Evaluation of persistent COVID and SARS-CoV-2 reinfection in a cohort of patients on the island of Gran Canaria, Spain

INTRODUCTION: This study analyzed the impact of patients’ age, sex, vaccination, immunosuppressive treatment, and previous comorbidities on the risk of developing persistent COVID-19 or SARS-CoV-2 virus reinfection. METHOD: Population-based observational retrospective study of a cohort of 110,726 patients aged 12 years or older, who were diagnosed with COVID-19 between June 1st, 2021 and February 28th, 2022 in the island of Gran Canaria. RESULTS: 340 patients suffered reinfection. The combination of advanced age, female sex and lack of complete or incomplete vaccination against COVID-19 was strongly predictive of reinfection (p < 0.05). In the 188 patients who developed persistent COVID-19, the persistence of symptoms was more frequent in adult patients, women, and patients with a diagnosis of asthma. Complete vaccination was associated with a lower risk of reinfection ([OR] 0.05, 95%CI 0.04–0.07; p < 0.05) and of developing persistent COVID-19 ([OR] 0.07, 95%CI 0.05–0.10; p < 0.05). None of the patients with reinfection or persistent COVID-19 died during the period of the study. CONCLUSIONS: This study confirmed the link between age, sex, asthma and risk of persistent COVID-19. It was not possible to define the patient's comorbidities as a factor that influences the development of reinfection, but its association with age, sex, type of vaccine and hypertension was demonstrated. Higher vaccination coverage was associated with a lower risk of persistent COVID-19 or SARS-CoV-2 reinfection.