Early estimates of COVID-19 infections in small, medium and large population clusters

Dawd S Siraj; Amir S Siraj; Abigail Mapes

is the (which was not peer-reviewed) The copyright holder for this preprint . https://doi.org/10.1101/2020.04.07.20053421 doi: medRxiv preprint infection is determined by the length of the infectious period (1/γ) and the basic reproduction number R 0 -the mean number of secondary infections from a single infected individual introduced into a fully susceptible population, a fixed value in this study. Once exposed, infected individuals stay in that state for the duration of the incubation period (1/ξ) and subsequently progress to the infectious state I, where they stay for the length of the infectious period (1/γ) until they are removed either through isolation or recovery. In our model, contact tracing coverage of θ is assumed to affect those that are in the infectious state where those affected will be transitioned to the removed state R. We assumed a mean time to isolation after start of the infectious period (1/ϕ, where 0 < 1/ϕ < 1/γ). The model has a stochastic process where the infection dynamics is determined using the following system of Ordinary Differential Equations.