Charting the spatial dynamics of early SARS-CoV-2 transmission in Washington state
Fig 6
Comparison of simulated trajectories using the maximum likelihood parameter estimates with observed data.
A) Simulated trajectories for King county initialized on January 12 2020. Blue shading corresponds to the probability mass estimated from 50,000 sampled trajectories, with the sample mean shown in red. The orange curve is the observed hospitalizations data used for parameter inference, and lies in the tail of the probability distribution—suggesting an atypical trajectory. Also shown is the simulated trajectory most similar to the observed data (grey curve) as calculated via the sum of errors. B) Simulated trajectories for King county initialized on February 9 2020 using the state variables of the most similar sample (see panel A). Our results suggest that, once the initial atypical stochastic spread had occurred, the subsequent epidemic trajectory was largely a deterministic response to non-pharmaceutical interventions and susceptible depletion.