SARS-CoV-2 variant of concern P.1 (Gamma) infection in young and middle-aged patients admitted to the intensive care units of a single hospital in Salvador, northeast Brazil, February 2021

Nonaka, Carolina Kymie Vasques; Gräf, Tiago; Barcia, Camila Araújo de Lorenzo; Costa, Vanessa Ferreira; de Oliveira, Janderson Lopes; Passos, Rogério da Hora; Bastos, Iasmin Nogueira; de Santana, Maria Clara Brito; Santos, Ian Marinho; de Sousa, Karoline Almeida Felix; Weber, Thamires Gomes Lopes; de Siqueira, Isadora Cristina; Rocha, Clarissa Araújo Gurgel; Mendes, Ana Verena Almeida; Souza, Bruno Solano de Freitas

OBJECTIVES: To evaluate changes in COVID-19 patients' characteristics occurring after the emergence of the SARS-CoV-2 variant of concern (VOC) P.1 (Gamma) by comparing the clinical, demographic and laboratory profile of patients hospitalized during the first (May-July 2020) and second (December 2020 - February 2021) pandemic waves. METHODS: Data was collected from records of COVID-19 patients (n=4164) admitted to a single hospital in Salvador, Northeast Brazil. SARS-CoV-2 genome sequencing was performed in nasopharyngeal swab samples from 12 patients with age < 60 years-old admitted to the intensive care units (ICU) in February 2021. RESULTS: From June 2020 to February 2021, the median age of patients admitted in the ICU decreased from 66 to 58 years (p<0.05), accompanied by an increased proportion of patients without comorbidities (15.32% vs 32.20%, p<0.0001). A significant reduction in the Ct values of SARS-CoV-2 RT-PCR tests was observed in the second wave (p<0.0001). Sequencing analysis detected lineage Gamma in all 12 ICU patients sampled in February 2021. CONCLUSION: Our results demonstrated an increased proportion of younger adults without comorbidities with severe disease during the second COVID-19 wave, shortly after the confirmation of local Gamma circulation.