The Impact of Coinfections and Their Simultaneous Transmission on Antigenic Diversity and Epidemic Cycling of Infectious Diseases

Figure 12

Impact of simultaneous transmissibility on the interepidemic period and amplitude of infectious transmission dynamics. Two situations of transmissibility of single pathogen infection are considered: panels (a) and (b) 𝑅^𝑎₀=𝑅^𝑏₀=3.0 and immunity period = 3 years, (c) and (d) 𝑅^𝑎₀=𝑅^𝑏₀=17 and immunity period = 50 years. In panels (b) and (d), solid lines stand for the maxima while dotted ones lined the minima of the fraction of total infections. Other parameters are the efficiency of single transmission from coinfection (𝜙)=2 and the infectious period (1/𝛾_𝑎=1/𝛾_𝑏=1/𝛾_𝑑) in (a)-(b) which mimics influenza is 2 days while in (c)-(d) which mimics pertussis is 30 days. The first 100 years were discarded.

(a) 𝑅^𝑎₀=𝑅^𝑏₀=3, immunity period = 3 years

(b) 𝑅^𝑎₀=𝑅^𝑏₀=3, immunity period = 3 years

(c) 𝑅^𝑎₀=𝑅^𝑏₀=17, immunity period = 50 years

(d) 𝑅^𝑎₀=𝑅^𝑏₀=17, immunity period = 50 years