In the fight against rabies—a deadly disease claiming approximately 70,000 human lives each year worldwide—new research from Peru offers groundbreaking insights into the challenges faced in tracking and controlling this ancient scourge. Led by Dr. Ricardo Castillo of the University of Pennsylvania’s Perelman School of Medicine, this study sheds light on socio-economic disparities affecting rabies surveillance systems in Arequipa, Peru’s second-largest city, with implications far beyond its borders.
Rabies, a viral zoonotic disease primarily transmitted through dog bites, was believed to have been eradicated in Peru for many years. However, recent re-emergence of canine rabies has reignited concerns about public health, especially in lower-income communities where the disease has been observed at disproportionately higher rates. The disease’s near-exclusive association with dogs—accounting for 99% of all transmitted cases globally—underscores the urgency to monitor canine populations effectively to mitigate the risk to humans.
Despite the critical need, Peru’s conventional rabies surveillance relies heavily on passive reporting methods. These systems depend on community members alerting local health authorities about deceased or suspiciously behaving dogs. In theory, passive surveillance should provide sufficient data on rabies incidence, but Dr. Castillo and his team found significant gaps in this approach. Poorer neighborhoods often remain under-represented due to structural barriers such as fewer nearby medical and veterinary facilities, limited awareness of rabies’ dangers, economic constraints, and a predominance of informal employment that limits residents’ availability to engage with health services.
Recognizing this disparity, the research team implemented an active surveillance strategy starting in 2021, marking a shift from reliance on community reports to proactive fieldwork. Partnering with Cayetano Heredia University in Lima, researchers combed through Arequipa’s dry water channels—known hotspots where deceased dogs often congregate—to identify cases missed by passive systems. This multidimensional approach significantly enhanced case detection, with active surveillance accounting for roughly one-third of all collected samples during 2021 and 2022.
The research went beyond mere data collection; it sought to elucidate spatial and socio-economic patterns associated with rabies incidence and sampling coverage. Each city block in Arequipa was assigned a socioeconomic rank from A to E based on average household incomes, with A representing the wealthiest and E the poorest. Intriguingly, while passive surveillance predominantly collected samples from mid to low-income areas (levels D and E), active surveillance was even more heavily focused in these underprivileged zones, with over 78 percent of samples originating there in the years examined.
The findings reveal a disconcerting mismatch: neighborhoods most at risk for canine rabies, often low-income blocks, are those least visible within traditional surveillance frameworks. This problem is exacerbated by geographic and social inequities that hinder efficient rabies tracking and control, effectively allowing the disease to persist beneath the radar in vulnerable populations. Structural inequities are not merely logistical challenges; they represent a critical public health vulnerability that may undermine eradication efforts.
Globally, this research holds vital lessons for rabies control and broader zoonotic disease surveillance. Rabies remains endemic in many parts of the Caribbean, Africa, and Asia, where unequal access to health infrastructure similarly hampers effective outbreak responses. Importantly, even developed countries face challenges. In the United States, for example, wildlife reservoirs such as raccoons in the Northeast and skunks in southern regions pose continual risks, compounded by urban socio-economic segregation and neglected feral animal populations parallel to those seen in Arequipa.
Federal funding from U.S. institutions, including the National Institute of Allergy and Infectious Diseases and the NIH-Fogarty International Center, was instrumental in establishing the active surveillance model in Peru. Such investments facilitate cross-border knowledge transfer, helping countries strengthen local disease control while contributing to global health security. Dr. Castillo emphasizes the interconnected nature of these challenges: “Rabies control is a shared health challenge. If it persists in one place, it remains a risk everywhere.”
The re-emergence of canine rabies in Arequipa exemplifies the complex interplay between infectious disease dynamics and social determinants of health. This study’s approach of integrating socio-economic data with spatial epidemiology represents a pioneering methodology with broad applicability. It calls upon public health officials worldwide to reconsider surveillance systems, advocating for equity-oriented designs that prioritize vulnerable communities to identify and address silent reservoirs of rabies and other zoonoses.
Technically, the active surveillance strategy incorporated systematic sampling from locations historically and environmentally likely to harbor infected animals rather than relying solely on voluntary human reporting. This shift mitigates inherent biases in passive systems, such as underreporting in marginalized areas. Success in Arequipa suggests active surveillance, combined with geospatial socioeconomic analysis, should be integrated into rabies control frameworks globally, especially in endemic settings where infrastructure disparities exist.
Moreover, this research underlines the importance of multidisciplinary collaboration, harnessing expertise from epidemiology, veterinary medicine, geography, and public health policy. It exemplifies how complex diseases that transcend species boundaries demand solutions that integrate animal health with human health under the One Health umbrella. Application of such integrated approaches in urban environments holds promise in preempting not only rabies outbreaks but also novel zoonotic threats exacerbated by climatic change and global migration trends.
In sum, the work emanating from Peru is a clarion call to refine disease surveillance systems, underscored by the principle of health equity. The persistence of rabies in marginalized urban sectors reveals structural vulnerabilities that can thwart even the most scientifically advanced control efforts if left unaddressed. With scientific rigor and targeted resource allocation, this study provides a replicable blueprint that could accelerate rabies elimination worldwide, moving closer to a future where this entirely preventable disease no longer claims lives.
Subject of Research: Animals
Article Title: [Not provided]
News Publication Date: [Not provided]
Web References:
- CDC Rabies Around the World: https://www.cdc.gov/rabies/around-world/index.html
- The Lancet Regional Health – Americas article DOI: http://dx.doi.org/10.1016/j.lana.2025.101285
References:
This study was supported by the National Institute of Allergy and Infectious Diseases (grant numbers K01AI139284 and R01AI168291) and the National Institutes of Health-Fogarty International Center (D43TW012741).
Keywords: Public health, Animal diseases, Disease outbreaks, Infectious diseases, Epidemiology
