Loading...
6 results
Search Results
Now showing 1 - 6 of 6
- Mathematical Modelling of the Impact of Non-Pharmacological Strategies to Control the COVID-19 Epidemic in PortugalPublication . Caetano, Constantino; Morgado, Maria Luísa; Patrício, Paula; Pereira, João E.; Nunes, BaltazarIn this paper, we present an age-structured SEIR model that uses contact patterns to reflect the physical distance measures implemented in Portugal to control the COVID-19 pandemic. By using these matrices and proper estimates for the parameters in the model, we were able to ascertain the impact of mitigation strategies employed in the past. Results show that the March 2020 lockdown had an impact on disease transmission, bringing the effective reproduction number (R(t)) below 1. We estimate that there was an increase in the transmission after the initial lift of the measures on 6 May 2020 that resulted in a second wave that was curbed by the October and November measures. December 2020 saw an increase in the transmission reaching an R(t) = 1.45 in early January 2021. Simulations indicate that the lockdown imposed on the 15 January 2021 might reduce the intensive care unit (ICU) demand to below 200 cases in early April if it lasts at least 2 months. As it stands, the model was capable of projecting the number of individuals in each infection phase for each age group and moment in time.
- Pregnancy during COVID-19: social contact patterns and vaccine coverage of pregnant women from CoMix in 19 European countriesPublication . Wong, Kerry L.M.; Gimma, Amy; Paixao, Enny; Paolotti, Daniela; Karch, André; Jäger, Veronika; Baruch, Joaquin; Melillo, Tanya; Hudeckova, Henrieta; Rosińska-Bukowska, Magdalena; Niedźwiedzka-Stadnik, Marta; Fischer, Krista; Vorobjov, Sigrid; Sõnajalg, Hanna; Althaus, Christian; Low, Nicola; Reichmuth, Martina L.; Auranen, Kari; Nurhonen, Markku; Petrović, Goranka; Makaric, Zvjezdana Lovric; Namorado, Sónia; Caetano, Constantino; Santos, Ana João; Röst, Gergely; Oroszi, Beatrix; Karsai, Márton; Fafangel, Mario; Klepac, Petra; Kranjec, Natalija; Vilaplana, Cristina; Casabona-Barbarà, Jordi; FAES, Christel; Beutels, Philippe; Hens, Niel; Jarvis, Christopher; Edmunds, JohnBackground: Evidence and advice for pregnant women evolved during the COVID-19 pandemic. We studied social contact behaviour and vaccine uptake in pregnant women between March 2020 and September 2021 in 19 European countries. Methods: In each country, repeated online survey data were collected from a panel of nationally-representative participants. We calculated the adjusted mean number of contacts reported with an individual-level generalized additive mixed model, modelled using the negative binomial distribution and a log link function. Mean proportion of people in isolation or quarantine, and vaccination coverage by pregnancy status and gender were calculated using a clustered bootstrap. Findings: We recorded 4,129 observations from 1,041 pregnant women, and 115,359 observations from 29,860 non-pregnant individuals aged 18-49. Pregnant women made slightly fewer contacts (3.6, 95%CI = 3.5-3.7) than non-pregnant women (4.0, 95%CI = 3.9-4.0), driven by fewer work contacts but marginally more contacts in non-essential social settings. Approximately 15-20% pregnant and 5% of non-pregnant individuals reported to be in isolation and quarantine for large parts of the study period. COVID-19 vaccine coverage was higher in pregnant women than in non-pregnant women between January and April 2021. Since May 2021, vaccination in non-pregnant women began to increase and surpassed that in pregnant women. Interpretation: Limited social contact to avoid pathogen exposure during the COVID-19 pandemic has been a challenge to many, especially women going through pregnancy. More recognition of maternal social support desire is needed in the ongoing pandemic. As COVID-19 vaccination continues to remain an important pillar of outbreak response, strategies to promote correct information can provide reassurance and facilitate informed pregnancy vaccine decisions in this vulnerable group.
- Métodos epidemiológicos e estatísticos numa emergência de Saúde PúblicaPublication . Nunes, Baltazar; Caetano, Constantino; Antunes, Liliana; Torres, Ana Rita; Silva, Susana; Rodrigues, Ana Paula; Kislaya, Irina; Machado, Ausenda; Garcia, Ana Cristina; Gómez, Verónica; Namorado, Sónia; Patrício, Paula; Ribeiro, Maria Luísa; Pereira, João; Matias Dias, CarlosSobre o papel dos método estatístico e epidemiológico na resposta à emergência COVID-19: Vigilância epidemiológica; Estudos epidemiológicos especiais; Modelação matemática.
