5 documents found, page 1 of 1
Comparative Effectiveness of COVID-19 Vaccines in Preventing Infections and Dis...
Kislaya, Irina; Casaca, Pedro; Borges, Vítor; Sousa, Carlos; Ferreira, Bibiana I.; Fonte, Ana; Fernandes, Eugénia; Dias, Carlos Matias; Duarte, SílviaWe estimated comparative primary and booster vaccine effectiveness (VE) of SARS-CoV-2 Omicron BA.5 and BA.2 lineages against infection and disease progression. During April-June 2022, we implemented a case-case and cohort study and classified lineages using whole-genome sequencing or spike gene target failure. For the case-case study, we estimated the adjusted odds ratios (aORs) of vaccination using a logistic ...
Stability of hybrid versus vaccine immunity against BA.5 infection over 8 months
Malato, João; Ribeiro, Ruy; Fernandes, Eugénia; Leite, Pedro Pinto; Casaca, Pedro; Antunes, Carlos; Fonseca, Valter R; Gomes, MC; Graca, LuisThe coverage of SARS-CoV-2 vaccination in large parts of the world, together with the high number of breakthrough infections, especially following the emergence of Omicron subvariants, makes hybrid immunity (resulting from vaccine and infection) common. Hybrid immunity, particularly after BA.1 or BA.2 infection, confers substantial protection against the BA.5 infection. However, although the waning of protectio...
Comparative complete scheme and booster effectiveness of COVID‐19 vaccines in p...
Kislaya, Irina; Peralta‐Santos, André; Borges, Vítor; Vieira, Luís; Sousa, Carlos; Ferreira, Bibiana; Pelerito, Ana; Gomes, João PauloBackground: Information on vaccine effectiveness in a context of novel variants of concern (VOC) emergence is of key importance to inform public health policies. This study aimed to estimate a measure of comparative vaccine effectiveness between Omicron (BA.1) and Delta (B.1.617.2 and sub-lineages) VOC according to vaccination exposure (primary or booster). Methods: We developed a case–case study using data on ...
Tracking SARS-CoV-2 lineage B.1.1.7 dissemination: insights from nationwide spi...
Borges, Vítor; Sousa, Carlos; Menezes, Luís; Gonçalves, António Maia; Picão, Miguel; Almeida, José Pedro; Vieita, Margarida; Santos, RafaelWe show that the SARS-CoV-2 B.1.1.7 lineage is highly disseminated in Portugal, with the odds of B.1.1.7 proportion increasing at an estimated 89% (95% confidence interval: 83-95%) per week until week 3 2021. RT-PCR spike gene target late detection (SGTL) can constitute a useful surrogate to track B.1.1.7 spread, besides the spike gene target failure (SGTF) proxy. SGTL/SGTF samples were associated with statisti...
Characteristics of SARS-CoV-2 variants of concern B.1.1.7, B.1.351 or P.1: data...
Funk, Tjede; Pharris, Anastasia; Spiteri, Gianfranco; Bundle, Nick; Melidou, Angeliki; Carr, Michael; Gonzalez, Gabriel; Garcia-Leon, AlejandroWe compared 19,207 cases of SARS-CoV-2 variant B.1.1.7/S gene target failure (SGTF), 436 B.1.351 and 352 P.1 to non-variant cases reported by seven European countries. COVID-19 cases with these variants had significantly higher adjusted odds ratios for hospitalisation (B.1.1.7/SGTF: 1.7, 95% confidence interval (CI): 1.0-2.9; B.1.351: 3.6, 95% CI: 2.1-6.2; P.1: 2.6, 95% CI: 1.4-4.8) and B.1.1.7/SGTF and P.1 cas...