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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 87

Table 3. Characteristics of bite patients and human deaths from PHO records before the study (2019) and during the study period
(2020 to 2022)

Year 2019 2020 2021 2022 Average per study year (2020-2022)
pre-study
Recorded human deaths 5 9 7 9 8
Total bite patients 9,217 8,370 11,269 14,308 11,316
Mean monthly patients 768 698 939 1,192 943
Bite incidence per 100 k 1,015 921 1,241 1,575 1,246
% male 49.5 49.9 48.2 47.6 48.4
Bites U15yrs (%) 3,781 (41) 3,548 (42.4) 5,065 (44.9) 5,714 (39.9) 4,776 (42.2)
Category I (%) 106 (1.2) 307 (3.7) 26 (0.2) 30 (0.2) 121 (1.1)
Category II (%) 7,322 (79.4) 6,257 (74.8) 9,189 (81.5) 11,535 (80.6) 8,994 (79.5)
Category III (%) 1,789 (19.4) 1,806 (21.6) 2,054 (18.2) 2,743 (19.2) 2,201 (19.5)
ERIG (% of Category III) 1,445 (80.8) 1,459 (80.8) 1,603 (78) 2,197 (80.1) 1,753 (79.6)
Dog bite (%) 6,311 (68.5) 5,947 (71.1) 7,768 (68.9) 9,289 (64.9) 7,668 (67.8)
Cat bite (%) 2,744 (29.8) 2,352 (28.1) 3,429 (30.4) 4,912 (34.3) 3,564 (31.5)
Bite by other animal (%) 162 (1.8) 71 (0.8) 72 (0.6) 107 (0.7) 83 (0.7)
ERIG: Equine rabies immunoglobulin; PHO: Provincial Health Office.

Extrapolating the proportion of high-risk bites from IBCM data (2.5%) to total bite patients in the province
(33,947), we estimate 838 high-risk bites over 3 years, with an average of 279 per year. One ABTC, located in
a major hospital in Calapan, reported nearly complete data during the study. These data represented 47.9%
(6,055/12,640) of IBCM records, with 0.96% of bites assessed to be high-risk (3.7% for high-risk + unknown-
risk). Using these proportions for comparison with incomplete IBCM data, we estimated 325 high-risk bites
over 3 years and an average of 108 per year. When assuming only dog bites are high-risk, based on RADDL
records which found no cats tested positive over the last 5 years, we estimate 2.8% (240/8,701) of bites to be
high-risk (5.2% for high-risk + unknown-risk, 449/8,701).

Over the course of the 3 years (2020-2022), 25 human deaths were formally investigated and recorded as
probable rabies cases in Oriental Mindoro Province, and 28 animal cases were confirmed with DFA. Death
investigations, conducted by a team of PHO and/or DOH staff, involved clinical diagnosis using hospital
records and interviews with medical staff and the patient’s family. No samples were collected for testing.
Deaths ranged in age from 4 to 69 years (median = 37 years), with 6 (25%) being under 15 years old and a
male:female ratio of 1.08:1. Exposure events leading to human infection then death were concentrated in 8
of the 15 municipalities [Figure 3B], with 64% occurring in just three municipalities (Bongabong-6,
Mansalay-5, and Pinamalayan-5). The most densely populated area, the capital city of Calapan, had zero
human rabies deaths but had two animal cases confirmed over the study period.

For all reported human rabies cases, the biting animal was a dog. Of the confirmed animal cases, 54%
(15/28) were found in three municipalities (Baco-7, Mansalay-4, and Puerto Galera-4), of which two (Baco
and Puerto Galera) reported zero human rabies deaths during the study period. None of the human cases
received PEP prior to displaying symptoms of rabies infection. As per PHO death investigation reports,
primary reasons for not seeking PEP after exposure events included: a lack of awareness of the risk of rabies
from animal bites, the choice to consult traditional healers for treatment (known as tandok/tawak in the
Philippines), and financial constraints preventing the ability to cover travel costs and take time off work to
seek PEP, particularly for those in remote locations relying on agricultural work.