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Cavalcanti-Dantas VDM, Fernandes B, Dantas PHLF, Uchoa GR, Mendes AF, Araújo Júnior WOD, Castellano LRC, Fernandes AIV, Goulart LR, Oliveira RADS, Assis PACD, Souza JRD, Morais CNLD. Differential epitope prediction across diverse circulating variants of SARS-COV-2 in Brazil. Comput Biol Chem 2024; 112:108139. [PMID: 38972100 DOI: 10.1016/j.compbiolchem.2024.108139] [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: 10/18/2023] [Revised: 06/09/2024] [Accepted: 06/22/2024] [Indexed: 07/09/2024]
Abstract
COVID-19, caused by the SARS-COV-2 virus, induces numerous immunological reactions linked to the severity of the clinical condition of those infected. The surface Spike protein (S protein) present in Sars-CoV-2 is responsible for the infection of host cells. This protein presents a high rate of mutations, which can increase virus transmissibility, infectivity, and immune evasion. Therefore, we propose to evaluate, using immunoinformatic techniques, the predicted epitopes for the S protein of seven variants of Sars-CoV-2. MHC class I and II epitopes were predicted and further assessed for their immunogenicity, interferon-gamma (IFN-γ) inducing capacity, and antigenicity. For B cells, linear and structural epitopes were predicted. For class I MHC epitopes, 40 epitopes were found for the clades of Wuhan, Clade 2, Clade 3, and 20AEU.1, Gamma, and Delta, in addition to 38 epitopes for Alpha and 44 for Omicron. For MHC II, there were differentially predicted epitopes for all variants and eight equally predicted epitopes. These were evaluated for differences in the MHC II alleles to which they would bind. Regarding B cell epitopes, 16 were found in the Wuhan variant, 14 in 22AEU.1 and in Clade 3, 15 in Clade 2, 11 in Alpha and Delta, 13 in Gamma, and 9 in Omicron. When compared, there was a reduction in the number of predicted epitopes concerning the Spike protein, mainly in the Delta and Omicron variants. These findings corroborate the need for updates seen today in bivalent mRNA vaccines against COVID-19 to promote a targeted immune response to the main circulating variant, Omicron, leading to more robust protection against this virus and avoiding cases of reinfection. When analyzing the specific epitopes for the RBD region of the spike protein, the Omicron variant did not present a B lymphocyte epitope from position 390, whereas the epitope at position 493 for MHC was predicted only for the Alpha, Gamma, and Omicron variants.
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Affiliation(s)
| | | | | | | | | | | | | | - Ana Isabel Vieira Fernandes
- Health Promotion Department of the Medical Sciences Center and Division for Infectious and Parasitic Diseases, Lauro Wanderley University Hospital, Federal University of Paraiba, Brazil
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2
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Tegally H, Wilkinson E, Tsui JLH, Moir M, Martin D, Brito AF, Giovanetti M, Khan K, Huber C, Bogoch II, San JE, Poongavanan J, Xavier JS, Candido DDS, Romero F, Baxter C, Pybus OG, Lessells RJ, Faria NR, Kraemer MUG, de Oliveira T. Dispersal patterns and influence of air travel during the global expansion of SARS-CoV-2 variants of concern. Cell 2023; 186:3277-3290.e16. [PMID: 37413988 PMCID: PMC10247138 DOI: 10.1016/j.cell.2023.06.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 05/31/2023] [Accepted: 06/02/2023] [Indexed: 07/08/2023]
Abstract
The Alpha, Beta, and Gamma SARS-CoV-2 variants of concern (VOCs) co-circulated globally during 2020 and 2021, fueling waves of infections. They were displaced by Delta during a third wave worldwide in 2021, which, in turn, was displaced by Omicron in late 2021. In this study, we use phylogenetic and phylogeographic methods to reconstruct the dispersal patterns of VOCs worldwide. We find that source-sink dynamics varied substantially by VOC and identify countries that acted as global and regional hubs of dissemination. We demonstrate the declining role of presumed origin countries of VOCs in their global dispersal, estimating that India contributed <15% of Delta exports and South Africa <1%-2% of Omicron dispersal. We estimate that >80 countries had received introductions of Omicron within 100 days of its emergence, associated with accelerated passenger air travel and higher transmissibility. Our study highlights the rapid dispersal of highly transmissible variants, with implications for genomic surveillance along the hierarchical airline network.
