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de Jesus Á, Ernesto R, Massinga AJ, Nhacolo F, Munguambe K, Timana A, Nhacolo A, Messa A, Massora S, Escola V, Enosse S, Gunjamo R, Funzamo C, Mwenda JM, Okeibunor J, Garcia-Basteiro A, Guinovart C, Mayor A, Mandomando I. High SARS-CoV-2 Exposure in Rural Southern Mozambique After Four Waves of COVID-19: Community-Based Seroepidemiological Surveys. Influenza Other Respir Viruses 2024; 18:e13332. [PMID: 38838093 DOI: 10.1111/irv.13332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 03/08/2024] [Accepted: 05/19/2024] [Indexed: 06/07/2024] Open
Abstract
BACKGROUND Mozambique was one of many African countries with limited testing capacity for SARS-CoV-2. Serosurveys, an alternative to estimate the real exposure to understand the epidemiology and transmission dynamics, have been scarce in Mozambique. Herein, we aimed to estimate the age-specific seroprevalence of SARS-CoV-2 in the general population of the Manhiça District, at four time points, for evaluating dynamics of exposure and the impact of vaccination. METHODS We conducted four community-based seroepidemiological surveys separated by 3 months between May 2021 and June 2022 to assess the prevalence of SARS-CoV-2 antibodies. An age-stratified (0-19, 20-39, 40-59, and ≥ 60 years) sample of 4810 individuals was randomly selected from demographic surveillance database, and their blood samples were analyzed using WANTAI SARS-CoV-2 IgG + IgM ELISA. Nasopharyngeal swabs from a subsample of 2209 participants were also assessed for active infection by RT-qPCR. RESULTS SARS-CoV-2 seroprevalence increased from 27.6% in the first survey (May 2021) to 63.6%, 91.2%, and 91.1% in the second (October 2021), third (January 2022), and fourth (May 2022) surveys, respectively. Seroprevalence in individuals < 18 years, who were not eligible for vaccination, increased from 23.1% in the first survey to 87.1% in the fourth. The prevalence of active infection was below 10.1% in all surveys. CONCLUSIONS A high seroprevalence to SARS-CoV-2 was observed in the study population, including individuals not eligible for vaccination at that time, particularly after circulation of the highly transmissible Delta variant. These data are important to inform decision making on the vaccination strategies in the context of pandemic slowdown in Mozambique.
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Affiliation(s)
- Áuria de Jesus
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Rita Ernesto
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | | | - Felizarda Nhacolo
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Khátia Munguambe
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- Faculdade de Medicina, Universidade Eduardo Mondlane (UEM), Maputo, Mozambique
| | - Alcido Timana
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Arsénio Nhacolo
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Augusto Messa
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Sérgio Massora
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Valdemiro Escola
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Sónia Enosse
- Instituto Nacional de Saúde (INS), Ministério da Saúde, Marracuene-Maputo, Mozambique
| | - Rufino Gunjamo
- Instituto Nacional de Saúde (INS), Ministério da Saúde, Marracuene-Maputo, Mozambique
| | - Carlos Funzamo
- Mozambique Country Office, World Health Organization, Maputo, Mozambique
| | - Jason M Mwenda
- Regional Office for Africa (AFRO), World Health Organization, Brazzaville, Republic of Congo
| | - Joseph Okeibunor
- Regional Office for Africa (AFRO), World Health Organization, Brazzaville, Republic of Congo
| | - Alberto Garcia-Basteiro
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
- Amsterdam Institute for Global Health and Development, Academic Medical Centre, Amsterdam, The Netherlands
| | | | - Alfredo Mayor
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
- Department of Physiologic Sciences, Faculty of Medicine, Universidade Eduardo Mondlane, Maputo, Mozambique
| | - Inácio Mandomando
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- Instituto Nacional de Saúde (INS), Ministério da Saúde, Marracuene-Maputo, Mozambique
- ISGlobal, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain
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Seabra SG, Merca F, Pereira B, Fonseca I, Carvalho AC, Brito V, Alves D, Libin P, Martins MRO, Miranda MNS, Pingarilho M, Pimentel V, Abecasis AB. Serological screening in a large-scale municipal survey in Cascais, Portugal, during the first waves of the COVID-19 pandemic: lessons for future pandemic preparedness efforts. Front Public Health 2024; 12:1326125. [PMID: 38371240 PMCID: PMC10869482 DOI: 10.3389/fpubh.2024.1326125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 01/11/2024] [Indexed: 02/20/2024] Open
Abstract
Background Serological surveys for SARS-CoV-2 were used early in the COVID-19 pandemic to assess epidemiological scenarios. In the municipality of Cascais (Portugal), serological testing combined with a comprehensive socio-demographic, clinical and behavioral questionnaire was offered to residents between May 2020 and beginning of 2021. In this study, we analyze the factors associated with adherence to this municipal initiative, as well as the sociodemographic profile and chronic diseases clinical correlates associated to seropositivity. We aim to contribute with relevant information for future pandemic preparedness efforts. Methods This was a cross-sectional study with non-probabilistic sampling. Citizens residing in Cascais Municipality went voluntarily to blood collection centers to participate in the serological survey. The proportion of participants, stratified by socio-demographic variables, was compared to the census proportions to identify the groups with lower levels of adherence to the survey. Univariate and multivariate logistic regression were used to identify socio-demographic, clinical and behavioral factors associated with seropositivity. Results From May 2020 to February 2021, 19,608 participants (9.2% of the residents of Cascais) were included in the study. Based on the comparison to census data, groups with lower adherence to this survey were men, the youngest and the oldest age groups, individuals with lower levels of education and unemployed/inactive. Significant predictors of a reactive (positive) serological test were younger age, being employed or a student, and living in larger households. Individuals with chronic diseases generally showed lower seroprevalence. Conclusion The groups with low adherence to this voluntary study, as well as the socio-economic contexts identified as more at risk of viral transmission, may be targeted in future pandemic situations. We also found that the individuals with chronic diseases, perceiving higher risk of serious illness, adopted protective behaviors that limited infection rates, revealing that health education on preventive measures was effective for these patients.
