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Swedberg et al. One Health Implement Res 2023;3:77-96 https://dx.doi.org/10.20517/ohir.2023.02 Page 89

Table 4. Decision tree model estimates and recorded data for the annual burden of rabies in Oriental Mindoro Province
Year 2020 2021 2022
Recorded deaths (PHO) 9 7 9
Estimated deaths 10 7 10
[9-12] [7-10] [9-13]
Estimated exposures 198 149 302
[133-258] [91-210] [192-408]
Estimated exposures not given PEP 61 42 61
[55-73] [42-61] [55-79]
Estimated exposure incidence per 100,000 22 16 33
[15-28] [10-23] [21-45]
Laboratory-confirmed animal cases (RADDL) 3 7 18
Estimated rabid dogs 510 388 781
[322-715] [217-581] [477-1,090]
Estimated % confirmed animal cases 0.59% 1.81% 2.3%
[0.42-0.93] [1.2-3.23] [1.65-3.77]
Estimated rabid dogs per 1,000 dogs 3.46 2.57 5.3
[1.55-6.59] [1.08-5.43] [2.27-10.27]
Median values are shown together with 95% prediction intervals in brackets. Recorded human deaths are from the PHO and animal case data
from the RADDL. PEP: Post-exposure prophylaxis; PHO: Provincial Health Office; RADDL: Regional Animal Disease Diagnostic Laboratory.

Decision tree estimates revealed considerable variation in rabies burden and surveillance performance by
municipality [Table 5]. The estimated exposure incidence ranged from 4 to 59 people per 100,000 who were
potentially exposed to rabies each year across the 15 municipalities. Animal surveillance was weak, with the
number of recorded human deaths (25 total) over 3 years nearly matching the number of confirmed animal
cases (28 total). In 12 of the 15 municipalities, < 2% of estimated animal cases were detected, with four
municipalities not submitting any samples for diagnostic testing. Notably, the two municipalities with the
highest animal case detection, Baco (13.7%) and Puerto Galera (4.1%), did not record any human rabies
deaths.

From the sensitivity analysis [Figure 4], the parameters that had the greatest impact on estimates of human
rabies exposures and P seekPEP were the number of high-risk bites, followed by the probability of observing
human deaths (P obs|death ). The probability of a rabid dog biting (P bites|rabid_dog ) and the number of high-risk bite
patients most influenced estimates of rabid dogs.

Economic analysis of PEP policies and costs
We calculated an average PEP cost of $51.44 USD per person ($37.50 USD for those receiving vaccine only,
and $127.50 USD for those also receiving ERIG), based on the assumption that each patient received an
average of six 0.1 mL ID injections of post-exposure vaccine, and that 79.6% of Category III bites (15.5% of
total bite patients) received ERIG, with an average of 2 vials of ERIG each. This translates to total costs
(human rabies vaccine and ERIG) ranging between $445,185 and $734,280 USD annually and over $1.74
million USD during the 3-year study period (2020-2022) in Oriental Mindoro.

We estimated that PEP prevented between 20 and 43 deaths (95% PrI 3-72) per year in Oriental Mindoro at
an average cost of $20,190 USD (95% PrI $11,565-79,400) per death averted. Using the mean age of death
during our study period (35 years), we estimated an average of 1,105 DALYs averted annually, costing $527
USD per DALY averted. If PEP were administered solely to high-risk and unknown-risk bite patients
during the 3 years (715 total), estimated costs would be approximately $17,050 USD annually for vaccine
(~$11,920 USD) and ERIG (~$5,130 USD), assuming a full vaccine course (8-ID injections) and all