ABSTRACT
COVID-19 vaccines have been essential for reducing the impact of the pandemic; nevertheless, population-based data under real-life conditions are needed to compare their effectiveness in various contexts. The objective of this study was to estimate the effectiveness of vaccines in preventing hospitalization and death from COVID-19 in Colombia under real-life conditions among people aged 18 years and older, according to sex, age, confirmed history of COVID-19 and vaccination series, including the effects of boosters. This investigation was an observational, retrospective, population-based study based on the Colombian cohort "Esperanza". A total of 14,213,409 individuals aged 18 years and older were analyzed, who were matched in a 1:1 ratio of vaccinated to unvaccinated. The study groups consisted of unvaccinated individuals, those with a complete series (CS) and individuals with a CS plus booster. The vaccinated individuals received either homologous or heterologous vaccinations with Ad26.COV2-S, BNT162b2, ChAdOx1 nCoV-19, CoronaVac and mRNA-1273 vaccines. Follow-up was conducted between February 2021 and June 2022. Cox proportional hazards models were used, adjusted for potential confounders, to estimate the effectiveness of different vaccination series. For adults aged 18 years and older, the overall effectiveness of the vaccines in preventing hospitalization was 82.7% (95% CI 82.1-83.2) for CS and 80.2% (95%CI 78.7-81.6) for CS + booster. The effectiveness in preventing death was 86.0% (95%CI 85.5-86.5) for CS and 83.1% (95%CI 81.5-84.5) for CS + booster. Effectiveness decreased with age. While all efficacies were high, CoronaVac offered significantly lower protection, although this improved with a booster. Continued mass vaccination is pivotal, especially in low- and middle-income countries. The study highlights both the real-world effectiveness of these vaccines and the challenges in understanding waning immunity and the influence of different VoC(Variants of Concern) on results.
ABSTRACT
BACKGROUND: Solid-organ transplant recipients (SOTRs) have a higher risk of coronavirus disease 2019 (COVID-19) complications and death and a less powerful and lasting response to vaccines and to natural infection. In Colombia, this population was prioritized in the National Vaccination Plan against COVID-19 and received vaccines from different platforms. The aim of this study was to estimate the effectiveness of the complete vaccination schedule and of the vaccine booster for COVID-19 administered to SOTRs in Colombia. METHODS: A nested-cohort was assembled within the population-based ESPERANZA cohort and included the subset of 16 y and older SOTRs (n = 6963); the follow-up period spanned March 11, 2021, to May 11, 2022. The vaccine effectiveness was estimated with Cox proportional-hazards models so that the overall effectiveness of the complete vaccination schedule, the vaccine booster, each used vaccine, and the homologous and heterologous schedules were estimated, adjusting by the main confounders. RESULTS: The overall effectiveness of being fully vaccinated was 73.7% (95% confidence interval [CI], 68.9%-77.0%) to prevent COVID-19 infection, 83.7% (95% CI, 78.7%-87.5%) to prevent hospitalization, and 92.1% (95% CI, 88.8%-94.4%) to prevent death due to COVID-19. Similarly, the effectiveness of the vaccine booster was 76.7% (95% CI, 70.6%-81.5%), 86.9% (95% CI, 79.4%-91.6%), and 94.5% (95% CI, 89.8%-97.1%) to prevent confirmed COVID-19 infection, hospitalization, and death due to COVID-19, respectively. In both cases, there were no statistically significant differences across age groups. CONCLUSIONS: Findings from this work show a high protection of vaccination against infection, hospitalization, and death due to COVID-19 in SOTRs, which increases with the vaccine booster.
