COVID-19 reinfections.

Reports of SARS-CoV-2 reinfections are on the rise. This study focused on reinfections in patients with confirmed COVID-19 in the Czech Republic. Between 1 March 2020 and 9 November 2020, 362 084 cases with the onset of symptoms before 31 October 2020 were reported. Overall, 28 cases of symptomatic SARS-CoV-2 reinfections were identified, 11 in males and 17 in females, age range 25-80 years, median age 46 years. The interval between the first and second episodes of the disease ranged from 101 to 231 days, and the median interval was 201.5 days. During both symptomatic episodes, all patients have been tested by RT-PCR. Altogether 26 patients (92.9%) have been tested negative after recovery from the first episode of COVID-19. Symptomatic reinfections occurred in nearly 0.2% of all patients at risk. Most patients with reinfection had mild symptoms in both episodes, and only three episodes were moderate to severe. Thus, reinfections may have been underdiagnosed. In summary, COVID-19 reinfections are possible and not exceptional.