Objective: The objective of this study was to investigate the prevalence and carry out epidemiology using sociodemographic data from patients with symptoms suggestive of COVID-19 (SARS-CoV-2) in three bordering Brazilian municipalities. Methods: An epidemiological survey of positive cases of COVID-19 through RT-PCR was carried out in 1874 patients, seen in the Unified Health System (SUS), aged between 0-99 years, who had symptoms suggestive of COVID-19, from the cities of Assis Chateaubriand, Tupãssi, and Formosa do Oeste. Results: It was possible to observe that of the 1874 patients seen in the public health network of the three municipalities, 354 were diagnosed as positive. The predominance of cases was in female patients (51.97%) and in patients who lived in urban areas (93.50%), and the predominant age group was 20-29 years (19.78%). Conclusion: The result of this study demonstrated the epidemiological profile of patients with respiratory and flu-like symptoms, positive for COVID-19, in three municipalities bordering Paraguay and Argentina. It was evident that the age group has its specificities regarding the susceptibility of the infection. Although the borders are closed, there was probably a spread of the virus in this region, due to the diversion, which showed an increase during the pandemic period.