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Page 84              Swedberg et al. One Health Implement Res 2023;3:77-96  https://dx.doi.org/10.20517/ohir.2023.02

               Table 1. Parameters and data used in the decision tree model
                                                        Point estimate/range  Range used for
                Definition       Parameter Distribution/Data                               Source
                                                        for main model   sensitivity analyses
                Probability of developing   P  Binomial  0.165           0.124-0.206       [25]
                                  rabies|exposure
                rabies after exposure in
                the absence of PEP
                Average number of   P bites|rabid_dog  Negative binomial  μ = 0.3862   μ = 0.15-0.50   [26]
                persons bitten per rabid                k = 0.7055       k = 0.7055        Ferguson, E. pers.
                dog                                                                        comm.
                Probability of human   P obs|death  Binomial  0.90       0.5-1.0           Assumption, based on
                rabies death being                                                         discussion with
                recorded in official                                                       stakeholders
                records
                Rabies exposures   E PEP  IBCM data     High-risk bite patients -   high-risk dog bite   IBCM data (see text
                receiving PEP                           (high-risk + unknown-risk) patients/2 - (high-risk +   for details)
                                                                         unknown risk bite patients)
                Human:dog ratio for   HDR  Uniform      3-10             3-10              [27,28]
                Oriental Mindoro

               HDR: Human:dog ratio; IBCM: Integrated Bite Case Management; PEP: post-exposure prophylaxis.

               people bitten per rabid dog, P bites|rabid_dog . Details of calculations are described below and outlined in Figure 2.


               Parameter estimates
               Parameters for the model used government or IBCM data from the Philippines to reflect local context
               where possible [Tables 1 and 2]. When national or regionally specific data were not available, we used
               probabilities from the literature, including P rabies|exposure  and P bites|rabid_dog  calculated from contact tracing data
               from Tanzania [25,26] .

               We estimated the probability of rabies-exposed bite victims seeking PEP (P seekPEP ) from the probability of
               developing rabies following exposure in the absence of PEP (P rabies|exposure ), IBCM risk assessments, and
               observed rabies deaths (D observed ). We assumed deaths were observed with high probability (P obs|death ):
               D  = D  observed /P obs|death .
                 Total

               To estimate total exposures (E ), we summed estimates of exposures who did not seek PEP (E no_PEP ) with
                                         Total
               exposures who did (E ) derived from the IBCM risk assessments:
                                 PEP
               E no_PEP  = D  / P rabies|exposure
                        Total
               E  = E no_PEP  + E PEP
                Total

               P seekPEP  was calculated from the estimates of total exposures and exposures that did not seek PEP
               (P  = E no_PEP /E ), while deaths averted (D averted ) were estimated from rabies-exposed patients who sought
                            Total
                 seek
               PEP and the probability of developing rabies following exposure in the absence of PEP: D averted  = E  ×
                                                                                                      PEP
               P rabies|exposure .
               The dog population was estimated from the human population as recorded in the national census ,
                                                                                                       [18]
               divided by the human:dog ratio (HDR). A range of HDRs were extracted from published studies in the
               Philippines [27,28] . Rabid dogs were estimated from total exposures (E ) divided by P bites|rabid_dog  and annual
                                                                          Total
               rabies incidence per 1,000 dogs calculated. The percentage of rabid dogs that were laboratory-confirmed out
               of the estimated total rabid dogs was calculated from RADDL data.
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