Mathematical Modelling of COVID-19 Transmission in Kenya: A Model with Reinfection Transmission Mechanism

Table 2

Desription of model parameters.

Parameter	Description	Units
β	Effective contact rate (contact capable of leading to COVID-19 transmission)	Day^−1
	The fraction of the members of the public who correctly and consistently wear masks in public.	Day^−1
κ	Proportion of the population who strictly observe social/physical distance	Day^−1
	Modificationn parameters for the assumed reduction of infectiousness among infectious asymptomatic individuals, mild-symptomatic individuals and hospitalized individuals	Day^−1
q	Measure of efficacy of contact tracing of asymptomatic humans and hospitalization in preventing COVID-19 transmission 0≤q≤1	Day^−1
f	Proportion of exposed individuals who progress to infectious asymptomatic class after incubation period	Day^−1
(1−f)	Proportion of exposed humans who progress to a class of infectious individuals with mild symptoms after incubation period	Day^−1
	Intrinsic incubation period for individuals exposed to COVID-19	Day^−1
	Duration of COVID-19 protective immunity	Day^−1
	Rate at which infectious asymptomatic humans develop COVID-19 mild symptoms and move to Im class	Day^−1
α	Represents the rate at which infectious asymptomatic individuals are detected via contact tracing, tested and isolated at home (home-based care) or quarantined such that they have no contact with the susceptible humans	Day^−1
v	Rate at which infectious humans with mild symptoms develop severe symptoms and move to is class	Day^−1
	Respectively, represent recovery rates for individuals in the Ia, Im, H, Id classes	Day^−1
η1,η2	Respectively, represent the rate at which individuals with mild COVID-19 symptoms and individuals with severe COVID-19 symptoms are hospitalized	Day^−1
θ	Modification parameter accounting for partial protection against COVID-19 reinfection among individuals with weak or no protective immunity 0<θ≤1	Day^−1
da,dm,ds,dd,dh	Respectively represent COVID-19 induced mortality rates for individuals in the Ia,Im,Is,Id,H classes	Day^−1