Epidemiology and Spatio-Temporal Dynamics of Plague in Ecuador (1908–2008)

Background: Plague is an infectious disease caused by the virulent Gram-negative bacillus Yersinia pestis, is a zoonotic infection that has caused three devastating global pandemics. While historically known for the "Black Death," the pathogen remains a contemporary public health concern, persisting in endemic foci across Asia, the Americas, and Africa. In Ecuador, the disease has evolved from a coastal epidemic into a complex Andean endemic since its introduction in 1908.
Methods: This study reviews the epidemiological trajectory of plague in Ecuador, which spans five distinct phases. Transmission dynamics were facilitated by maritime trade at the Port of Guayaquil and the national railway network, which served as a mechanical vector for infected rodents and fleas (Xenopsylla cheopis, Polygenis litragus) into the Inter-Andean heartland.
Results: The disease heavily impacted provinces such as Chimborazo, Tungurahua, and Loja. While coastal incidence declined by 1930, persistent foci remained in the highlands, sustained by favorable ecology and socioeconomic factors. Despite the establishment of the National Anti-Plague Service in 1960, a significant re-emergence occurred in 1998 in Galte Laime (Chimborazo), potentially triggered by climatic shifts from the 1996 El Niño phenomenon.
Conclusion: Plague management in Ecuador has transitioned toward rigorous epidemiological surveillance. Current strategies emphasize the active monitoring of rodent and flea reservoirs to prevent the fatal transition from bubonic to pneumonic plague. Continued vigilance remains essential in endemic zones to mitigate the risks posed by environmental and infrastructure-driven transmission.