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Affiliation(s)
- Houriiyah Tegally
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa; KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa.
| | - Eduan Wilkinson
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa
| | | | - Monika Moir
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa
| | - Darren Martin
- Wellcome Centre for Infectious Diseases Research in Africa (CIDRI-Africa), Cape Town, South Africa; Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | | | - Marta Giovanetti
- Laboratorio de Flavivirus, Fundacao Oswaldo Cruz, Rio de Janeiro, Brazil; Laboratório de Genética Celular e Molecular, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Department of Science and Technology for Humans and the Environment, University of Campus Bio-Medico di Roma, Rome, Italy
| | - Kamran Khan
- BlueDot, Toronto, ON, Canada; Department of Medicine, Division of Infectious Diseases, University of Toronto, Toronto, ON, Canada
| | | | - Isaac I Bogoch
- Department of Medicine, Division of Infectious Diseases, University of Toronto, Toronto, ON, Canada
| | - James Emmanuel San
- KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa
| | - Jenicca Poongavanan
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa
| | - Joicymara S Xavier
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa; Universidade Federal de Minas Gerais, Belo Horizonte, Brazil; Institute of Agricultural Sciences, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Unaí, Brazil
| | - Darlan da S Candido
- MRC Centre for Global Infectious Disease Analysis and Department of Infectious Disease Epidemiology, Jameel Institute, School of Public Health, Imperial College London, London, UK
| | - Filipe Romero
- MRC Centre for Global Infectious Disease Analysis and Department of Infectious Disease Epidemiology, Jameel Institute, School of Public Health, Imperial College London, London, UK
| | - Cheryl Baxter
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa
| | - Oliver G Pybus
- Department of Biology, University of Oxford, Oxford, UK; Pandemic Sciences Institute, University of Oxford, Oxford, UK; Department of Pathobiology and Population Sciences, Royal Veterinary College London, London, UK
| | - Richard J Lessells
- KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa
| | - Nuno R Faria
- Department of Biology, University of Oxford, Oxford, UK; MRC Centre for Global Infectious Disease Analysis and Department of Infectious Disease Epidemiology, Jameel Institute, School of Public Health, Imperial College London, London, UK; Departamento de Moléstias Infecciosas e Parasitárias e Instituto de Medicina Tropical da Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Moritz U G Kraemer
- Department of Biology, University of Oxford, Oxford, UK; Pandemic Sciences Institute, University of Oxford, Oxford, UK.
| | - Tulio de Oliveira
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa; KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa; Department of Global Health, University of Washington, Seattle, WA, USA.
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3
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Grobusch MP, Weld L, Schnyder JL, Larsen CS, Lindner AK, Popescu CP, Huits R, Goorhuis A, Gautret P, Schlagenhauf P. COVID-19 impact on EuroTravNet infectious diseases sentinel surveillance in Europe. Travel Med Infect Dis 2023; 53:102583. [PMID: 37207977 DOI: 10.1016/j.tmaid.2023.102583] [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: 01/25/2023] [Revised: 04/19/2023] [Accepted: 05/03/2023] [Indexed: 05/21/2023]
Abstract
BACKGROUND The COVID-19 pandemic resulted in a sharp decline of post-travel patient encounters at the European sentinel surveillance network (EuroTravNet) of travellers' health. We report on the impact of COVID-19 on travel-related infectious diseases as recorded by EuroTravNet clinics. METHODS Travelers who presented between January 1, 2019 and September 30, 2021 were included. Comparisons were made between the pre-pandemic period (14 months from January 1, 2019 to February 29, 2020); and the pandemic period (19 months from March 1, 2020 to September 30, 2021). RESULTS Of the 15,124 visits to the network during the 33-month observation period, 10,941 (72%) were during the pre-pandemic period, and 4183 (28%) during the pandemic period. Average monthly visits declined from 782/month (pre-COVID-19 era) to 220/month (COVID-19 pandemic era). Among non-migrants the top-10 countries of exposure changed after onset of the COVID-19 pandemic; destinations such as Italy and Austria, where COVID-19 exposure peaked in the first months, replaced typical travel destinations in Asia (Thailand, Indonesia, India). There was a small decline in migrant patients reported, with little change in the top countries of exposure (Bolivia, Mali). The three top diagnoses with the largest overall decreases in relative frequency were acute gastroenteritis (-5.3%), rabies post-exposure prophylaxis (-2.8%), and dengue (-2.6%). Apart from COVID-19 (which rose from 0.1% to 12.7%), the three top diagnoses with the largest overall relative frequency increase were schistosomiasis (+4.9%), strongyloidiasis (+2.7%), and latent tuberculosis (+2.4%). CONCLUSIONS A marked COVID-19 pandemic-induced decline in global travel activities is reflected in reduced travel-related infectious diseases sentinel surveillance reporting.
