Predictors of severe symptomatic laboratory-confirmed SARS-COV-2 reinfection

Murillo-Zamora, Efren; Mendoza-Cano, Oliver; Delgado-Enciso, Ivan; HERNANDEZ-SUAREZ, CARLOS M

BackgroundThere is a major concern regarding the prognosis of coronavirus disease 2019 (COVID-19) in patients who recovered to first-time illness. ObjectiveTo evaluate factors predicting severe symptomatic laboratory-confirmed (reverse transcription-quantitative polymerase chain reaction, RT-qPCR) SARS-COV-2 (severe acute coronavirus-2) reinfection. MethodWe conducted a nationwide retrospective cohort study in Mexico and data from 258 reinfection cases (at least 28 days between both episodes onset) were analyzed. We used risk ratios (RR) and 95% confidence intervals (CI) to evaluate predictors of severe (dyspnea requiring hospital admission) secondary SARS-COV-2 infection. ResultsThe risk of severe disease was 14.7% and the observed overall fatality rate was 4.3%. Patients with more serious primary disease were more likely to develop severe symptoms (39.5% vs. 5.5%, p < 0.001) during reinfection. In multiple analysis, factors associated with an increased risk of severe symptomatic SARS-COV-2 reinfection were increasing age (RR per year = 1.007, 95% CI 1.003-1.010), comorbidities (namely obesity [RR = 1.12, 95% CI 1.01-1.24], asthma [RR = 1.26, 95% CI 1.06-1.50], type 2 diabetes mellitus [RR = 1.22, 95% CI 1.07 - 1.38] and previous severe laboratory-confirmed COVID-19 (RR = 1.20, 95% CI 1.03-1.39). ConclusionsTo the best of our knowledge this is the first study evaluating disease outcomes in a large set of laboratory-positive cases of symptomatic SARS-COV-2 reinfection and factors associated with illness severity was characterized. Our results may contribute to the current knowledge of SARS-COV-2 pathogenicity and to identify populations at increased risk of a poorer outcome after reinfection.