Background: Eastern Equine encephalitis (EEEV) and Venezuelan equine encephalitis (VEEV) are vector-borne diseases of public health concern that are likely to reemerge or spread due to climate change. Methods: Between 2005 and July 2023, a retrospective cross-sectional descriptive observational study was conducted to analyze the cases of EEEV and VEEV in Colombia. Climatic variables of temperature, rainfall, and El Niño and La Niña phenomena were analyzed. The reports of encephalitis cases were obtained from the Minister of Agriculture. Descriptive statistics were performed, and a Pearson correlation coefficient was used. Findings: 169 cases of EEEV and 102 of VEEV in horses were found; the cases remained low between 2005-2015. In 2016, there was a strong epizootic of EEEV (n=57 cases) in the department of Casanare bordering Venezuela. That same year, there was a significant increase in VEEV cases (n=15 cases) in the department of Cesar on the border with Venezuela. Between 2017 and 2019, there was a decrease in both cases of encephalitis, but in 2020, another essential epizootic appeared, with a peak of 31 cases of EEEV in the department of Casanare. The climatic variables and the phenomena of La Niña and El Niño are not associated with the cases of VEEV and EEEV. Interpretation: The solid epizootic activity of the EEEV and VEEV viruses shows that both viruses can become human and animal public health problems. Based on the present work, neighboring countries must be alerted to the increased encephalitis cases.Funding: None.Declaration of Interest: The authors declare they have no conflict of interest.