Subject(s)
COVID-19 Vaccines , COVID-19 , Organ Transplantation , Humans , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Immunization Schedule , Organ Transplantation/adverse effects , Transplant RecipientsABSTRACT
Background: Although clinical trials showed that vaccines have high efficacy and safety, differences in study designs and populations do not allow for comparison between vaccines and age groups. The objective of this study was to evaluate the effectiveness of vaccines against COVID-19 in real-world conditions in adults aged 60 years and older in Colombia. Methods: In this retrospective, population-based, matched cohort study, we evaluated the effectiveness of vaccines against COVID-19-related hospitalisation and death in people aged 60 years and older. The full cohort consisted of every person who was eligible to receive a COVID-19 vaccine in Colombia (the ESPERANZA cohort). The exposed cohort consisted of older adults who were fully vaccinated with Ad26.COV2-S, BNT162b2, ChAdOx1 nCoV-19, or CoronaVac, and who did not have a history of confirmed SARS-CoV-2 infection. The unexposed cohort were people aged 60 years and older who had not received any dose of a COVID-19 vaccine during the study period. Participant follow-up was done between March 11, 2021, and Oct 26, 2021. Vaccine effectiveness was estimated as 1- hazard ratio from cause-specific proportional hazards models in the presence of competing risks. We estimated the overall effectiveness of being fully vaccinated, as well as effectiveness for each vaccine, adjusting by main potential confounders. The effectiveness of each vaccine was also assessed by age groups (ages 60-69 years, 70-79 years, and ≥80 years). Findings: 2 828 294 participants were assessed between March 11 and Oct 26, 2021. For all ages, the overall effectiveness across all assessed COVID-19 vaccines at preventing hospitalisation without subsequent death was 61·6% (95% CI 58·0-65·0, p<0·0001), 79·8% (78·5-81·1, p<0·0001) for preventing death after hospitalisation with COVID-19, and 72·8% (70·1-75·3, p<0·0001) for preventing death without previous COVID-19 hospitalisation. The effectiveness of all vaccines analysed at preventing death after hospitalisation for COVID-19 was 22·6% lower in adults who were aged 80 and older (68·4% [65·7-70·9], p<0·0001) compared with adults aged between 60 and 69 years (91·0% [89·0-92·6], p<0·0001). Interpretation: All vaccines analysed in this study were effective at preventing hospitalisation and death from COVID-19 in fully vaccinated older adults, which is a promising result for the national vaccination programme against COVID-19 in Colombia and in countries where these biologics have been applied. Efforts should be improved to increase coverage among older adults. In addition, given that we observed that the effectiveness of vaccines declined with increasing age, a booster dose is also justified, which should be prioritised for older adults. Funding: Colombian Ministry of Health and Social Protection.
Subject(s)
COVID-19 Vaccines , COVID-19 , Aged , Aged, 80 and over , BNT162 Vaccine , ChAdOx1 nCoV-19 , Cohort Studies , Colombia , Humans , Middle Aged , Retrospective Studies , SARS-CoV-2ABSTRACT
Resumen Introducción: Datos de varios países del mundo sugieren que los niños con COVID-19 podrían presentar síntomas diferentes y menos graves que los adultos. Sin embargo, los patrones epidemiológicos y clínicos en este grupo poblacional son poco claros. Métodos: El presente es un estudio observacional, con una caracterización inicial transversal-analítica, y con un componente longitudinal o de seguimiento a un grupo de menores con sospecha y/o diagnóstico confirmado de COVID-19, que presentaron desenlaces como mejoría, traslado a un nivel superior de atención o defunción por sintomatología respiratoria. Los niños recibieron atención médica en el Hospital General Regional con Medicina Familiar N.° 1 (HGR C/MF N.° 1), y se les realizó prueba de reacción en cadena de la polimerasa en tiempo real (RT-PCR). Resultados: Se estudiaron 98 niños como casos sospechosos para COVID-19, a quienes se les realizó RT-PCR. Del total, 24 resultaron positivos y 74 fueron negativos. La mediana de edad de los participantes fue 64,4 meses (0 a 203 meses), 55 menores eran de sexo masculino, 59 niños tuvieron manejo ambulatorio, y de estos, 14 presentaron resultado positivo. Entre los que requirieron manejo hospitalario (39), 10 niños dieron positivo para SARS-CoV-2, 84,7% alcanzaron mejoría y fueron dados de alta, 4 fueron trasladados a hospitales de nivel superior de atención. De los 98 niños en estudio, 11 fallecieron, 7 con resultado negativo y 4 con resultado positivo para SARS-CoV-2. Conclusiones: Los principales síntomas de la población pediátrica en este estudio fueron fiebre, tos y malestar general. De los niños que fallecieron, 4 presentaron resultado positivo para SARS-CoV-2, no obstante, estos presentaban otras comorbilidades.
Abstract Introduction: Data from several countries around the world suggest that children with COVID-19 may present different and less severe symptoms than adults. However, the epidemiological and clinical patterns in this population group have been unclear. Methods: This is an observational study, with an initial cross-analytical characterization, and with a longitudinal or follow-up component in a group of minors with suspected and or confirmed case of COVID-19, which have outcomes such as improvement, transfer to a higher level of care or death due to respiratory symptoms. The children received medical attention at the Regional General Hospital with Family Medicine No 1 (HGR C / MF No 1), and underwent a Real Time Polymerase Chain Reaction test (RT-PCR). Results: 98 children were studied as suspected cases for COVID-19, who underwent RT-PCR. Of the total 24 were positive and 74 were negatives. The median age was 64.4 months (0 to 203 months), 55 minors were male, 59 children had outpatient management, and of these, 14 had a positive result. Among those who required hospital management (39), 10 children were positive for SARS-CoV-2, 84.7% achieved improvement and were discharged, and four were transferred to a higher level of care hospital. Of the 98 children in the study, 11 died, seven had a negative result and four a positive result for SARS-CoV-2. Conclusions: The main symptoms of the pediatric population in this study were fever, cough and general discomfort. Four of those who died had a positive result for SARS-CoV-2, however, they had other comorbidities.