- Statistics in Times of Pandemics: the Role of Statistical and Epidemiological Methods during the COVID-19 Emergency. One Day Meeting on Statistics and Applied ProbabilityPublication . Nunes, Baltazar; Caetano, Constantino; Antunes, Liliana; Torres, Ana Rita; Silva, Susana; Rodrigues, Ana Paula; Kislaya, Irina; Machado, Ausenda; Garcia, Ana Cristina; Gómez, Verónica; Namorado, Sónia; Patrício, Paula; Ribeiro, Maria Luísa; Pereira, João; Matias Dias, CarlosAbout the Role of Statistical and Epidemiological Methods during the COVID-19 Emergency.
- Social contact patterns during the COVID-19 pandemic in 21 European countries - evidence from a two-year studyPublication . Wong, Kerry L.M.; Gimma, Amy; Coletti, Pietro; Paolotti, Daniela; Tizzani, Michele; Cattuto, Ciro; Schmidt, Andrea; Gredinger, Gerald; Stumpfl, Sophie; Baruch, Joaquin; Melillo, Tanya; Hudeckova, Henrieta; Zibolenova, Jana; Chladna, Zuzana; Rosinska, Magdalena; Niedzwiedzka-Stadnik, Marta; Fischer, Krista; Vorobjov, Sigrid; Sõnajalg, Hanna; Althaus, Christian; Low, Nicola; Reichmuth, Martina; Auranen, Kari; Nurhonen, Markku; Petrović, Goranka; Makaric, Zvjezdana Lovric; Namorado, Sónia; Caetano, Constantino; Santos, Ana João; Röst, Gergely; Oroszi, Beatrix; Karsai, Márton; Fafangel, Mario; Klepac, Petra; Kranjec, Natalija; Vilaplana, Cristina; Casabona, Jordi; Faes, Christel; Beutels, Philippe; Hens, Niel; Jaeger, Veronika K.; Karch, Andre; Johnson, Helen; Jarvis, Christopher I.Background: Most countries have enacted some restrictions to reduce social contacts to slow down disease transmission during the COVID-19 pandemic. For nearly two years, individuals likely also adopted new behaviours to avoid pathogen exposure based on personal circumstances. We aimed to understand the way in which different factors affect social contacts - a critical step to improving future pandemic responses. Methods: The analysis was based on repeated cross-sectional contact survey data collected in a standardized international study from 21 European countries between March 2020 and March 2022. We calculated the mean daily contacts reported using a clustered bootstrap by country and by settings (at home, at work, or in other settings). Where data were available, contact rates during the study period were compared with rates recorded prior to the pandemic. We fitted censored individual-level generalized additive mixed models to examine the effects of various factors on the number of social contacts. Results: The survey recorded 463,336 observations from 96,456 participants. In all countries where comparison data were available, contact rates over the previous two years were substantially lower than those seen prior to the pandemic (approximately from over 10 to < 5), predominantly due to fewer contacts outside the home. Government restrictions imposed immediate effect on contacts, and these effects lingered after the restrictions were lifted. Across countries, the relationships between national policy, individual perceptions, or personal circumstances determining contacts varied. Conclusions: Our study, coordinated at the regional level, provides important insights into the understanding of the factors associated with social contacts to support future infectious disease outbreak responses.
- Relative vaccine effectiveness against COVID-19 hospitalisation in persons aged ≥ 65 years: results from a VEBIS network, Europe, October 2021 to July 2023Publication . Fontán-Vela, Mario; Kissling, Esther; Nicolay, Nathalie; Braeye, Toon; Van Evercooren, Izaak; Holm Hansen, Christian; Emborg, Hanne-Dorthe; Fabiani, Massimo; Mateo-Urdiales, Alberto; AlKerwi, Ala'a; Schmitz, Susanne; Castilla, Jesús; Martínez-Baz, Iván; de Gier, Brechje; Hahné, Susan; Meijerink, Hinta; Starrfelt, Jostein; Nunes, Baltazar; Caetano, Constantino; Derrough, Tarik; Nardone, Anthony; Monge, Susana; VEBIS-Lot 4 working groupSince 2021, the Vaccine Effectiveness, Burden and Impact Studies of coronavirus disease 2019 (COVID-19) and influenza (VEBIS) project monitors vaccine effectiveness (VE) in real-world conditions to inform vaccination programmes in the European Union/European Economic Area (EU/EEA) countries [1]. One project aims to monitor real-time COVID-19 VE using electronic health registries (EHR) in multiple countries, with initial findings previously published [2-4]. We report pooled VE results against hospitalisation due to COVID-19 by number of doses received and time since vaccination in a community-dwelling resident population aged ≥ 65 years between October 2021 and July 2023.