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Affiliation(s)
- Sofia G. Seabra
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, Lisbon, Portugal
| | - Francisco Merca
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, Lisbon, Portugal
- Artificial Intelligence Research Lab, Vrije Universiteit Brussels (VUB), Pleinlaan 2, Brussel, Belgium
| | - Bernardo Pereira
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, Lisbon, Portugal
| | - Ivo Fonseca
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, Lisbon, Portugal
| | | | - Vera Brito
- Câmara Municipal de Cascais, Cascais, Portugal
| | - Daniela Alves
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, Lisbon, Portugal
| | - Pieter Libin
- Artificial Intelligence Research Lab, Vrije Universiteit Brussels (VUB), Pleinlaan 2, Brussel, Belgium
- Interuniversity Institute of Biostatistics and Statistical Bioinformatics, Data Science Institute, Hasselt University, Hasselt, Belgium
| | - M. Rosário O. Martins
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, Lisbon, Portugal
| | - Mafalda N. S. Miranda
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, Lisbon, Portugal
| | - Marta Pingarilho
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, Lisbon, Portugal
| | - Victor Pimentel
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, Lisbon, Portugal
| | - Ana B. Abecasis
- Global Health and Tropical Medicine, GHTM, Associate Laboratory in Translation and Innovation Towards Global Health, LA-REAL, Instituto de Higiene e Medicina Tropical, IHMT, Universidade NOVA de Lisboa, UNL, Rua da Junqueira 100, Lisbon, Portugal
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Owusu-Boaitey N, Russell TW, Meyerowitz-Katz G, Levin AT, Herrera-Esposito D. Dynamics of SARS-CoV-2 seroassay sensitivity: a systematic review and modelling study. Euro Surveill 2023; 28:2200809. [PMID: 37227301 PMCID: PMC10283460 DOI: 10.2807/1560-7917.es.2023.28.21.2200809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 03/10/2023] [Indexed: 05/26/2023] Open
Abstract
BackgroundSerological surveys have been the gold standard to estimate numbers of SARS-CoV-2 infections, the dynamics of the epidemic, and disease severity. Serological assays have decaying sensitivity with time that can bias their results, but there is a lack of guidelines to account for this phenomenon for SARS-CoV-2.AimOur goal was to assess the sensitivity decay of seroassays for detecting SARS-CoV-2 infections, the dependence of this decay on assay characteristics, and to provide a simple method to correct for this phenomenon.MethodsWe performed a systematic review and meta-analysis of SARS-CoV-2 serology studies. We included studies testing previously diagnosed, unvaccinated individuals, and excluded studies of cohorts highly unrepresentative of the general population (e.g. hospitalised patients).ResultsOf the 488 screened studies, 76 studies reporting on 50 different seroassays were included in the analysis. Sensitivity decay depended strongly on the antigen and the analytic technique used by the assay, with average sensitivities ranging between 26% and 98% at 6 months after infection, depending on assay characteristics. We found that a third of the included assays departed considerably from manufacturer specifications after 6 months.ConclusionsSeroassay sensitivity decay depends on assay characteristics, and for some types of assays, it can make manufacturer specifications highly unreliable. We provide a tool to correct for this phenomenon and to assess the risk of decay for a given assay. Our analysis can guide the design and interpretation of serosurveys for SARS-CoV-2 and other pathogens and quantify systematic biases in the existing serology literature.
