Contagiousness

Relative contagiousness relative to severely sick cases

	Late incubation period [%] determines how contagious cases are during the last stages of latency. The contagiousness is given as a value which is realtive to the the average contagiousness of a severely sick patient during the infectious period (i.e. after latency). The contagiousness during the last stages of latency is kept constant in the model (i.e. it does not change form one stage to the next).
	Asymptomatic cases [%] determines how contagious infected individuals with asymptomatic course are on average during the infectious period (i.e. after latency). The contagiousness is given as a value which is realtive to the the average contagiousness of a severely sick patient during the infectious period (i.e. after latency). A value of 100% means that inidividuals with asymptomatic course are equally contagious as severely sick individuals. A value of 50% means that individuals with asymptomatic course are only half as contagious as severely sick indididuals.
	Moderately sick cases [%] determines how contagious moderately sick individuals are on average during the infectious period (i.e. after latency). The contagiousness is given as a value which is realtive to the the average contagiousness of a severely sick patient during the infectious period (i.e. after latency). A value of 100% means that severely sick cases are equally contagious as moderatly sick cases. A value of 50% means that moderately sick cases are only half as contagious as severely sick cases. A value of 200% means that moderately sick cases are twice as contagious as severely sick cases. The here supplied average degree of contagiousness does not distinguish between severe cases who are taken care of at home and others who are hospitalised.

Parameter settings

We are not aware of published results for the value of Late incubation period [%] (see below).

Cross-references

	The "average degree of contagiousness" is the arithmetic mean of the contagiousness which changes during the course of disease from one stage to the next.
	Changed values of the average contagiousness can only re-distribute the contagiousness, but cannot generally increase or lower the contagiousness of the pathogen (the user-supplied basic reproduction number, which summarizes the total contagiousness, must at all times be kept valid).
	Antiviral treatment can reduce the contagiousness of a case. As treatments are only given after seeking medical help, a high Late infectious period [%] can compromise the treatment effects.

Literature

	Late infectious period [%]: We are not aware of published results for the value of this parameter. Concerning the pre-set values, we have decided to use the same value as for asymptomatic cases.
	Asymptomatic cases [%] and Moderately sick cases [%]: Longini IM Jr, Halloran ME, Nizam A, Yang Y. Containing pandemic influenza with antiviral agents. Am. J. Epidemiol. 2004; 159: 623-633.

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