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Affiliation(s)
- Martin P Grobusch
- Center for Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam, the Netherlands.
| | - Leisa Weld
- Statistical Consultant, Geneva, Switzerland
| | - Jenny L Schnyder
- Center for Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam, the Netherlands
| | | | - Andreas K Lindner
- Charité-Universitätsmedizin Berlin, Charité Center for Global Health, Institute of International Health, Berlin, Germany
| | - Corneliu Petru Popescu
- Carol Davila University of Medicine and Pharmacy, Bucharest, Romania; Dr Victor Babes Clinical Hospital of Infectious and Tropical Diseases, Bucharest, Romania
| | - Ralph Huits
- Department of Infectious Tropical Diseases and Microbiology, IRCCS Sacro Cuore Don Calabria Hospital, Negrar, Verona, Italy
| | - A Goorhuis
- Center for Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Amsterdam University Medical Centers, Location AMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Philippe Gautret
- IHU Méditerranée Infection, And Aix Marseille University, IRD, AP-HM, SSA, VITROME, Marseille, France
| | - Patricia Schlagenhauf
- WHO Collaborating Centre for Travellers' Health, Department of Global and Public Health, Epidemiology, Biostatistics and Prevention Institute, University of Zürich, Zürich, Switzerland
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Evaluating Data Sharing of SARS-CoV-2 Genomes for Molecular Epidemiology across the COVID-19 Pandemic. Viruses 2023; 15:v15020560. [PMID: 36851774 PMCID: PMC9959893 DOI: 10.3390/v15020560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/12/2023] [Accepted: 02/16/2023] [Indexed: 02/22/2023] Open
Abstract
Following the emergence of COVID-19 in December 2019, caused by the coronavirus SARS-CoV-2, the disease spread dramatically worldwide. The use of genomics to trace the dissemination of the virus and the identification of novel variants was essential in defining measures for containing the disease. We aim to evaluate the global effort to genomically characterize the circulating lineages of SARS-CoV-2, considering the data deposited in GISAID, the major platform for data sharing in a massive worldwide collaborative undertaking. We contextualize data for nearly three years (January 2020-October 2022) for the major contributing countries, percentage of characterized isolates and time for data processing in the context of the global pandemic. Within this collaborative effort, we also evaluated the early detection of seven major SARS-CoV-2 lineages, G, GR, GH, GK, GV, GRY and GRA. While Europe and the USA, following an initial period, showed positive results across time in terms of cases sequenced and time for data deposition, this effort is heterogeneous worldwide. Given the current immunization the major threat is the appearance of variants that evade the acquired immunity. In that scenario, the monitoring of those hypothetical variants will still play an essential role.
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5
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Tegally H, Wilkinson E, Martin D, Moir M, Brito A, Giovanetti M, Khan K, Huber C, Bogoch II, San JE, Tsui JLH, Poongavanan J, Xavier JS, Candido DDS, Romero F, Baxter C, Pybus OG, Lessells R, Faria NR, Kraemer MUG, de Oliveira T. Global Expansion of SARS-CoV-2 Variants of Concern: Dispersal Patterns and Influence of Air Travel. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2022:2022.11.22.22282629. [PMID: 36451885 PMCID: PMC9709793 DOI: 10.1101/2022.11.22.22282629] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
In many regions of the world, the Alpha, Beta and Gamma SARS-CoV-2 Variants of Concern (VOCs) co-circulated during 2020-21 and fueled waves of infections. During 2021, these variants were almost completely displaced by the Delta variant, causing a third wave of infections worldwide. This phenomenon of global viral lineage displacement was observed again in late 2021, when the Omicron variant disseminated globally. In this study, we use phylogenetic and phylogeographic methods to reconstruct the dispersal patterns of SARS-CoV-2 VOCs worldwide. We find that the source-sink dynamics of SARS-CoV-2 varied substantially by VOC, and identify countries that acted as global hubs of variant dissemination, while other countries became regional contributors to the export of specific variants. We demonstrate a declining role of presumed origin countries of VOCs to their global dispersal: we estimate that India contributed <15% of all global exports of Delta to other countries and South Africa <1-2% of all global Omicron exports globally. We further estimate that >80 countries had received introductions of Omicron BA.1 100 days after its inferred date of emergence, compared to just over 25 countries for the Alpha variant. This increased speed of global dissemination was associated with a rebound in air travel volume prior to Omicron emergence in addition to the higher transmissibility of Omicron relative to Alpha. Our study highlights the importance of global and regional hubs in VOC dispersal, and the speed at which highly transmissible variants disseminate through these hubs, even before their detection and characterization through genomic surveillance. Highlights Global phylogenetic analysis reveals relationship between air travel and speed of dispersal of SARS-CoV-2 variants of concern (VOCs)Omicron VOC spread to 5x more countries within 100 days of its emergence compared to all other VOCsOnward transmission and dissemination of VOCs Delta and Omicron was primarily from secondary hubs rather than initial country of detection during a time of increased global air travelAnalysis highlights highly connected countries identified as major global and regional exporters of VOCs.
