Shigellosis Dynamics: Modelling the Effects of Treatment, Sanitation, and Education in the Presence of Carriers

Table 2

Parameters and their description.

Parameter	Description	Value	Source
	Rate of recruitment of individuals into the susceptible class	462 humans/year	[19]
	Transmission rate for infectious individuals	/year	[19]
	Transmission rates for carriers	0.6/year	[19]
	Effective transmission rate of Shigellosis due to environment to human interaction	0.4465/year	[17]
	Incubation rate (rate at which exposed individuals, , progress to either class or )	0.35/day	[18]
	Natural human mortality rate	0.4465/year	Assumed
	A fraction of exposed individuals, , who progress to class	0.9	[18]
	A fraction of carriers, , who recover naturally and progress to class	0.4	Assumed
	Rate of screening carriers	0.56	Assumed
	Disease-induced death rate by	0.02/year	Assumed
	Recovery rate of infectious humans	0.14/day	[16]
	Recovery rate of carrier humans	0.0286/day	[18]
	The environmental carrying capacity for Shigella bacteria in the food or water supply	cells/mL	Assumed
	Half-saturation rate of Shigella bacteria that can cause a 50% chance of infection	60 cells/mL	Assumed
	Bacteria shed rate into the water supply by infectious human	80 cells/mL/day	[20]
	Bacteria shed rate into the water supply by carrier humans human	70 cells/mL/day	[20]
	Maximum per capita growth rate of Shigella bacteria	0.73/day	[21]
	Mortality rate of Shigella bacteria, including phage degradation	0.83/day	Assumed
	Waning rate of disease-induced immunity	0.25/year	[16]
	Rate at which sanitation leads to death of Shigella bacteria	/year	[22]
	Treatment rate for infectious individuals (I)	0.4/year	Assumed
	Education efficacy parameter	0.6/year	[21]