The age-structured model, the symptom-compartment model and others don't stratify according to symptoms, so should use the infection fatality ratio not the case fatality ratio. This is because Verity et al. assume a case definition of "symptomatic or confirmed disease" whereas an infection definition that includes milder disease.
The age-structured model, the symptom-compartment model and others don't stratify according to symptoms, so should use the infection fatality ratio not the case fatality ratio. This is because Verity et al. assume a case definition of "symptomatic or confirmed disease" whereas an infection definition that includes milder disease.