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Affiliation(s)
- Houriiyah Tegally
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa
- KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa
| | - Eduan Wilkinson
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa
| | - Darren Martin
- Wellcome Centre for Infectious Diseases Research in Africa (CIDRI-Africa), Cape Town, South Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Monika Moir
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa
| | - Anderson Brito
- Instituto Todos pela Saúde, São Paulo, São Paulo, Brazil
| | - Marta Giovanetti
- Laboratorio de Flavivirus, Fundacao Oswaldo Cruz, Rio de Janeiro, Brazil
- Laboratório de Genética Celular e Molecular, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
- Department of Science and Technology for Humans and the Environment, University of Campus Bio-Medico di Roma, Rome, Italy
| | - Kamran Khan
- BlueDot, Toronto, Canada
- Department of Medicine, Division of Infectious Diseases, University of Toronto, Toronto, Canada
| | | | - Isaac I Bogoch
- Department of Medicine, Division of Infectious Diseases, University of Toronto, Toronto, Canada
| | - James Emmanuel San
- KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa
| | | | - Jenicca Poongavanan
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa
| | - Joicymara S Xavier
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa
- Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
- Institute of Agricultural Sciences, Universidade Federal dos Vales do Jequitinhonha e Mucuri, Unaí, Brazil
| | - Darlan da S Candido
- MRC Centre for Global Infectious Disease Analysis and Department of Infectious Disease Epidemiology, Jameel Institute, School of Public Health, Imperial College London, London, UK
| | - Filipe Romero
- MRC Centre for Global Infectious Disease Analysis and Department of Infectious Disease Epidemiology, Jameel Institute, School of Public Health, Imperial College London, London, UK
| | - Cheryl Baxter
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa
| | - Oliver G Pybus
- Department of Biology, University of Oxford, Oxford, UK
- Pandemic Sciences Institute, University of Oxford, Oxford, UK
- Department of Pathobiology and Population Sciences, Royal Veterinary College London, London, UK
| | - Richard Lessells
- KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa
| | - Nuno R Faria
- MRC Centre for Global Infectious Disease Analysis and Department of Infectious Disease Epidemiology, Jameel Institute, School of Public Health, Imperial College London, London, UK
- Departamento de Moléstias Infecciosas e Parasitárias e Instituto de Medicina Tropical da Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
- Department of Biology, University of Oxford, Oxford, UK
| | - Moritz U G Kraemer
- Department of Biology, University of Oxford, Oxford, UK
- Pandemic Sciences Institute, University of Oxford, Oxford, UK
| | - Tulio de Oliveira
- Centre for Epidemic Response and Innovation (CERI), School of Data Science and Computational Thinking, Stellenbosch University, Stellenbosch, South Africa
- KwaZulu-Natal Research Innovation and Sequencing Platform (KRISP), Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa
- Department of Global Health, University of Washington, Seattle, WA, USA
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6
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Gao L, Zheng C, Shi Q, Xiao K, Wang L, Liu Z, Li Z, Dong X. Evolving trend change during the COVID-19 pandemic. Front Public Health 2022; 10:957265. [PMID: 36203708 PMCID: PMC9531778 DOI: 10.3389/fpubh.2022.957265] [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: 05/30/2022] [Accepted: 08/12/2022] [Indexed: 01/24/2023] Open
Abstract
Coronavirus disease (COVID-19) has caused unimaginable damage to public health and socio-economic structures worldwide; thus, an epidemiological depiction of the global evolving trends of this disease is necessary. As of March 31, 2022, the number of cases increased gradually over the four waves of the COVID-19 pandemic, indicating the need for continuous countermeasures. The highest total cases per million and total deaths per million were observed in Europe (240,656.542) and South America (2,912.229), despite these developed countries having higher vaccination rates than other continents, such as Africa. In contrast, the lowest of the above two indices were found in undeveloped African countries, which had the lowest number of vaccinations. These data indicate that the COVID-19 pandemic is positively related to the socio-economic development level; meanwhile, the data suggest that the vaccine currently used in these continents cannot completely prevent the spread of COVID-19. Thus, rethinking the feasibility of a single vaccine to control the disease is needed. Although the number of cases in the fourth wave increased exponentially compared to those of the first wave, ~43.1% of deaths were observed during the first wave. This was not only closely linked to multiple factors, including the inadequate preparation for the initial response to the COVID-19 pandemic, the gradual reduction in the severity of additional variants, and the protection conferred by prior infection and/or vaccination, but this also indicated the change in the main driving dynamic in the fourth wave. Moreover, at least 12 variants were observed globally, showing a clear spatiotemporal profile, which provides the best explanation for the presence of the four waves of the pandemic. Furthermore, there was a clear shift in the trend from multiple variants driving the spread of disease in the early stage of the pandemic to a single Omicron lineage predominating in the fourth wave. These data suggest that the Omicron variant has an advantage in transmissibility over other contemporary co-circulating variants, demonstrating that monitoring new variants is key to reducing further spread. We recommend that public health measures, along with vaccination and testing, are continually implemented to stop the COVID-19 pandemic.
