The COVID-19 pandemic had a profound global impact, characterized by a high fatality rate and the emergence of enduring consequences known as Long COVID. Our study sought to gauge the prevalence of Long COVID syndrome in northeastern Mexico, correlating it with patients' comorbidities and vaccination records. We carried out an observational cross-sectional approach, by administering a comprehensive questionnaire covering patients' medical history, demographics, vaccination status, COVID-related symptoms, their duration, and any treatment received. Our participant cohort included 804 patients, averaging 41.5 (SD 13.6) years in age, with 59.3% being women. Notably, 168 individuals (20.9%) met Long COVID criteria. Our analysis of COVID-19 long lasting compared vaccination schemes, unveiling a significant difference between vaccinated and unvaccinated groups (p = <
0.001). Through linear regression model, we found male gender (β = - 0.588, p <
0.001) and vaccination status (β = 0.221, p = 0.015) acted as protective factors against Long COVID symptom duration, while higher BMI was a risk factor (β = - 0.131, p = 0.026). We saw that the duration of Long COVID was different within vaccinated patients, and we did not find any association of comorbidities with an increase in the presence of symptoms. Even three years after the pandemic, a significant prevalence of Long COVID persists, and there is still a lack of standardized information and any possible treatment regarding this condition.