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Affiliation(s)
- Nana Owusu-Boaitey
- Case Western Reserve University School of Medicine, Cleveland, United States
- These authors contributed equally to this work
| | - Timothy W Russell
- Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | - Andrew T Levin
- Dartmouth College, Hanover, United States
- National Bureau for Economic Research, Cambridge, United States
- Centre for Economic Policy Research, London, United Kingdom
| | - Daniel Herrera-Esposito
- These authors contributed equally to this work
- Department of Psychology, University of Pennsylvania, Philadelphia, United States
- Laboratorio de Neurociencias, Universidad de la República, Montevideo, Uruguay
- Centro Interdisciplinario en Ciencia de Datos y Aprendizaje Automático, Universidad de la República, Montevideo, Uruguay
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Axfors C, Pezzullo AM, Contopoulos-Ioannidis DG, Apostolatos A, Ioannidis JPA. Differential COVID-19 infection rates in children, adults, and elderly: Systematic review and meta-analysis of 38 pre-vaccination national seroprevalence studies. J Glob Health 2023; 13:06004. [PMID: 36655924 PMCID: PMC9850866 DOI: 10.7189/jogh.13.06004] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Background Debate exists about whether extra protection of elderly and other vulnerable individuals is feasible in COVID-19. We aimed to assess the relative infection rates in the elderly vs the non-elderly and, secondarily, in children vs adults. Methods We performed a systematic review and meta-analysis of seroprevalence studies conducted in the pre-vaccination era. We identified representative national studies without high risk of bias through SeroTracker and PubMed searches (last updated May 17, 2022). We noted seroprevalence estimates for children, non-elderly adults, and elderly adults, using cut-offs of 20 and 60 years (or as close to these ages, if they were unavailable) and compared them between different age groups. Results We included 38 national seroprevalence studies from 36 different countries comprising 826 963 participants. Twenty-six of these studies also included pediatric populations and twenty-five were from high-income countries. The median ratio of seroprevalence in elderly vs non-elderly adults (or non-elderly in general, if pediatric and adult population data were not offered separately) was 0.90-0.95 in different analyses, with large variability across studies. In five studies (all in high-income countries), we observed significant protection of the elderly with a ratio of <0.40, with a median of 0.83 in high-income countries and 1.02 elsewhere. The median ratio of seroprevalence in children vs adults was 0.89 and only one study showed a significant ratio of <0.40. The main limitation of our study is the inaccuracies and biases in seroprevalence studies. Conclusions Precision shielding of elderly community-dwelling populations before the availability of vaccines was indicated in some high-income countries, but most countries failed to achieve any substantial focused protection. Registration Open Science Framework (available at: https://osf.io/xvupr).
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Affiliation(s)
- Cathrine Axfors
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, California, USA,Department for Women’s and Children’s Health, Uppsala University, Uppsala, Sweden
| | - Angelo Maria Pezzullo
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, California, USA,Section of Hygiene, Department of Life Sciences and Public Health, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Despina G Contopoulos-Ioannidis
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, California, USA,Division of Infectious Diseases, Department of Pediatrics, Stanford University School of Medicine, Stanford, California, USA
| | - Alexandre Apostolatos
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, California, USA,Faculty of Medicine, Université de Montréal, Montreal, Canada
| | - John PA Ioannidis
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, California, USA,Departments of Medicine, of Epidemiology and Population Health, of Biomedical Data Science, and of Statistics, Stanford University, Stanford, California, USA
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Pezzullo AM, Axfors C, Contopoulos-Ioannidis DG, Apostolatos A, Ioannidis JPA. Age-stratified infection fatality rate of COVID-19 in the non-elderly population. ENVIRONMENTAL RESEARCH 2023; 216:114655. [PMID: 36341800 PMCID: PMC9613797 DOI: 10.1016/j.envres.2022.114655] [Citation(s) in RCA: 25] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 10/21/2022] [Accepted: 10/22/2022] [Indexed: 05/02/2023]
Abstract
The largest burden of COVID-19 is carried by the elderly, and persons living in nursing homes are particularly vulnerable. However, 94% of the global population is younger than 70 years and 86% is younger than 60 years. The objective of this study was to accurately estimate the infection fatality rate (IFR) of COVID-19 among non-elderly people in the absence of vaccination or prior infection. In systematic searches in SeroTracker and PubMed (protocol: https://osf.io/xvupr), we identified 40 eligible national seroprevalence studies covering 38 countries with pre-vaccination seroprevalence data. For 29 countries (24 high-income, 5 others), publicly available age-stratified COVID-19 death data and age-stratified seroprevalence information were available and were included in the primary analysis. The IFRs had a median of 0.034% (interquartile range (IQR) 0.013-0.056%) for the 0-59 years old population, and 0.095% (IQR 0.036-0.119%) for the 0-69 years old. The median IFR was 0.0003% at 0-19 years, 0.002% at 20-29 years, 0.011% at 30-39 years, 0.035% at 40-49 years, 0.123% at 50-59 years, and 0.506% at 60-69 years. IFR increases approximately 4 times every 10 years. Including data from another 9 countries with imputed age distribution of COVID-19 deaths yielded median IFR of 0.025-0.032% for 0-59 years and 0.063-0.082% for 0-69 years. Meta-regression analyses also suggested global IFR of 0.03% and 0.07%, respectively in these age groups. The current analysis suggests a much lower pre-vaccination IFR in non-elderly populations than previously suggested. Large differences did exist between countries and may reflect differences in comorbidities and other factors. These estimates provide a baseline from which to fathom further IFR declines with the widespread use of vaccination, prior infections, and evolution of new variants.