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Affiliation(s)
- Liping Gao
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Canjun Zheng
- Chinese Center for Disease Control and Prevention, Beijing, China
| | - Qi Shi
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Kang Xiao
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China
| | - Lili Wang
- Chinese Center for Disease Control and Prevention, Beijing, China
| | - Zhiguo Liu
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China,*Correspondence: Zhiguo Liu
| | - Zhenjun Li
- Chinese Center for Disease Control and Prevention, Beijing, China,State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China,Zhenjun Li
| | - Xiaoping Dong
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China,Xiaoping Dong
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7
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Phylogeography of Sub-Saharan Mitochondrial Lineages Outside Africa Highlights the Roles of the Holocene Climate Changes and the Atlantic Slave Trade. Int J Mol Sci 2022; 23:ijms23169219. [PMID: 36012483 PMCID: PMC9408831 DOI: 10.3390/ijms23169219] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 08/14/2022] [Accepted: 08/15/2022] [Indexed: 12/03/2022] Open
Abstract
Despite the importance of ancient DNA for understanding human prehistoric dispersals, poor survival means that data remain sparse for many areas in the tropics, including in Africa. In such instances, analysis of contemporary genomes remains invaluable. One promising approach is founder analysis, which identifies and dates migration events in non-recombining systems. However, it has yet to be fully exploited as its application remains controversial. Here, we test the approach by evaluating the age of sub-Saharan mitogenome lineages sampled outside Africa. The analysis confirms that such lineages in the Americas date to recent centuries—the time of the Atlantic slave trade—thereby validating the approach. By contrast, in North Africa, Southwestern Asia and Europe, roughly half of the dispersal signal dates to the early Holocene, during the “greening” of the Sahara. We elaborate these results by showing that the main source regions for the two main dispersal episodes are distinct. For the recent dispersal, the major source was West Africa, but with two exceptions: South America, where the fraction from Southern Africa was greater, and Southwest Asia, where Eastern Africa was the primary source. These observations show the potential of founder analysis as both a supplement and complement to ancient DNA studies.
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8
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McBroome J, Martin J, de Bernardi Schneider A, Turakhia Y, Corbett-Detig R. Identifying SARS-CoV-2 regional introductions and transmission clusters in real time. Virus Evol 2022; 8:veac048. [PMID: 35769891 PMCID: PMC9214145 DOI: 10.1093/ve/veac048] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 04/04/2022] [Accepted: 06/13/2022] [Indexed: 12/31/2022] Open
Abstract
The unprecedented severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) global sequencing effort has suffered from an analytical bottleneck. Many existing methods for phylogenetic analysis are designed for sparse, static datasets and are too computationally expensive to apply to densely sampled, rapidly expanding datasets when results are needed immediately to inform public health action. For example, public health is often concerned with identifying clusters of closely related samples, but the sheer scale of the data prevents manual inspection and the current computational models are often too expensive in time and resources. Even when results are available, intuitive data exploration tools are of critical importance to effective public health interpretation and action. To help address this need, we present a phylogenetic heuristic that quickly and efficiently identifies newly introduced strains in a region, resulting in clusters of infected individuals, and their putative geographic origins. We show that this approach performs well on simulated data and yields results largely congruent with more sophisticated Bayesian phylogeographic modeling approaches. We also introduce Cluster-Tracker (https://clustertracker.gi.ucsc.edu/), a novel interactive web-based tool to facilitate effective and intuitive SARS-CoV-2 geographic data exploration and visualization across the USA. Cluster-Tracker is updated daily and automatically identifies and highlights groups of closely related SARS-CoV-2 infections resulting from the transmission of the virus between two geographic areas by travelers, streamlining public health tracking of local viral diversity and emerging infection clusters. The site is open-source and designed to be easily configured to analyze any chosen region, making it a useful resource globally. The combination of these open-source tools will empower detailed investigations of the geographic origins and spread of SARS-CoV-2 and other densely sampled pathogens.
