Table 1 Description of model parameters for strong (first value) and weak (second value) interventions with rationale. Values of rate parameters c, v, \(q_s\), \(q_{pep}\), and \(q_i\) are per day
From: Measles in Canada: modelling outbreaks with variable vaccine coverage and interventions
Parameter | Value | Description | Reference or rationale |
|---|---|---|---|
\(\beta\) | 3.75e-4 (\(N=1000\)); 4.69e-5 (\(N=8000\)) | Transmission parameter | \(R_0\) usual range 12–18; estimate for Canada 28; this gives \(\sim 20\) with weak measures and \(v=0\) [14]. |
c | 0.3 | “Exposed” individuals are infectious before onset of rash | 4 days infectiousness prior to rash onset [10] |
v | 0.005; 0.003 | Supplementary vaccination of susceptibles. Not all jurisdictions strongly encourage additional vaccination in the general population as an outbreak response. | British Columbia vaccination in 2019 outbreak (rough estimate) [15] |
\(q_s\) | 0.06; 0.04 | Isolation of susceptible individuals following contact tracing, exposure notifications | See text |
\(q_{pep}\) | 0.1875; 0.0875 | Post-exposure prophylaxis (PEP) plus isolation rate if PEP declined | See text |
k | 1/12 | Progression to rash onset | Course of infection rash onset at 10–14 days [10] |
\(q_i\) | 0.4; 0.28 | Identification and isolation of symptomatic individuals | See text |
\(\gamma\) | 1/4 | Recovery from symptoms and infectiousness | Infectious until 4 days after rash onset [10] |