Networks of necessity: Simulating COVID-19 mitigation strategies for disabled people and their caregivers
Fig 3
A schematic illustration of our compartmental model of disease transmission.
Susceptible individuals (S), by being exposed to asymptomatic (A) or symptomatically ill (I) individuals, can become exposed (E) with a baseline transmission probability β. One can reduce the risk level of an interaction through the NPI of mask-wearing; this multiplies the risk level by the factor m1/2 (if only one individual in the interaction wears a mask) or the factor m (if both individuals in the interaction wear a mask). Caregiving interactions have a higher risk level (by a factor wc) than the baseline and weak interactions have a lower risk level (by a factor ww) than the baseline. Exposed individuals are not yet contagious; however, they can eventually transition to the asymptomatic state. From the asymptomatic state, an individual can either become symptomatically ill or be removed (R), which encompasses recovery, death, and any other situation in which an individual is no longer infectious. If an individual is symptomatic, they can either be removed or become hospitalized (H). From the hospitalized state, an individual eventually transitions to the removed state. The state-transition parameters that we have not yet mentioned are fixed rates of exponential processes.