Zoonotic Alphaviruses in Costa Rica: Long-Term IgM Serosurveillance in Horses from 2009–2019

Title (eng)
Zoonotic Alphaviruses in Costa Rica: Long-Term IgM Serosurveillance in Horses from 2009–2019
Author
Bernal León
Author
Ana I. Ruiz
Author
Mario Baldi
Author
Annemarie Käsbohrer
Author
Clair L. Firth
Author
Carlos Jiménez
Author
Mafalda Viana
Author
Sabine E. Hutter
Abstract (eng)
Objective: This study aimed to determine the annually circulation of Venezuelan (VEEV), Eastern (EEEV), and Western (WEEV) equine encephalitis viruses, identify patterns in case occurrence, and assess the associations with environmental and geographic factors. Methods: Serum samples from 548 ill equines exhibiting fever, depression, and/or neurologic symptoms were analyzed over 11 years (2009–2019) using IgM MAC ELISA. Logistic models were used to determine the associations between VEEV seropositivity and environmental conditions. Results: VEEV was detected annually in 23.4% (128/548) of the cases, while EEEV appeared intermittently (1.5% [8/548]). No WEEV cases were detected, likely due to avian migratory flyway routes. VEEV exhibited a 6-year peak pattern linked to La Niña in Guanacaste province. Eleven human alphavirus cases were confirmed between 2013 and 2019, including 1 fatal VEEV case in a child. Conclusion: These findings underscore the need for continued equine alphavirus surveillance within the One Health framework.
Keywords (eng)
Venezuelan Equine EncephalitisEastern Equine EncephalitisVector-Borne DiseasesAlphavirusOne HealthSurveillanceZoonotic Pathogens
Type (eng)
journal article
Language
[eng]
Persistent identifier
https://phaidra.vetmeduni.ac.at/o:4763
DOI
10.15212/ZOONOSES-2024-0062
Is in series
Title (eng)
Zoonoses
Volume
5
Issue
1
ISSN
2737-7466
Issued
2025
Number of pages
14
Publication
ScienceOpen
Version type (eng)
version of record (published version)
Date issued
2025
Access rights (eng)
open access
License
CC BY 4.0 International
Rights statement (eng)
© 2025 The Authors