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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.