TABLE 1.
Parameter definitions and values
| Parameter | Definition | Value or distributiona | References or additional information |
|---|---|---|---|
| j | Incidence of (symptomatic) cholera in peacekeepers' country of origin | Unif(0.1,8) per 1,000 people per year | 3, 30; see supplemental material for details |
| rR | Proportion of DR cholera in country of origin | Unif(0,0.5) | 12–14 |
| R0 | Basic reproductive number in the absence of treatment or vaccination | Unif(1.25,5) | 31, 32 |
| σ | Proportion of cholera infections that are symptomatic | Beta(242,706) | Symptom probability in Haiti survey 0.255 (0.228, 0.284) (33); similar point estimate (0.242) in meta-analysis of reference 3 |
| τprop (rate = τ) | Proportion symptomatic who receive treatment | Unif(0.05,0.5) | 18, 34–37; see supplemental material for details |
| aprop (rate = a) | Proportion receiving treatment or prophylaxis who acquire resistance | 10^Unif(−5,−2) | 19, 20, 38–40; see supplemental material for details |
| Nimp | Number of peacekeepers | 500 | Assumed; similar to number in Haiti (3) |
| N | Population size | 1,000,000 | Assumed; 10,000 also tested (see supplemental material) |
| 1/γ | Average duration of infection (untreated) | 5 days | 3 (we made the simplifying assumption that this was the same for asymptomatic and symptomatic infections), 41 |
| 1/γabx | Average duration of infection (treated) | 2.26 days | 3, 41 |
| vabx | Risk ratio of DS infection given antibiotic chemoprophylaxis | 0.34 | 3, 42; see supplemental material for sensitivity analyses |
| βa/β | Relative infectiousness of asymptomatic infections | 10% | 3, 43, 44; see supplemental material for additional details and results based on 1% and 50% |
| 1/δ | Incubation period | 1.55 days | 3, 45 |
| σvaxm | Multiplier: relative probability of symptoms among vaccinated individuals (vs unvaccinated) | 0.35 | Protective efficacy in older children and adults is 0.66 (0.57, 0.73) (46) |
| βvaxm | Multiplier: relative infectiousness of vaccinated asymptomatic individuals (vs unvaccinated asymptomatic) | 0.37 | Assuming a log-linear relationship between infectiousness and vibrio density (6); see supplemental material for details and sensitivity analyses |
a
Unif, numbers are drawn according to a uniform distribution with the provided max and min; 10^Unif, the exponent of 10 is drawn according to a uniform distribution with the provided max and min.