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Table 1 Main model parameters and their default values

From: An agent-based model simulation of influenza interactions at the host level: insight into the influenza-related burden of pneumococcal infections

Description Default value Rationale
Population size 100,000 persons chosen for computational purposes
Influenza virus
Transmission-probability rate Ν(mean 0.03; SD 0.001) per contact-day calibrated to match French influenza-like illnesses data [35]
Reporting probability of symptomatic cases 20%
Initial percentage of immune people each year 23%
Incubation period Γ(mean 2; var 0.1) [33, 34]
Symptomatic period Γ(mean 4; var 1) [26, 27, 34, 49]
Shedding period (1 day after asymptomatic state onset; 2 days after symptomatic state onset) [27, 33, 34]
Second pathogen (pneumococcus example default values)
Asymptomatic period duration Γ(mean 21; var 25) [18, 37]
Infection-probability rate 4.2e-5 per day calibrated to obtain an average annual incidence of 220 PI cases per 100,000 [38]
Symptomatic case-reporting probability 100% all PI cases are assumed to be reported
Symptomatic period duration Γ(mean 12; var 16) [38]
Shedding onset in the asymptomatic phase Day 0 [17, 39, 40]
Shedding end in the symptomatic phase Day 2 due to severity, PI cases are assumed to be isolated after 2 days of symptoms
Acquisition interaction (α12, α21) (1, 1) to be varied
Transmission interaction (θ12, θ21) (1, 1) to be varied
Endemic case: specific parameters
Carriage rate in the population (% of asymptomatic individuals) 20% [17, 39, 40]
Immunity-period duration (immunity reinitialized at the end of every year) 300 days no immunity assumed for pneumococcus
Pathogenicity interaction (π12) 1 to be varied
Epidemic case: specific parameters
Beginning of the 2nd pathogen epidemic U(30 – 60) days after influenza epidemic onset can be varied according to the chosen pathogen
No. of cases when the 2nd pathogen epidemic starts U(20 – 30)
Initial percentage of immune people 25%
Cross-immunity interaction (μ12, μ21) (1, 1) to be varied
  1. *SD: standard deviation.