Innovative Rabies Control: Insights from One Health Surveillance in Albay, Philippines
Aug 28, 2024
2024/8/26
A recent study titled “One Health Surveillance for Rabies: A Case Study of Integrated Bite Case Management in Albay Province, Philippines” highlights the potential for a more effective approach to controlling rabies outbreaks through Integrated Bite Case Management (IBCM). By combining human bite incident data with field investigations of suspect animals, the study achieved a significant increase in rabies detection over a 13-month period.
1. The study observed a fourfold increase in rabies case detection in Albay province using IBCM compared to traditional surveillance methods. This approach also fostered stronger collaboration between public health and veterinary sectors, illustrating the One Health ethos in action.
2. A high incidence of bite cases was recorded in Albay, with over 600 bite patient presentations per 100,000 people annually. Post-exposure prophylaxis (PEP) was commonly administered, but the indiscriminate use of vaccines resulted in unnecessary expenditure, as only 3% of these cases were confirmed or probable rabies exposures.
3. Dog vaccination rates in the region remained low (41% on average), with the majority of vaccination campaigns concentrated in urban areas. The proximity of villages to Animal Bite Treatment Centers (ABTCs) strongly influenced both patient attendance and vaccination efforts.
4. The study calls for enhanced surveillance and targeted rabies control measures, emphasizing that localized rabies transmission patterns should inform future vaccination campaigns.
Introduction
Rabies is a persistent public health issue in the Philippines, particularly in Albay province. Despite efforts to control the spread of rabies through dog vaccination campaigns and post-exposure prophylaxis (PEP), transmission remains a challenge. This study explores the potential of Integrated Bite Case Management (IBCM) as an innovative approach to improving rabies detection and controlling outbreaks. By focusing on a One Health model that bridges human and veterinary health sectors, the researchers sought to foster intersectoral collaboration and improve the efficiency of rabies surveillance in the region.
This research is timely, given the rising burden of rabies in Southeast Asia and the global commitment to eliminating human rabies deaths by 2030. The study provides valuable insights into how rabies control measures can be optimized by integrating bite case data with animal investigations, ultimately aiming for more sustainable, cost-effective interventions.
Method
This longitudinal study, conducted from March 2018 to March 2019, covered 13 months of rabies surveillance in Albay province. The province has a population of over 1.3 million people and 161,478 dogs, based on data from the Philippine Statistics Authority and Albay Provincial Veterinary Services. The researchers implemented Integrated Bite Case Management (IBCM) at three government-run Animal Bite Treatment Centers (ABTCs) in the region, where bite victims were interviewed and followed up after receiving PEP.
Bite incident data was collected from standardized registers maintained by nurses at the ABTCs. The data was supplemented by phone follow-ups with bite victims to assess the health condition of the biting animals. Field investigations were triggered when animals displayed rabies symptoms, died, or were untraceable during the 14-day quarantine period. Investigated cases were classified as “Healthy,” “Non-traceable,” “Rabies suspect,” “Rabies probable,” or “Rabies confirmed.”
The study analyzed both human bite incident data and dog vaccination records to assess the relationship between vaccination coverage, clinic proximity, and rabies transmission patterns. Regression models were used to estimate the predictive value of bite case data for future rabies occurrence, and spatial mapping tools were employed to visualize bite incidence and vaccination coverage across the province.
Result
1. Enhanced Rabies Detection through IBCM
The study revealed that Integrated Bite Case Management (IBCM) dramatically increased the detection of rabies cases. Over the 13-month period, rabies detection increased fourfold, with 49 confirmed cases identified compared to only 12 in the prior period. The increase was largely attributed to the field investigations triggered by bite incident data and phone follow-ups. Rabid dogs were typically located within 1 km of their homestead, indicating that rabies transmission occurred locally and was spatially clustered.
Field investigations prompted by rabies-suspected animals were critical in uncovering additional cases that would otherwise have gone undetected. Of the 256 incidents classified as “Rabies probable,” 33 were subjected to further investigation, leading to 22 laboratory-confirmed cases of rabies. This demonstrated the value of IBCM in improving surveillance and enabling faster outbreak responses, particularly in hard-to-reach rural areas.
The study also highlighted the importance of quarantine protocols and community participation in rabies detection. Bite victims were encouraged to monitor their pets for 14 days and report any changes in behavior, contributing to timely interventions. The fourfold increase in case detection underscores the effectiveness of IBCM in strengthening rabies surveillance.
2. Bite Incidence and Vaccination Patterns
Bite incidence in Albay was notably high, with over 600 patient presentations per 100,000 people per year. Most of these cases involved dog bites (90%) and were concentrated in barangays close to ABTCs, suggesting that clinic proximity played a significant role in health-seeking behavior. However, only 3% of bite cases were classified as “Rabies probable” or confirmed, indicating that many patients received PEP unnecessarily.
Dog vaccination rates varied widely across the province, with an average coverage of 41%. Urban areas with high population density achieved higher vaccination rates, while rural barangays further from ABTCs had lower coverage. This uneven distribution of vaccines was reflected in rabies transmission patterns, as barangays with low vaccination coverage reported higher numbers of rabies cases.
Regression analysis confirmed that both patient attendance at ABTCs and dog vaccination rates were negatively correlated with the distance to clinics. This finding highlights the importance of making vaccination campaigns more accessible in rural areas to improve rabies control. Effective rabies prevention requires both high vaccination coverage and equitable access to clinics for bite victims.
3. Cost-Efficiency and Policy Recommendations
The study identified significant inefficiencies in PEP administration, with vaccines often provided unnecessarily. Despite WHO guidelines recommending PEP only for high-risk exposures, the majority of bite patients received vaccines, contributing to substantial financial strain. The researchers estimated that over $200,000 was spent on rabies immunoglobulin (RIG) during the study period, funds that could have been used for mass dog vaccination campaigns.
The data suggested that reserving RIG for Category III patients with multiple exposures could reduce costs and free up resources for rabies control efforts. Moreover, the study found that proactive rabies detection through IBCM could inform better vaccine allocation, targeting high-risk areas for both dog vaccination and human PEP.
Based on these findings, the researchers recommend expanding IBCM as a cost-effective tool for rabies detection and control. Additionally, increasing dog vaccination coverage, particularly in rural barangays, is crucial to preventing outbreaks. Optimizing vaccine use and enhancing surveillance can reduce unnecessary expenditures while improving rabies control outcomes.
Conclusion
The study demonstrates that Integrated Bite Case Management (IBCM) is a valuable strategy for improving rabies detection and optimizing resource use in rabies-endemic regions. By combining human bite case data with animal investigations, IBCM can enhance surveillance, reduce unnecessary PEP administration, and inform targeted vaccination campaigns. Expanding this approach, particularly in rural areas, is essential for achieving the global goal of eliminating dog-mediated human rabies deaths by 2030.
Paper URL: https://doi.org/10.3389/fitd.2022.787524