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Affiliation(s)
- Angelo Maria Pezzullo
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, CA, USA; Sezione di Igiene, Dipartimento di Scienze della Vita e Sanità Pubblica, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Cathrine Axfors
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, CA, USA
| | - Despina G Contopoulos-Ioannidis
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, CA, USA; Division of Infectious Diseases, Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, USA
| | - Alexandre Apostolatos
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, CA, USA; Faculty of Medicine, Université de Montréal, Montreal, Canada
| | - John P A Ioannidis
- Meta-Research Innovation Center at Stanford (METRICS), Stanford University, Stanford, CA, USA; Departments of Medicine, of Epidemiology and Population Health, of Biomedical Data Science, and of Statistics, Stanford University, Stanford, CA, USA.
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Ait Bennacer S, Aaroud A, Sabiri K, Rguibi MA, Cherradi B. Design and implementation of a New Blockchain-based digital health passport: A Moroccan case study. INFORMATICS IN MEDICINE UNLOCKED 2022; 35:101125. [PMID: 36345287 PMCID: PMC9630302 DOI: 10.1016/j.imu.2022.101125] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 10/31/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022] Open
Abstract
In the context of COVID-19 pandemic, the Moroccan Interior and Health Ministries have proposed to use the health pass with a QR code to identify vaccinated people. Additionally, the government suggested a mobile application to control the health passport authenticity. However, the key problem is the possibility of anyone scanning the QR code and figuring out citizens' private information, causing severe issues about individual privacy. In this work, the main contribution is integrating a private Blockchain-based digital health passport to ensure high protection of sensitive information, security and privacy among all the actors (Government, Ministry of Interior, Ministry of Health, verifiers) that comply with the CNDP (National Commission for the Control of Personal Data Protection) and the Moroccan Law 09–08. In our proposed architectural framework solution, we identify two types of actors: authorized and unauthorized, to limit and control access to the citizens' personal information. Besides, to preserve individuals' privacy, we adopt on-chain and off-chain storage (Interplanetary File Systems IPFS). In our case, smart contracts improve security and privacy in the health passport verification process. Our system implementation describes the proposed solution to grant individual privacy. To verify and validate our approach, we used Remix-IDE and Ethereum Blockchain to build smart contracts.
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Pluss O, Campbell H, Pezzi L, Morales I, Roell Y, Quandelacy TM, Arora RK, Boucher E, Lamb MM, Chu M, Bärnighausen T, Jaenisch T. Limitations introduced by a low participation rate of SARS-CoV-2 seroprevalence data. Int J Epidemiol 2022; 52:32-43. [PMID: 36164817 PMCID: PMC9619459 DOI: 10.1093/ije/dyac178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 08/31/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND There has been a large influx of COVID-19 seroprevalence studies, but comparability between the seroprevalence estimates has been an issue because of heterogeneities in testing platforms and study methodology. One potential source of heterogeneity is the response or participation rate. METHODS We conducted a review of participation rates (PR) in SARS-CoV-2 seroprevalence studies collected by SeroTracker and examined their effect on the validity of study conclusions. PR was calculated as the count of participants for whom the investigators had collected a valid sample, divided by the number of people invited to participate in the study. A multivariable beta generalized linear model with logit link was fitted to determine if the PR of international household and community-based seroprevalence studies was associated with the factors of interest, from 1 December 2019 to 10 March 2021. RESULTS We identified 90 papers based on screening and were able to calculate the PR for 35 out of 90 papers (39%), with a median PR of 70% and an interquartile range of 40.92; 61% of the studies did not report PR. CONCLUSIONS Many SARS-CoV-2 seroprevalence studies do not report PR. It is unclear what the median PR rate would be had a larger portion not had limitations in reporting. Low participation rates indicate limited representativeness of results. Non-probabilistic sampling frames were associated with higher participation rates but may be less representative. Standardized definitions of participation rate and data reporting necessary for the PR calculations are essential for understanding the representativeness of seroprevalence estimates in the population of interest.
