RESUMO
Several vaccines have been developed to control the COVID-19 pandemic. CoronaVac®, an inactivated SARS-CoV-2 vaccine, has demonstrated safety and immunogenicity, preventing severe COVID-19 cases. We investigate the safety and non-inferiority of two immunization schedules of CoronaVac® in a non-inferiority trial in healthy adults. A total of 2302 healthy adults were enrolled at 8 centers in Chile and randomly assigned to two vaccination schedules, receiving two doses with either 14 or 28 days between each. The primary safety and efficacy endpoints were solicited adverse events (AEs) within 7 days of each dose, and comparing the number of cases of SARS-CoV-2 infection 14 days after the second dose between the schedules, respectively. The most frequent local AE was pain at the injection site, which was less frequent in participants aged ≥60 years. Other local AEs were reported in less than 5% of participants. The most frequent systemic AEs were headache, fatigue, and myalgia. Most AEs were mild and transient. There were no significant differences for local and systemic AEs between schedules. A total of 58 COVID-19 cases were confirmed, and all but 2 of them were mild. No differences were observed in the proportion of COVID-19 cases between schedules. CoronaVac® is safe, especially in ≥60-year-old participants. Both schedules protected against COVID-19 hospitalization.
RESUMO
INTRODUCCIÓN: La introducción progresiva de vacunas contra SARS-CoV-2 a partir de 2021, priorizando grupos de mayor edad, podría implicar un cambio en el perfil de pacientes hospitalizados por COVID-19 en el tiempo. OBJETIVO: Comparar las características y evolución de pacientes adultos hospitalizados por COVID-19 en un período anterior en 2020 (PER1) y otro posterior al inicio de la vacunación masiva contra SARS-CoV-2 (PER2). PACIENTES Y MÉTODOS: Se registró edad, género, comorbilidades, complicaciones y evolución de los pacientes hospitalizados por COVID-19 en una clínica privada, en Santiago, Chile. Se calculó el puntaje de gravedad y riesgo nutricional. RESULTADOS: En PER2, los pacientes fueron de menor edad, pero con comorbilidades similares al PER1, excepto por mayor malnutrición por exceso. Los pacientes del PER2 no vacunados requirieron más ventilación mecánica (38,9 vs. 14,3%, p = 0,03) y evolucionaron más gravemente (puntaje 6) que aquellos adecuadamente inmunizados (puntaje 5, p = 0,048). Las variables que más predijeron mortalidad fueron edad > 60 años (OR 28.995) y presencia de riesgo nutricional (OR 5.246). DISCUSIÓN: El cambio en el perfil y evolución de los pacientes hospitalizados con COVID-19 está asociado con la secuencia de priorización de vacunas contra SARS-CoV-2, cuyo efecto redujo las hospitalizaciones y gravedad de COVID-19 en adultos mayores.
BACKGROUND: During the COVID-19 pandemic, the early prioritization of SARS-CoV-2 vaccines for older adults may have affected the characteristics of hospitalized COVID-19 patients over time. AIM: To compare the clinical characteristics and outcomes of adult patients admitted for COVID-19 before (PER1) and after (PER2) the initiation of mass vaccination for SARS-CoV-2. METHODS: Data on age, gender, comorbidities, complications, and outcomes of adult patients hospitalized for COVID-19 in a private clinic of Santiago, Chile, were collected. Scores for COVID-19 severity and nutritional risk were calculated. RESULTS: In PER2, patients were younger but had similar comorbidities, except for a higher prevalence of overweight and obesity compared to PER1. Unvaccinated COVID-19 patients in PER2 required more invasive ventilatory support (38.9% vs. 14.3%, p = 0.03) and had a higher severity score (six) than vaccinated patients (five, p = 0.048). The variables that best predicted mortality were age > 60 years (OR 28,995) and the presence of nutritional risk (OR 5,246). DISCUSSION: Changes in the profile and outcomes of hospitalized patients during the COVID-19 pandemic are associated with the prioritization of SARS-CoV-2 vaccines and their protective effect in reducing hospitalizations and disease severity in older adults.