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Page 88 Swedberg et al. One Health Implement Res 2023;3:77-96 https://dx.doi.org/10.20517/ohir.2023.02

Figure 3. IBCM risk assessment and rabies case data from Oriental Mindoro Province. (A) Time series from January 2020 to December
2022, showing IBCM bite patient data by risk category: low-risk (gray), unknown-risk (orange), and high-risk (red); (B) Maps showing
the incidence of high-risk bites per 100,000 persons from IBCM risk assessments by municipality (red shading) and locations where
exposure events occurred for human rabies cases (black dots) and where confirmed animal cases were found (red dots) by year: 2020,
2021, and 2022. IBCM: Integrated Bite Case Management.

Decision tree estimates of rabies burden and surveillance performance
From the decision tree model [Figure 2], we estimated that an average of 216 people (95% PrI 91-408) were
exposed to rabies annually in Oriental Mindoro [Table 4], with an average of 55 (95% PrI 42-79) not
reporting to health facilities for PEP, i.e., people exposed to rabies sought PEP with probability 0.738 (95%
PrI 0.594-0.811), assuming 90% of rabies deaths are recorded (i.e., P obs|death = 0.9). Under this same
assumption, around 27 (95% PrI 25-35) human deaths were estimated to have occurred over the 3 years (in
comparison to the 25 deaths recorded). While the PHO records [Table 3] indicate a high incidence
exceeding 1,240 bite patient presentations per 100,000 people per year, we estimated an annual incidence of
24 (95% PrI 10-45) exposures and 0.77-1.1 deaths per 100,000 people [Table 4].

We estimated there were an average of 560 (95% PrI 217-1,090) rabid dogs per year in Oriental Mindoro,
from an estimated dog population of 140,420 (95% PrI 92,340-289,950), equating to 3-5 rabid dogs per 1,000
dogs/year. These estimates suggest that surveillance only detected between 1%-2% of animal cases during
the study period. Though low, animal surveillance performance in terms of laboratory-confirmed cases
increased almost fourfold from 2020 to 2022 (from 0.59% to 2.3%) through implementing IBCM. However,
this increase in case detection may also indicate higher incidence in 2022 compared to 2020, rather than
improved surveillance performance.