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Affiliation(s)
- Olivia Pluss
- Center for Global Health, Colorado School of Public Health, University of Colorado, Aurora, CO, USA
| | - Harlan Campbell
- Department of Statistics, University of British Columbia, Vancouver, Canada
| | - Laura Pezzi
- Unité des Virus Émergents (UVE: Aix-Marseille Univ-IRD 190-Inserm 1207), Marseille, France
| | - Ivonne Morales
- Division of Infectious Disease and Tropical Medicine, Center for Infectious Diseases, Heidelberg University Hospital, Heidelberg, Germany,Heidelberg Institute for Global Health, Heidelberg University Hospital, Heidelberg, Germany
| | - Yannik Roell
- Center for Global Health, Colorado School of Public Health, University of Colorado, Aurora, CO, USA
| | - Talia M Quandelacy
- Department of Epidemiology, Colorado School of Public Health, University of Colorado, Aurora, CO, USA
| | - Rahul Krishan Arora
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK,Department of Community Health Sciences, University of Calgary, Calgary, AB, Canada
| | - Emily Boucher
- Cumming School of Medicine, University of Calgary, Calgary, AB, Canada,Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Molly M Lamb
- Center for Global Health, Colorado School of Public Health, University of Colorado, Aurora, CO, USA,Department of Epidemiology, Colorado School of Public Health, University of Colorado, Aurora, CO, USA
| | - May Chu
- Center for Global Health, Colorado School of Public Health, University of Colorado, Aurora, CO, USA
| | - Till Bärnighausen
- Heidelberg Institute for Global Health, Heidelberg University Hospital, Heidelberg, Germany
| | - Thomas Jaenisch
- Corresponding author. Department of Epidemiology and Center for Global Health, Colorado School of Public Health, 13199 East Montview Boulevard, Suite 310, Mail Stop A090, Aurora, CO 80045, USA. E-mail:
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Sheikh Ali S, Kheirallah KA, Sharkas G, Al-Nusair M, Al-Mistarehi AH, Ghazo M, Zeitawi A, Bellizzi S, Ramadan M, Alsulaiman JW, Alzoubi H, Belbesi A, Allouh MZ. SARS-CoV-2 Seroepidemiological Investigation in Jordan: Seroprevalence, Herd Immunity, and Vaccination Coverage. A Population-Based National Study. Int J Gen Med 2022; 15:7053-7062. [PMID: 36090704 PMCID: PMC9462546 DOI: 10.2147/ijgm.s371711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 07/01/2022] [Indexed: 12/02/2022] Open
Abstract
Background Population-based serosurveillance is a cornerstone to furthering our understanding of the COVID-19 pandemic at the community levels. In Jordan, four waves (phases) of seroprevalence epidemiological investigations were conducted using representative population-based national samples. This study aims to estimate the population-based seropositivity, herd immunity, and vaccination coverage at the fourth wave. Methods Multistage sampling technique was implemented to recruit a nationally representative sample for the fourth wave of the seroprevalence investigation (June to August 2021). Electronically collected data utilized a questionnaire on background demographics, chronic diseases, and COVID-19 vaccination history. Also, blood samples were collected to detect the presence of total Anti-SARS-CoV-2 IgM and IgG using Wantai/ELISA assays. Prevalence estimates were presented using percentage and 95% Confidence Intervals (C.I.). Results There were 8821 participants included in this study, with a mean age of 31.3 years, and 61.7% were females. COVID-19 national seroprevalence and vaccination coverage estimates were 74.1% (95% C.I.: 73.1–74.9%) and 38.4% (95% C.I.: 37.1–39.6%), respectively. Among children, seroprevalence estimates were similar to unvaccinated adults. Among COVID-19 adults, 57.2% were vaccinated. Among vaccinated participants, 91.5% were seropositive, while among unvaccinated, 63.2% were seropositive. By age group, seroprevalence ranged between 53.0% and 86.9%. Seroprevalence estimates were significantly different by gender, vaccination status and dose, and residence. Conclusion The reported interplay between seropositivity and vaccination coverage estimate seems insufficient to provide herd immunity levels to combat new variants of SARS-CoV-2. Children and healthcare workers seem to be an epidemiologically influential group in spreading COVID-19. As the globe is still grappling with SARS-CoV-2 infection, national seroepidemiological evidence from Jordan calls for more focus on vaccination coverage, especially among epidemiologically vulnerable groups, to optimize herd immunity.
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Affiliation(s)
- Sami Sheikh Ali
- Epidemics Management, Jordan Ministry of Health, Amman, Jordan
| | - Khalid A Kheirallah
- Department of Public Health and Community Medicine, Faculty of Medicine, Jordan University of Science and Technology, Irbid, Jordan
- Correspondence: Khalid A Kheirallah, Department of Public Health and Community Medicine, Faculty of Medicine, Jordan University of Science and Technology, P. O. Box: 3030, Irbid, 22110, Jordan, Tel +962 7 9611 9094, Email
| | - Ghazi Sharkas
- Epidemics Management, Jordan Ministry of Health, Amman, Jordan
| | - Mohammed Al-Nusair
- Department of Public Health and Community Medicine, Faculty of Medicine, Jordan University of Science and Technology, Irbid, Jordan
| | - Abdel-Hameed Al-Mistarehi
- Department of Public Health and Community Medicine, Faculty of Medicine, Jordan University of Science and Technology, Irbid, Jordan
| | - Mahmoud Ghazo
- Epidemics Management, Jordan Ministry of Health, Amman, Jordan
| | - Ali Zeitawi
- Epidemics Management, Jordan Ministry of Health, Amman, Jordan
| | - Saverio Bellizzi
- Emergency Program, World Health Organization, Jordan Country Office, Amman, Jordan
| | - Mohannad Ramadan
- Emergency Program, World Health Organization, Jordan Country Office, Amman, Jordan
| | - Jomana W Alsulaiman
- Department of Pediatrics, Faculty of Medicine, Yarmouk University, Irbid, Jordan
| | - Hamed Alzoubi
- Department of Microbiology and Immunology, Faculty of Medicine, Mutah University, Mutah, Jordan
| | - Adel Belbesi
- Epidemics Management, Jordan Ministry of Health, Amman, Jordan
| | - Mohammed Z Allouh
- Department of Anatomy, Faculty of Medicine, Jordan University of Science and Technology, Irbid, Jordan
- Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
- Mohammed Z Allouh, Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, P. O. Box: 15551, Al Ain, United Arab Emirates, Tel +971 3 713 7551, Email
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9
