TWO-YEAR EPIDEMIOLOGICAL SURVEILLANCE OF EQUINE INFECTIOUS ANEMIA IN AN INSTITUTIONAL HORSE STABLES IN CHIAPAS, MEXICO

• DOI: https://doi.org/10.22533/at.ed.8135425100714

• Palavras-chave: Equine infectious anemia, cumulative incidence, epidemiological surveillance, horses.

• Keywords: Equine infectious anemia, cumulative incidence, epidemiological surveillance, horses.

• Abstract:

  Horses (Equus caballus L.) are highly important in the country's production systems, as they are used for work, transport, and support in agricultural activities, as well as occupying a prominent place in Mexico's social and cultural life. Horses are a symbol of national identity and tradition; the so-called cuacos are prized for their strength, docility, and endurance. 
  Their economic value is high, as they represent a significant investment for producers and breeders. Therefore, preserving their health and preventing diseases such as equine infectious anemia is essential to maintaining their productivity and the role they play in the rural economy and national culture. In short, comprehensive management focused on animal welfare is essential, regardless of the zootechnical purpose for which these highly prized animals are intended.
  Equine infectious anemia (EIA) is a viral disease that affects horses worldwide. This infection, initially known as swamp fever, is caused by a lentivirus belonging to the Retroviridae family, Orthoretrovirinae subfamily. The host's immune response manifests itself with the production of precipitating antibodies against the Equine Infectious Anemia Virus (EIAV), which can be detected by serological tests such as ELISA and Agar Gel Immunodiffusion (AGID) (WOAH/OIE, 2019).
  In Mexico, the disease was first diagnosed in 1999 in the state of Baja California. Subsequently, in 2003, an outbreak was reported in the same state, with an estimated economic loss of one million dollars. Some reports indicate that the prevalence of EIA in the country has been estimated at 1.45% in Federal Inspection Type (TIF) slaughterhouses, while in the North, Northwest, Gulf Coast, and Isthmus of Tehuantepec regions, the figures have varied between 0.3 and 13.8% (AMMVEE, 2024).
   Meanwhile, in a study conducted on working equines (horses and donkeys), Sánchez-Contreras et al. (2018) reported a prevalence of 37.7% in horses in the municipality of Veracruz, Veracruz, also using serological tests for the detection of EIA. These findings coincide with those of Ibarra et al. (2025), who showed a seroprevalence of 38.4% in Sonora, Mexico, as well as the records of Villa-Mancera et al. (2024), who published a seroprevalence of 15.25% in Puebla and 20.49% in Veracruz. 
  Taken together, the results of different studies show an upward trend in the detection of seropositive cases, suggesting the persistence and possible spread of the virus in different regions of the country. In this context, the objective of this study was to evaluate the incidence and epidemiological indicators of equine infectious anemia in the Llano San Juan de Ocozocoautla de Espinosa cavalry in Chiapas, in order to contribute to the knowledge of its behavior and the implementation of more effective health control strategies.