Since December 2019, COVID-19, caused by the novel coronavirus (SARS-CoV-2), triggered a severe global health crisis, with particular prominence of severe acute respiratory syndrome cases. In Brazil, the state of Amazonas stood out as one of the first epicenters of the pandemic. On January 14, 2021, the public health network in Manaus collapsed due to excessive demand, resulting in hundreds of deaths caused by shortages of hospital oxygen. This study aimed to evaluate the clinical and epidemiological characteristics of hospitalized SARS/COVID-19 cases, comparing periods with and without vaccine availability. A cross-sectional epidemiological study was conducted using secondary data from patients hospitalized between April 2020 and April 2022 in Tabatinga, Amazonas, divided into a pre-vaccination period (April 2020 to March 2021) and a vaccination period (April 2021 to April 2022), with a diagnosis of severe acute respiratory syndrome due to COVID-19. There were 538 COVID-19 hospitalizations during the period; 307 (57.1%) were male patients. In the pre-vaccination period, 32.1% of cases required care in an Intensive Care Unit (ICU) and orotracheal intubation (OTI), while in the vaccination period this proportion was 5% (PR 6.5; 95% CI 3.6–11.8). Mortality was 36.7% in the first period, compared with 9.5% once immunization was available (PR 3.9; 95% CI 2.5–6.0). After vaccine introduction, there was a change in the age profile of hospitalized patients, from 58 years (median) to 8 years in the vaccination period (p < 0.001). The data show that during the vaccination period there was a decline in lethality, the need for ICU admission, and the total number of hospitalizations. These findings reinforce the need to strengthen primary prevention policies, emphasizing the importance of COVID-19 vaccination campaigns.
Moreira et al. (Sun,) studied this question.