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Kittel M, Eichner R, Aida S, Bode A, Ast V, Kessler A, Neumaier M, Wölfel R, Haselmann V. Results of a European-Wide External Quality Assessment (EQA) Scheme for Serological Detection of Anti-SARS-CoV-2 (CoVimm)—Pitfalls of Routine Application. Viruses 2022; 14:v14081662. [PMID: 36016287 PMCID: PMC9412523 DOI: 10.3390/v14081662] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 07/15/2022] [Accepted: 07/19/2022] [Indexed: 12/05/2022] Open
Abstract
Background: During the last two years, a variety of assays for the serological detection of antibodies to the new SARS-CoV-2 virus have been launched and used as part of standard care in many laboratories. The pace with which these tests have been introduced into routine care emphasizes the importance of quality measures for analytical methods, particularly with regard to the implications of results for clinical and epidemiologic decisions. Accuracy, reliability and comparability of analytical test results are thus essential, and here external quality assessment (EQA) is the most important quality assurance tool. It allows us to achieve harmonization of test methods as a prerequisite for a high standard of performance for laboratory and analytical techniques and their interpretation. Methods: This EQA scheme consisted of pre-characterized clinical biospecimens dedicated to the analysis of anti-SARS-CoV-2 IgG total antibodies and differentiation into spike protein-specific IgG antibodies against SARS-CoV-2 (anti-S-SARS-CoV-2) and nucleocapsid-specific IgG antibodies against SARS-CoV-2 (anti-N-SARS-CoV-2). Results: A total of 239 laboratories across Europe participated in this scheme, called CoVimm. In detail, 536 results for anti-SARS-CoV-2 IgG, 431 results for anti-S-SARS-CoV-2 IgG, and 200 results for anti-N-SARS-CoV-2 IgG were reported. Based on the pre-defined thresholds, the success rates for the determination of anti-S-SARS-CoV-2 IgG and anti-N-SARS-CoV-2 IgG were 96% and 90%, respectively. Interestingly, only 64% of the participating laboratories successfully passed the EQA scheme for the determination of total anti-SARS-CoV-2 IgG. Conclusions: This EQA revealed serious concerns regarding the reliability and appropriate use of anti-SARS-CoV-2 antibody assays in routine care. In addition to the wide heterogeneity of different assays used by participating laboratories, a lack of standardization and harmonization is also evident. This is of particular importance for reliable and clinically meaningful interpretation of test results.
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Affiliation(s)
- Maximilian Kittel
- Department of Clinical Chemistry, University Medical Centre Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany; (M.K.); (R.E.); (S.A.); (V.A.); (M.N.)
| | - Romy Eichner
- Department of Clinical Chemistry, University Medical Centre Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany; (M.K.); (R.E.); (S.A.); (V.A.); (M.N.)
| | - Sihem Aida
- Department of Clinical Chemistry, University Medical Centre Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany; (M.K.); (R.E.); (S.A.); (V.A.); (M.N.)
| | - Anna Bode
- Reference Institute for Bioanalytics, Stiftung für Pathobiochemie und Molekulare Diagnostik, 53175 Bonn, Germany; (A.B.); (A.K.)
| | - Volker Ast
- Department of Clinical Chemistry, University Medical Centre Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany; (M.K.); (R.E.); (S.A.); (V.A.); (M.N.)
| | - Anja Kessler
- Reference Institute for Bioanalytics, Stiftung für Pathobiochemie und Molekulare Diagnostik, 53175 Bonn, Germany; (A.B.); (A.K.)
| | - Michael Neumaier
- Department of Clinical Chemistry, University Medical Centre Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany; (M.K.); (R.E.); (S.A.); (V.A.); (M.N.)
| | - Roman Wölfel
- Bundeswehr Institute of Microbiology, 80937 Munich, Germany;
- German Center for Infection Research (DZIF), Partner Site Munich, 80333 Munich, Germany
| | - Verena Haselmann
- Department of Clinical Chemistry, University Medical Centre Mannheim, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany; (M.K.); (R.E.); (S.A.); (V.A.); (M.N.)
- Correspondence:
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10
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Royo-Cebrecos C, Robert-Montaner Ï, Vilanova D, Bailles E, Serrano-Pons J, Valero O, Buldon JM, Bermudez-de-Castro L, Mahia E, Pujadas J, Cobo F, Piqué JM, Albiol S. Seroprevalence study prior and post vaccination in cancer patients in principality of Andorra (COVONCO study). J Cancer Res Clin Oncol 2022:10.1007/s00432-022-04141-8. [PMID: 35809113 PMCID: PMC10064610 DOI: 10.1007/s00432-022-04141-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 06/13/2022] [Indexed: 10/17/2022]
Abstract
BACKGROUND COVID-19 serologic response in patients with cancer may be lower than in the general population and may be influenced by the type of tumor or anticancer treatment. This study aims to analyze serological response prior and after vaccination of COVID-19 within the oncological population in Andorra. We set out to identify risk factors for a higher or lower serological response. PATIENTS AND METHODS Observational, unicentric, prospective cohort study of oncologic patients in Andorra. We calculated the seroprevalence of antibodies against SARS-CoV-2 (May 2020-June 2021) and analyzed the main demographic, oncologic features and factors associated with being seropositive. RESULTS A total of 373 patients were analyzed, mainly with solid tumours (n = 334, 89.5%). At baseline, seroprevalence was 13%, increasing during follow-up to 19%; lower seroprevalence was observed in patients with hematologic malignancies (2.6% vs 14.2%; p = 0.041) and patients receiving biological therapies (0% vs 15%, p = 0.005). In the overall seroprevalence analysis, women (23% vs 11.9%; p = 0.006) and tumour-free patients (p = 0.034) showed higher seroprevalence. The multivariable analysis showed that odds of being seropositive were higher among women (OR: 2.44, 95% CI 1.28-4.64), and patients who underwent surgery (OR: 3.35, 95% CI 1.10-10.20). About 80% of the cohort received at least one dose of COVID-19 vaccination, showing a higher seroprevalence of patients who received ChAdOx1-S than those who received BNT162b2 (24.4% vs 6.4%: p = 0.001). CONCLUSION The seroprevalence of antibodies against SARS-COV-2 in oncologic patients in Andorra was higher among females and patients who received hormonal therapy and surgery while patients with hematologic malignancies and biologic therapies showed lower seropositivity without finding differences in the type of tumour or anticancer treatment.
