The sudden pandemic caused by SARS-CoV-2 exposed healthcare professionals worldwide to high viral loads, in an early epidemiological moment, often without the recommended personal protective equipment. We report the case of a Brazilian doctor who, after presenting a mild clinical episode of COVID-19 with molecular confirmation by RT-PCR in March 2020, appeared with a new acute infection by SARS-CoV-2 three months later. In middle of June, she had significant and very specific symptoms of COVID-19 with tomographic and serological confirmation of reinfection. There is a strong probability that these two episodes of infection were caused by different viral strains and that each genetic variation is related to specific clinical manifestations. We observed that, in addition to the different symptoms presented in the reinfections' episode, there was a more intense organic inflammatory response to the virus, with clinical repercussion. This clinical case should be an alert regarding the maintenance of individual protection among health cares, even in individuals who have already had COVID-19, since there is still no guarantee of prolonged immunity. This article is protected by copyright. All rights reserved.