Browsing by Author "Leite, Pedro Pinto"
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- Comparative complete scheme and booster effectiveness of COVID‐19 vaccines in preventing SARS‐CoV‐2 infections with SARS‐CoV‐2 Omicron (BA.1) and Delta (B.1.617.2) variants: A case–case study based on electronic health recordsPublication . Kislaya, Irina; Peralta‐Santos, André; Borges, Vítor; Vieira, Luís; Sousa, Carlos; Ferreira, Bibiana; Pelerito, Ana; Gomes, João Paulo; Leite, Pedro Pinto; Nunes, Baltazar; on behalf of PT COVID-19 groupBackground: 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 RT-PCR SARS-CoV-2-positive cases notified in Portugal during Weeks 49-51, 2021. To obtain measure of comparative vaccine effectiveness, we compared the odds of vaccination in Omicron cases versus Delta using logistic regression adjusted for age group, sex, region, week of diagnosis, and laboratory of origin. Results: Higher odds of vaccination were observed in cases infected by Omicron VOC compared with Delta VOC cases for both complete primary vaccination (odds ratio [OR] = 2.1; 95% confidence interval [CI]: 1.8 to 2.4) and booster dose (OR = 5.2; 95% CI: 3.1 to 8.8), equivalent to reduction of vaccine effectiveness from 44.7% and 92.8%, observed against infection with Delta, to -6.0% (95% CI: 29.2% to 12.7%) and 62.7% (95% CI: 35.7% to 77.9%), observed against infection with Omicron, for complete primary vaccination and booster dose, respectively. Conclusion: Consistent reduction in vaccine-induced protection against infection with Omicron was observed. Complete primary vaccination may not be protective against SARS-CoV-2 infection in regions where Omicron variant is dominant.
- Comparative Effectiveness of COVID-19 Vaccines in Preventing Infections and Disease Progression from SARS-CoV-2 Omicron BA.5 and BA.2, PortugalPublication . Kislaya, Irina; Casaca, Pedro; Borges, Vítor; Sousa, Carlos; Ferreira, Bibiana I.; Fonte, Ana; Fernandes, Eugénia; Dias, Carlos Matias; Duarte, Sílvia; Almeida, José Pedro; Grenho, Inês; Coelho, Luís; Ferreira, Rita; Ferreira, Patrícia Pita; Borges, Cláudia Medeiros; Isidro, Joana; Pinto, Miguel; Menezes, Luís; Sobral, Daniel; Nunes, Alexandra; Santos, Daniela; Gonçalves, António Maia; Vieira, Luís; Gomes, João Paulo; Leite, Pedro Pinto; Nunes, Baltazar; Machado, Ausenda; Peralta-Santos, AndréWe 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 regression. For the cohort study, we estimated VE against disease progression using a penalized logistic regression. We observed no reduced VE for primary (aOR 1.07 [95% CI 0.93-1.23]) or booster (aOR 0.96 [95% CI 0.84-1.09]) vaccination against BA.5 infection. Among BA.5 case-patients, booster VE against progression to hospitalization was lower than that among BA.2 case-patients (VE 77% [95% CI 49%-90%] vs. VE 93% [95% CI 86%-97%]). Although booster vaccination is less effective against BA.5 than against BA.2, it offers substantial protection against progression from BA.5 infection to severe disease.
- Estimated number of lives directly saved by COVID-19 vaccination programmes in the WHO European Region from December, 2020, to March, 2023: a retrospective surveillance studyPublication . Meslé, Margaux M.I.; Brown, Jeremy; Mook, Piers; Katz, Mark A.; Hagan, José; Pastore, Roberta; Benka, Bernhard; Redlberger-Fritz, Monika; Bossuyt, Nathalie; Stouten, Veerle; Vernemmen, Catharina; Constantinou, Elisabet; Maly, Marek; Kynčl, Jan; Sanca, Ondrej; Krause, Tyra Grove; Vestergaard, Lasse Skafte; Leino, Tuija; Poukka, Eero; Gkolfinopoulou, Kassiani; Mellou, Kassiani; Tsintziloni, Maria; Molnár, Zsuzsanna; Aspelund, Gudrun; Thordardottir, Marianna; Domegan, Lisa; Kelly, Eva; O'Donell, Joan; Urdiales, Alberto-Mateo; Riccardo, Flavia; Sacco, Chiara; Bumšteinas, Viktoras; Liausediene, Rasa; Mossong, Joël; Vergison, Anne; Borg, Maria-Louise; Melillo, Tanya; Kocinski, Dragan; Pollozhani, Enkela; Meijerink, Hinta; Costa, Diana; Gomes, João Paulo; Leite, Pedro Pinto; Druc, Alina; Gutu, Veaceslav; Mita, Valentin; Lazar, Mihaela; Popescu, Rodica; Popovici, Odette; Musilová, Monika; Mrzel, Maja; Socan, Maja; Učakar, Veronika; Limia, Aurora; Mazagatos, Clara; Olmedo, Carmen; Dabrera, Gavin; Kall, Meaghan; Sinnathamby, Mary; McGowan, Graham; McMenamin, Jim; Morrison, Kirsty; Nitzan, Dorit; Widdowson, Marc-Alain; Smallwood, Catherine; Pebody, Richard; WHO European Respiratory Surveillance NetworkBackground: By March, 2023, 54 countries, areas, and territories (hereafter CAT) in the WHO European Region had reported more than 2·2 million COVID-19-related deaths to the WHO Regional Office for Europe. Here, we estimated how many lives were directly saved by vaccinating adults in the WHO European Region from December, 2020, to March, 2023. Methods: In this retrospective surveillance study, we estimated the number of lives directly saved by age group, vaccine dose, and circulating variant-of-concern (VOC) period, regionally and nationally, using weekly data on COVID-19 mortality and infection, COVID-19 vaccination uptake, and SARS-CoV-2 virus characterisations by lineage downloaded from The European Surveillance System on June 11, 2023, as well as vaccine effectiveness data from the literature. We included data for six age groups (25-49 years, 50-59 years, ≥60 years, 60-69 years, 70-79 years, and ≥80 years). To be included in the analysis, CAT needed to have reported both COVID-19 vaccination and mortality data for at least one of the four older age groups. Only CAT that reported weekly data for both COVID-19 vaccination and mortality by age group for 90% of study weeks or more in the full study period were included. We calculated the percentage reduction in the number of expected and reported deaths. Findings: Between December, 2020, and March, 2023, in 34 of 54 CAT included in the analysis, COVID-19 vaccines reduced deaths by 59% overall (CAT range 17-82%), representing approximately 1·6 million lives saved (range 1·5-1·7 million) in those aged 25 years or older: 96% of lives saved were aged 60 years or older and 52% were aged 80 years or older; first boosters saved 51% of lives, and 60% were saved during the Omicron period. Interpretation: Over nearly 2·5 years, most lives saved by COVID-19 vaccination were in older adults by first booster dose and during the Omicron period, reinforcing the importance of up-to-date vaccination among the most at-risk individuals. Further modelling work should evaluate indirect effects of vaccination and public health and social measures.