FIG. 1:

Effects of intrinsic proportion of asymptomatic transmission on the realized proportion of asymptomatic transmission and basic reproduction number, given variation in the mean generation interval of asymptomatic cases. (A) Increasing the speed of asymptomatic transmission (shorter generation intervals) increases the realized proportion of asymptomatic transmission, q. (B) Increasing the speed of asymptomatic transmission (shorter generation intervals) decreases the basic reproduction number ${\mathcal{R}}_0$. When ${\stackrel{‒}{G}}_a$ is smaller (larger) than ${\stackrel{‒}{G}}_s$, estimates based on the observed generation distribution for symptomatic cases (${\mathcal{R}}_0=2.5$; dashed line) are expected to over- (under-) estimate the true ${\mathcal{R}}_0$. For both panels, the circle denotes z = 0.5 and ${\stackrel{‒}{G}}_a∕{\stackrel{‒}{G}}_s=0.55$ whereas the triangle denotes z = 0.5 and ${\stackrel{‒}{G}}_a∕{\stackrel{‒}{G}}_s=1.8$. Solid lines show contours for q and ${\mathcal{R}}_0$ values. The dashed line represents the naive estimate that assumes ${\stackrel{‒}{G}}_a={\stackrel{‒}{G}}_s$. Here, we assume 1/r = 7 days, ${\stackrel{‒}{G}}_s=8\text{days}$, and κ_s = κ_a = 0.5.