Table 4 Expanded compartments that considered both virus characteristics and interventions

Social distancing, wearing masks, washing hands, etc

U

Unsusceptible ^a(U)

[43]

Quarantined at home/hospitalization

S_T

Susceptible persons removed from isolation ^b(S_T)

[44]

I₂

Infectious after receiving ineffective treatment (I₂)

[45]

Q, D

Home quarantined individuals (Q), diagnosed individuals who are being treated and isolated (D)

[46]

I_a, I_s, Q_a, Q_s, R_u, R_a, R_s

Undetected asymptomatic infectious (I_a), undetected symptomatic infectious (I_s), detected and quarantined asymptomatic (Q_a), detected and quarantined symptomatic (Q_s), undetected recovered asymptomatic (R_u), recovered detected asymptomatic (R_a), recovered detected symptomatic (R_s)

[37]

W₁, R₁, D₁, W₂, R₂, D₂

Hospitalized that never require an intensive care

bed (W₁), recovered from non-ICU (R₁), deaths from non-ICU (D₁), hospitalized that require an intensive care

bed (W₂), recovered from ICU (R₂), deaths from ICU (D₂)

[41]

H₁, H₂

Confirmed cases who are quarantined at home (H₁), confirmed cases who are hospitalized (H₂)

[40]

I_p, I_c

Primarily infected (I_p), chronically infected (I_c)^c

[47]

Vaccination, testing or contact tracing

A_C

Contact traced asymptomatic (A_C)

[48]

E_u, E_d

Undetected exposed (E_u), detected exposed (E_d)

[38]

S_u, S_v

Unvaccinated susceptible (S_u), vaccinated susceptible (S_v)

[42]