ₁ = 0.33, γ ₂ = 0.009, γ ₃ = 0.025, μ ₀ = 0.069, μ ₁ = 0.000532, μ ₂ = 0.000532, S(0) = 100, A(0) = 70, B(0) = 60, C(0) = 50, R(0) = 0, and V(0) = 30.