Objective: The aim of this study was to evaluate the seropositivity of rapid immunoglobulin G (IgG) and immunoglobulin M tests in patients recovered from coronavirus disease 2019 (COVID‑19). Background: Rapid severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) antigen‑detection tests can give results in less than 30 min to detect SARS‑CoV‑2. Patients and methods: This case–control study was performed in Toluca, Mexico, from September to October, 2020. Rapid test was performed in patients older than 18 years who were diagnosed with COVID‑19. Quantitative data were presented as mean ± SD and qualitative in percentages. Pearson correlation was performed between the COVID‑19 clinical severity scale and the waist and BMI variables. Results: Twenty‑five patients were included (mean age, 45.24 years). Through the Pearson correlation, a positive relation was found between COVID‑19 clinical severity score and waist circumference (R2 = 0.161, P = 0.046844) and between the first and BMI (R2 = 0.157, P = 0.049918). The mean COVID‑19 clinical severity score of the patients was 23.12 ± 15.23. Sixty‑eight percent of positive results were obtained for the detection of IgG antibodies. In patients who exceed a score of 18 in clinical manifestations, all results for the detection of IgG antibodies against SARS‑COV‑2 were positive after several months. Conclusion: Patients with comorbidities had a higher predisposition to a more severe COVID‑19 disease, the highest intensity of signs and symptoms, the highest immunological response, and the highest probability of having antibodies against SARS‑COV‑2 over time.