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Affiliation(s)
- Jakob McBroome
- Biomolecular Engineering and Genomics Institute, University of California, Santa Cruz 1156 High St, Santa Cruz, CA 95064, USA
| | - Jennifer Martin
- Biomolecular Engineering and Genomics Institute, University of California, Santa Cruz 1156 High St, Santa Cruz, CA 95064, USA
| | - Adriano de Bernardi Schneider
- Biomolecular Engineering and Genomics Institute, University of California, Santa Cruz 1156 High St, Santa Cruz, CA 95064, USA
| | - Yatish Turakhia
- Electrical and Computer Engineering, University of California, San Diego 9500 Gilman Dr, La Jolla, CA 92093, USA
| | - Russell Corbett-Detig
- Biomolecular Engineering and Genomics Institute, University of California, Santa Cruz 1156 High St, Santa Cruz, CA 95064, USA
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9
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Liu P, Song Y, Colijn C, MacPherson A. The impact of sampling bias on viral phylogeographic reconstruction. PLOS GLOBAL PUBLIC HEALTH 2022; 2:e0000577. [PMID: 36962555 PMCID: PMC10021582 DOI: 10.1371/journal.pgph.0000577] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 08/16/2022] [Indexed: 11/18/2022]
Abstract
Genomic epidemiology plays an ever-increasing role in our understanding of and response to the spread of infectious pathogens. Phylogeography, the reconstruction of the historical location and movement of pathogens from the evolutionary relationships among sampled pathogen sequences, can inform policy decisions related to viral movement among jurisdictions. However, phylogeographic reconstruction is impacted by the fact that the sampling and virus sequencing policies differ among jurisdictions, and these differences can cause bias in phylogeographic reconstructions. Here we assess the potential impacts of geographic-based sampling bias on estimated viral locations in the past, and on whether key viral movements can be detected. We quantify the effect of bias using simulated phylogenies with known geographic histories, and determine the impact of the biased sampling and of the underlying migration rate on the accuracy of estimated past viral locations. We find that overall, the accuracy of phylogeographic reconstruction is high, particularly when the migration rate is low. However, results depend on sampling, and sampling bias can have a large impact on the numbers and nature of estimated migration events. We apply these insights to the geographic spread of Ebolavirus in the 2014-2016 West Africa epidemic. This work highlights how sampling policy can both impact geographic inference and be optimized to best ensure the accuracy of specific features of geographic spread.
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Affiliation(s)
- Pengyu Liu
- Department of Mathematics, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Yexuan Song
- Department of Mathematics, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Caroline Colijn
- Department of Mathematics, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Ailene MacPherson
- Department of Mathematics, Simon Fraser University, Burnaby, British Columbia, Canada
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10
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Emergence of B.1.524(G) SARS-CoV-2 in Malaysia during the third COVID-19 epidemic wave. Sci Rep 2021; 11:22105. [PMID: 34764315 PMCID: PMC8586159 DOI: 10.1038/s41598-021-01223-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 10/18/2021] [Indexed: 12/16/2022] Open
Abstract
The COVID-19 pandemic first emerged in Malaysia in Jan 2020. As of 12th Sept 2021, 1,979,698 COVID-19 cases that occurred over three major epidemic waves were confirmed. The virus contributing to the three epidemic waves has not been well-studied. We sequenced the genome of 22 SARS-CoV-2 strains detected in Malaysia during the second and the ongoing third wave of the COVID-19 epidemic. Detailed phylogenetic and genetic variation analyses of the SARS-CoV-2 isolate genomes were performed using these newly determined sequences and all other available sequences. Results from the analyses suggested multiple independent introductions of SARS-CoV-2 into Malaysia. A new B.1.524(G) lineage with S-D614G mutation was detected in Sabah, East Malaysia and Selangor, Peninsular Malaysia on 7th October 2020 and 14th October 2020, respectively. This new B.1.524(G) group was not the direct descendant of any of the previously detected lineages. The new B.1.524(G) carried a set of genetic variations, including A701V (position variant frequency = 0.0007) in Spike protein and a novel G114T mutation at the 5’UTR. The biological importance of the specific mutations remained unknown. The sequential appearance of the mutations, however, suggests that the spread of the new B.1.524(G) lineages likely begun in Sabah and then spread to Selangor. The findings presented here support the importance of SARS-CoV-2 full genome sequencing as a tool to establish an epidemiological link between cases or clusters of COVID-19 worldwide.
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11
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A Global Mutational Profile of SARS-CoV-2: A Systematic Review and Meta-Analysis of 368,316 COVID-19 Patients. Life (Basel) 2021; 11:life11111224. [PMID: 34833100 PMCID: PMC8620851 DOI: 10.3390/life11111224] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/03/2021] [Accepted: 11/08/2021] [Indexed: 12/20/2022] Open
Abstract
Since its first detection in December 2019, more than 232 million cases of COVID-19, including 4.7 million deaths, have been reported by the WHO. The SARS-CoV-2 viral genomes have evolved rapidly worldwide, causing the emergence of new variants. This systematic review and meta-analysis was conducted to provide a global mutational profile of SARS-CoV-2 from December 2019 to October 2020. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA), and a study protocol was lodged with PROSPERO. Data from 62 eligible studies involving 368,316 SARS-CoV-2 genomes were analyzed. The mutational data analyzed showed most studies detected mutations in the Spike protein (n = 50), Nucleocapsid phosphoprotein (n = 34), ORF1ab gene (n = 29), 5′-UTR (n = 28) and ORF3a (n = 25). Under the random-effects model, pooled prevalence of SARS-CoV-2 variants was estimated at 95.1% (95% CI; 93.3–96.4%; I2 = 98.952%; p = 0.000) while subgroup meta-analysis by country showed majority of the studies were conducted ‘Worldwide’ (n = 10), followed by ‘Multiple countries’ (n = 6) and the USA (n = 5). The estimated prevalence indicated a need to continuously monitor the prevalence of new mutations due to their potential influence on disease severity, transmissibility and vaccine effectiveness.