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Affiliation(s)
- Cristina Royo-Cebrecos
- Department of Internal Medicine, Hospital Nostra Senyora de Meritxell, Andorra Andorra Health Services (SAAS), Av. Fiter i Rosell 1-13, AD700, Escaldes-Engordany, Andorra.
| | - Ïa Robert-Montaner
- University of Nottingham Medical School, Queens Medical Centre, Nottingham, UK
| | | | - Eva Bailles
- Psychology Department, Hospital Nostra Senyora de Meritxell, SAAS, Escaldes-Engordany, Andorra
| | - Jordi Serrano-Pons
- Founder of UniversalDoctor: The Digital Global Health Company, Barcelona, Spain
| | - Oliver Valero
- Servei d'Estadística Aplicada, Universitat Autònoma de Barcelona. Cerdanyola del Vallès, Barcelona, Spain
| | - Josep Maria Buldon
- Biostatistics, Hospital Nostra Senyora de Meritxell, SAAS, Escaldes-Engordany, Andorra
| | | | - Eva Mahia
- Oncology Department of Hospital Nostra Senyora de Meritxell, SAAS, Escaldes-Engordany, Andorra
| | - Jaume Pujadas
- Oncology Department of Hospital Nostra Senyora de Meritxell, SAAS, Escaldes-Engordany, Andorra
| | - Francesc Cobo
- Hematology Department of Hospital Nostra Senyora de Meritxell, SAAS, Escaldes-Engordany, Andorra
| | | | - Santiago Albiol
- Oncology Department of Hospital Nostra Senyora de Meritxell, SAAS, Escaldes-Engordany, Andorra
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11
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Berke A, Doorley R, Alonso L, Arroyo V, Pons M, Larson K. Using mobile phone data to estimate dynamic population changes and improve the understanding of a pandemic: A case study in Andorra. PLoS One 2022; 17:e0264860. [PMID: 35472092 PMCID: PMC9041757 DOI: 10.1371/journal.pone.0264860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 02/17/2022] [Indexed: 11/29/2022] Open
Abstract
Compartmental models are often used to understand and predict the progression of an infectious disease such as COVID-19. The most basic of these models consider the total population of a region to be closed. Many incorporate human mobility into their transmission dynamics, usually based on static and aggregated data. However, mobility can change dramatically during a global pandemic as seen with COVID-19, making static data unsuitable. Recently, large mobility datasets derived from mobile devices have been used, along with COVID-19 infections data, to better understand the relationship between mobility and COVID-19. However, studies to date have relied on data that represent only a fraction of their target populations, and the data from mobile devices have been used for measuring mobility within the study region, without considering changes to the population as people enter and leave the region. This work presents a unique case study in Andorra, with comprehensive datasets that include telecoms data covering 100% of mobile subscribers in the country, and results from a serology testing program that more than 90% of the population voluntarily participated in. We use the telecoms data to both measure mobility within the country and to provide a real-time census of people entering, leaving and remaining in the country. We develop multiple SEIR (compartmental) models parameterized on these metrics and show how dynamic population metrics can improve the models. We find that total daily trips did not have predictive value in the SEIR models while country entrances did. As a secondary contribution of this work, we show how Andorra’s serology testing program was likely impacted by people leaving the country. Overall, this case study suggests how using mobile phone data to measure dynamic population changes could improve studies that rely on more commonly used mobility metrics and the overall understanding of a pandemic.
