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Table 4 List of the model stochastic transitions and their rates

From: The role of hand hygiene in controlling norovirus spread in nursing homes

Events Transitions Rates
1- Resident admission to the NH S R  → S R  + 1 μ × N R
2- Susceptible resident discharge out of the NH (or death) S R  → S R  − 1 μ × S R
3- Susceptible resident exposed to the virus S R  → S R  − 1 & E R  → E R  + 1 R  = p × [(1-h RR ) × C RR ×(I R  + α × E R  + α × A R ) + (1-h SR ) × C SR ×(I S  + α × E S  + α × A S )]
4- Exposed resident discharge out of the NH (or death) E R  → E R -1 μ × E R
5- Start of symptoms in exposed residents E R  → E R -1 & I R  → I R  + 1  × E R
6- Infected symptomatic resident discharge out of the NH (or death) I R  → I R -1 μ × I R
7- Asymptomatic resident discharge out of the NH (or death) A R  → A R -1 μ × A R
8- End of symptoms in residents I R  → I R -1 & A R  → A R  + 1 σ × I R
9- Recovery of an asymptomatic resident A R  → A R -1 & R R  → R R  + 1 ρ × A R
10- Recovered resident discharge out of the NH (or death) R R  → R R -1 μ × R R
11- Immunity loss of a resident R R  → R R -1 & S R  → S R  + 1 θ × R R
12- Susceptible staff member exposed to the virus S S  → S S -1 & E S  → E S  + 1 S  = p × [(1-h SS ) × C SS ×(I S  + α × E S  + α × A S ) + (1-h SR ) × C SR ×(I R  + α × E R  + α × A R )]
13- Start of symptoms in exposed staff members Ep → E S -1 & Ip → I S  + 1  × E S
14- End of symptoms in staff members I S  → I S -1 & A S  → A S  + 1 σ × I S
15- Recovery of an asymptomatic staff member A S  → A S -1 & R S  → R S  + 1 ρ × A S
16- Immunity loss of a staff member R S  → R S -1 & S S  → S S  + 1 θ × R S
  1. S R and S S respectively number of susceptible residents and staff members
  2. E R and E S respectively number of exposed residents and staff members
  3. I R and I S respectively number of infected symptomatic residents and staff members
  4. A R and A S respectively number of asymptomatic residents and staff members
  5. R R and R S respectively number of recovered residents and staff members
  6. μ admission and discharge rate
  7. p per-contact probability of transmission
  8. C RR contact rate resident-resident
  9. C SR contact rate staff-resident
  10. C SS contact rate staff-staff
  11. h RR hand hygiene compliance rate during resident-resident interactions
  12. h SR hand hygiene compliance rate during staff-resident interactions
  13. h SS hand hygiene compliance rate during staff-staff interactions
  14. α Relative infectiousness of A and E individuals
  15. 1/ Duration of incubation
  16. 1/σ Duration of symptoms
  17. ρ Recovery rate
  18. θ Rate of immunity loss