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12
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Xia X. Dating the Common Ancestor from an NCBI Tree of 83688 High-Quality and Full-Length SARS-CoV-2 Genomes. Viruses 2021; 13:1790. [PMID: 34578371 PMCID: PMC8472983 DOI: 10.3390/v13091790] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/06/2021] [Accepted: 09/06/2021] [Indexed: 02/04/2023] Open
Abstract
All dating studies involving SARS-CoV-2 are problematic. Previous studies have dated the most recent common ancestor (MRCA) between SARS-CoV-2 and its close relatives from bats and pangolins. However, the evolutionary rate thus derived is expected to differ from the rate estimated from sequence divergence of SARS-CoV-2 lineages. Here, I present dating results for the first time from a large phylogenetic tree with 86,582 high-quality full-length SARS-CoV-2 genomes. The tree contains 83,688 genomes with full specification of collection time. Such a large tree spanning a period of about 1.5 years offers an excellent opportunity for dating the MRCA of the sampled SARS-CoV-2 genomes. The MRCA is dated 16 August 2019, with the evolutionary rate estimated to be 0.05526 mutations/genome/day. The Pearson correlation coefficient (r) between the root-to-tip distance (D) and the collection time (T) is 0.86295. The NCBI tree also includes 10 SARS-CoV-2 genomes isolated from cats, collected over roughly the same time span as human COVID-19 infection. The MRCA from these cat-derived SARS-CoV-2 is dated 30 July 2019, with r = 0.98464. While the dating method is well known, I have included detailed illustrations so that anyone can repeat the analysis and obtain the same dating results. With 16 August 2019 as the date of the MRCA of sampled SARS-CoV-2 genomes, archived samples from respiratory or digestive tracts collected around or before 16 August 2019, or those that are not descendants of the existing SARS-CoV-2 lineages, should be particularly valuable for tracing the origin of SARS-CoV-2.
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Affiliation(s)
- Xuhua Xia
- Department of Biology, University of Ottawa, Marie-Curie Private, Ottawa, ON K1N 9A7, Canada; ; Tel.: +1-613-562-5718
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, ON K1H 8M5, Canada
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13
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Intercontinental transmission and local demographic expansion of SARS-CoV-2. Epidemiol Infect 2021; 149:e94. [PMID: 33845928 PMCID: PMC8060534 DOI: 10.1017/s0950268821000777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The global outbreak of coronavirus disease 2019 (COVID-19) is greatly threatening the public health in the world. We reconstructed global transmissions and potential demographic expansions of severe acute respiratory syndrome coronavirus 2 based on genomic information. We found that intercontinental transmissions were rare in January and early February but drastically increased since late February. After world-wide implements of travel restrictions, the transmission frequencies decreased to a low level in April. We identified a total of 88 potential demographic expansions over the world based on the star-radiative networks and 75 of them were found in Europe and North America. The expansion numbers peaked in March and quickly dropped since April. These findings are highly concordant with epidemic reports and modelling results and highlight the significance of quarantine validity on the global spread of COVID-19. Our analyses indicate that the travel restrictions and social distancing measures are effective in containing the spread of COVID-19.
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14
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Rokić F, Trgovec-Greif L, Sučić N, Čemeljić N, Grbeša ĐC, Svedružić Ž, Rukavina T, Vugrek O, Jurak I. Diverse SARS-CoV-2 variants preceded the initial COVID-19 outbreak in Croatia. Arch Virol 2021; 166:1735-1739. [PMID: 33761008 PMCID: PMC7988246 DOI: 10.1007/s00705-021-05029-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 01/21/2021] [Indexed: 11/18/2022]
Abstract
We developed a next-generation SARS-CoV-2 sequencing platform and obtained the first SARS-CoV-2 sequences from patients in Croatia at the beginning of the COVID-19 outbreak in the spring of 2020. Integrating the sequencing and the epidemiological data, we show that patients were infected with different SARS-CoV-2 variants belonging to different clades (mostly G and GH). This result confirms that there was widespread virus transmission early in 2020. Interestingly, we identified a unique mutation resulting in a V13I substitution in Nsp5A, the main viral protease, in a patient who had not received antiviral therapy.
