𝛉A, 𝛉B | Percentage of infections with A or B which are asymptomatic | 𝛉A = 0.8 𝛉B = 0.4 | n/a |
ψA, ψB | Transmissibility of asymptomatic infections as a percentage of symptomatic infections transmissibility. (If ψ=0, then only symptomatic infections are transmitted, if ψ=0.5, the transmissibility of asymptomatic infections is 50% that of symptomatic, for ψ=1, transmissibility of both infections is the same. Potentially there could be an increase in the relative transmissibility of asymptomatic infections, due to lack of awareness of infections, and therefore no change in sexual behaviour (e.g. condom use or abstention). | 1 (No difference between asymptomatic and symptomatic infections) | n/a |
σAak, σBak | Recovery rate from asymptomatic infection with A or B per year (recovery rate = 1/duration) | σ = 2 per year, that is, average duration of 6 months without treatment, decreasing to 10 per year, i.e. 1.2 months duration with treatment | With treatment, recovery depends on efficacy of treatment and the average time taken to seek treatment. With treatment, recovery depends on efficacy of treatment and the average time taken to seek treatment. With treatment, recovery depends on efficacy of treatment and the average time taken to seek treatment |
σAsk, σBsk | Recovery rate from symptomatic infection with A or B per year (recovery rate = 1/duration) | | |