Skip to main content

Table 1 CystiAgent model parameters and plausible ranges used in sensitivity analyses

From: Understanding transmission and control of the pork tapeworm with CystiAgent: a spatially explicit agent-based model

Parameter Code Distribution Value Plausible range Source
Lower Upper
Village setup
 Humans per household humans-per-hh Poisson 3.89 3.32 4.94 RST
 Proportion of households raising pigs prop-pig-owners Binomial 0.49 0.25 0.75
 Pigs per pig-raising household pigs-per-hh Exponential 2.44 1.74 4.21
 Corral prevalence among pig-owner households prop-corrals Binomial 0.5 0.23 0.92
 Latrine prevalence prop-latrines Binomial 0.64 0.19 0.97
Pig trade
 Pig slaughter age (median) slaughter-age Log-normal 9.8 months 9.5 10.0 RST
 Proportion of pigs sold prior to slaughter pigs-sold Binomial 0.51 0.33 0.75 HH
 Proportion of sold pigs exported pigs-exported Binomial 0.73 0.34 1 HH
 Rate of pigs imported from endemic areas (imports/pig/week) pig-import-rate Uniform 0.00105 0 0.00384 HH
 Prevalence of cyst infection among imports import-prev Binomial 0.134 0 0.3 [18]
 Proportion of infected imported pigs with light cyst burden light-to-heavy Binomial 0.76 0.5 1 [18]
Pork consumption
 Proportion of pork consumed by owner hh-only-pork Binomial 0.40 0.22 0.71 HH
 Proportion of pork sold after slaughter sold-pork Binomial 0.12 0 0.5 HH
 Proportion of shared pork eaten by owner shared-pork-hh Binomial 0.8 0 0.84 HH
Human infection
 Incubation time to reach tapeworm maturity tn-incubation Fixed 8 weeks - - [27, 28]
 Tapeworm lifespan (mean, SD = 1 year) tn-lifespan Normal 2 years 0.5 4
Travel
 Proportion of households with a frequent traveler traveler-prop Binomial 0.42 0.24 0.65 HH
 Frequency of travel to other endemic areas (every × weeks) travel-freq Uniform 8 weeks 5 16 HH
 Duration of travel travel-duration Exponential 1.75 weeks 0.84 3.36 HH
 Incidence of T. solium taeniasis during travel (risk/person/week) travel-incidence Uniform 0.00023 0.00004 0.002 [18]
Open defecation
 Latrine-use (prop. of households that “always” use latrine) latrine-use Binomial 0.25 0 0.86 GPS
 Radius of environmental contamination (median, meters from home) cont-radius Log-normal 26 meters 23 30 GPS
 Rate of egg decay in environment (mean survival duration) decay-mean Exponential 8 weeks 1 26 [29]
Foraging
 Proportion of pig households with corrals that “always” corral pigs corral-always Binomial 0.05 0 0.39 GPS
 Proportion of pig households with corrals that “sometimes” corral pigs corral-sometimes Binomial 0.57 0.25 0.61
 Proportion of pigs in “sometimes”-corral-households that are corralled prop-corral-some Binomial 0.32 0.15 0.44
 Radius of pig roaming “home-range” (median) home-range Log-normal 44 meters 30 96
Tuning parametersa
 Probability of human taeniasis upon slaughter of lightly infected pig pl2h Binomial 0.0163 0.03 0.4 CAL
 Probability of human taeniasis upon slaughter of heavily infected pig ph2h Binomial 0.0046 0.003 0.04
 Probability of light cyst infection upon contact with T. solium eggs light-inf Binomial 0.0074 0.003 0.02
 Probability of heavy cyst infection upon contact with T. solium proglottids heavy-inf Binomial 0.0059 0.003 0.02
 Probability of exposure to T. solium eggs per human with taeniasisb light-all Binomial 0.0141 0 0.05
 Probability of exposure to T. solium proglottids per human with taeniasisb heavy-all Binomial 0.0182 0 0.05
  1. aListed values for tuning parameters were calibrated to a single test village used to assess baseline model function in Fig. 2
  2. bExposure probabilities (“light-all” and “heavy-all”, x) scaled to the current number of tapeworm carriers (HT) according to 1 − (1–x)HT
  3. Abbreviations: HH, Household survey; GPS, GPS pig tracking study, RST, Ring Strategy; CAL, calibration; SD, standard deviation