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Affiliation(s)
- Alex Berke
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA, United States of America
- * E-mail:
| | - Ronan Doorley
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA, United States of America
| | - Luis Alonso
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA, United States of America
| | | | - Marc Pons
- Andorra Recerca + Innovació, Andorra
| | - Kent Larson
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA, United States of America
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12
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Dayanand D, Irudhayanathan I, Kundu D, Manesh A, Abraham V, Abhilash KP, Chacko B, Moorthy M, Samuel P, Peerawaranun P, Mukaka M, Joseph J, Sivaprakasam M, Varghese GM. Community seroprevalence and risk factors for SARS CoV-2 infection in different subpopulations in Vellore, India and its implications for future prevention. Int J Infect Dis 2021; 116:138-146. [PMID: 34971822 PMCID: PMC8712712 DOI: 10.1016/j.ijid.2021.12.356] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/22/2021] [Accepted: 12/22/2021] [Indexed: 11/30/2022] Open
Abstract
Objectives The aim of this study was to inform public health policy decisions through the assessment of IgG antibody seroprevalence in the population and the risk factors for SARS-CoV-2 infection. Methods The seroprevalence of IgG antibodies among different subpopulations at the end of the first and second waves of the pandemic was estimated. Various risk factors associated with seropositivity, including sociodemography, IgG antibodies against endemic human coronavirus, and vaccination status, were also assessed. Results For all 2433 consenting participants, the overall estimated seroprevalences at the end of first and second waves were 28.5% (95% CI 22.3–33.7%) and 71.5% (95% CI 62.8–80.5%), respectively. The accrual of IgG positivity was heterogeneous, with the highest seroprevalences found in urban slum populations (75.1%). Vaccine uptake varied among the subpopulations, with low rates (< 10%) among rural and urban slum residents. The majority of seropositive individuals (75%) were asymptomatic. Residence in urban slums (OR 2.02, 95% CI 1.57–2.6; p < 0.001), middle socioeconomic status (OR 1.77, 95% CI 1.17–2.67; p = 0.007), presence of diabetes (OR 1.721, 95% CI 1.148–2.581; p = 0.009), and hypertension (OR 1.75, 95% CI 1.16–2.64; p = 0.008) were associated with seropositivity in multivariable analyses. Conclusion Although considerable population immunity has been reached, with more than two-thirds seropositive, improved vaccination strategies among unreached subpopulations and high-risk individuals are suggested for better preparedness in future.
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Affiliation(s)
- Divya Dayanand
- Department of Infectious Diseases, Christian Medical College, Vellore, Tamil Nadu, India
| | - Indhuja Irudhayanathan
- Department of Infectious Diseases, Christian Medical College, Vellore, Tamil Nadu, India
| | - Debasree Kundu
- Department of Infectious Diseases, Christian Medical College, Vellore, Tamil Nadu, India
| | - Abi Manesh
- Department of Infectious Diseases, Christian Medical College, Vellore, Tamil Nadu, India
| | - Vinod Abraham
- Department of Community Health, Christian Medical College, Vellore, Tamil Nadu, India
| | | | - Binila Chacko
- Department of Critical Care Medicine, Christian Medical College, Vellore, Tamil Nadu, India
| | - Mahesh Moorthy
- Department of Clinical Virology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Prasanna Samuel
- Department of Biostatistics, Christian Medical College, Vellore, Tamil Nadu, India
| | - Pimnara Peerawaranun
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Mavuto Mukaka
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, University of Oxford, UK
| | - Jayaraj Joseph
- Department of Electrical Engineering, Indian Institute of TechnologyMadras, Tamil Nadu, India; Healthcare Technology Innovation Centre (HTIC), Indian Institute of Technology Madras, Tamil Nadu, India
| | - Mohanasankar Sivaprakasam
- Department of Electrical Engineering, Indian Institute of TechnologyMadras, Tamil Nadu, India; Healthcare Technology Innovation Centre (HTIC), Indian Institute of Technology Madras, Tamil Nadu, India
| | - George M Varghese
- Department of Infectious Diseases, Christian Medical College, Vellore, Tamil Nadu, India.
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13
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Doorley R, Berke A, Noyman A, Alonso L, Ribo J, Arroyo V, Pons M, Larson K. Mobility and COVID-19 in Andorra: Country-scale analysis of high-resolution mobility patterns and infection spread. IEEE J Biomed Health Inform 2021; 26:183-193. [PMID: 34665749 DOI: 10.1109/jbhi.2021.3121165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Throughout the COVID-19 pandemic, non- pharmaceutical interventions, such as mobility restrictions, have been globally adopted as critically important strategies to curb the spread of infection. However, such interventions come with immense social and economic costs and the relative effectiveness of different mobility restrictions are not well understood. Some recent works have used telecoms data sources that cover fractions of a population to understand behavioral changes and how these changes have impacted case growth. This study analyzed uniquely comprehensive datasets in order to examine the relationship between mobility and transmission of COVID- 19 in the country of Andorra. The data consisted of spatio-temporal telecoms data for all mobile subscribers in the country, serology screening results for 91% of the population, and COVID-19 case reports. A comprehensive set of mobility metrics was developed using the telecoms data to indicate entrances to the country, contact with tourists, stay-at-home rates, trip-making and levels of crowding. Mobility metrics were compared to infection rates across communities and transmission rate over time. All metrics dropped sharply at the start of the countrys lockdown and gradually rose again as the restrictions were gradually lifted. Several of these metrics were highly correlated with lagged transmission rate. There was a stronger correlation for measures of indoor crowding and inter-community trip-making, and a weaker correlation for total trips (including intra-community trips) and stay-at- homes rates. These findings provide support for policies which aim to discourage gathering indoors while lifting the most restrictive mobility limitations.
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