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Affiliation(s)
- Filip Rokić
- Laboratory for Advanced Genomics, Ruđer Bošković Institute, Zagreb, Croatia
| | | | - Neven Sučić
- Teaching Institute for Public Health, Rijeka, Croatia
| | - Noa Čemeljić
- Master's Programme in Biomedicine, Karolinska Institutet, Stockholm, Sweden.,Department of Biotechnology, University of Rijeka, Rijeka, Croatia
| | - Đurđica Cekinović Grbeša
- Faculty of Medicine in Rijeka, University of Rijeka, Rijeka, Croatia.,Department of Infectious Diseases, University Hospital Rijeka, Rijeka, Croatia
| | - Željko Svedružić
- Department of Biotechnology, University of Rijeka, Rijeka, Croatia
| | - Tomislav Rukavina
- Teaching Institute for Public Health, Rijeka, Croatia.,Faculty of Medicine in Rijeka, University of Rijeka, Rijeka, Croatia
| | - Oliver Vugrek
- Laboratory for Advanced Genomics, Ruđer Bošković Institute, Zagreb, Croatia.
| | - Igor Jurak
- Department of Biotechnology, University of Rijeka, Rijeka, Croatia.
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15
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Radhakrishnan C, Divakar MK, Jain A, Viswanathan P, Bhoyar RC, Jolly B, Imran M, Sharma D, Rophina M, Ranjan G, Sehgal P, Jose BP, Raman RV, Kesavan TN, George K, Mathew S, Poovullathil JK, Keeriyatt Govindan SK, Nair PR, Vadekkandiyil S, Gladson V, Mohan M, Parambath FC, Mangla M, Shamnath A, Sivasubbu S, Scaria V. Initial Insights Into the Genetic Epidemiology of SARS-CoV-2 Isolates From Kerala Suggest Local Spread From Limited Introductions. Front Genet 2021; 12:630542. [PMID: 33815467 PMCID: PMC8010186 DOI: 10.3389/fgene.2021.630542] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 02/12/2021] [Indexed: 12/04/2022] Open
Abstract
Coronavirus disease 2019 (COVID-19) rapidly spread from a city in China to almost every country in the world, affecting millions of individuals. The rapid increase in the COVID-19 cases in the state of Kerala in India has necessitated the understanding of SARS-CoV-2 genetic epidemiology. We sequenced 200 samples from patients in Kerala using COVIDSeq protocol amplicon-based sequencing. The analysis identified 166 high-quality single-nucleotide variants encompassing four novel variants and 89 new variants in the Indian isolated SARS-CoV-2. Phylogenetic and haplotype analysis revealed that the virus was dominated by three distinct introductions followed by local spread suggesting recent outbreaks and that it belongs to the A2a clade. Further analysis of the functional variants revealed that two variants in the S gene associated with increased infectivity and five variants mapped in primer binding sites affect the efficacy of RT-PCR. To the best of our knowledge, this is the first and most comprehensive report of SARS-CoV-2 genetic epidemiology from Kerala.
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Affiliation(s)
| | - Mohit Kumar Divakar
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research, Ghaziabad, India
| | - Abhinav Jain
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research, Ghaziabad, India
| | | | - Rahul C. Bhoyar
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Bani Jolly
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research, Ghaziabad, India
| | - Mohamed Imran
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research, Ghaziabad, India
| | - Disha Sharma
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
| | - Mercy Rophina
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research, Ghaziabad, India
| | - Gyan Ranjan
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research, Ghaziabad, India
| | - Paras Sehgal
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research, Ghaziabad, India
| | | | | | | | | | | | | | | | | | | | | | | | | | - Mohit Mangla
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research, Ghaziabad, India
| | - Afra Shamnath
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
| | | | - Sridhar Sivasubbu
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research, Ghaziabad, India
| | - Vinod Scaria
- Council of Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, New Delhi, India
- Academy of Scientific and Innovative Research, Ghaziabad, India
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16
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Dynamics of a Dual SARS-CoV-2 Lineage Co-Infection on a Prolonged Viral Shedding COVID-19 Case: Insights into Clinical Severity and Disease Duration. Microorganisms 2021; 9:microorganisms9020300. [PMID: 33540596 PMCID: PMC7912897 DOI: 10.3390/microorganisms9020300] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 01/27/2021] [Accepted: 01/28/2021] [Indexed: 12/12/2022] Open
Abstract
A few molecularly proven severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cases of symptomatic reinfection are currently known worldwide, with a resolved first infection followed by a second infection after a 48 to 142-day intervening period. We report a multiple-component study of a clinically severe and prolonged viral shedding coronavirus disease 2019 (COVID-19) case in a 17-year-old Portuguese female. She had two hospitalizations, a total of 19 RT-PCR tests, mostly positive, and criteria for releasing from home isolation at the end of 97 days. The viral genome was sequenced in seven serial samples and in the diagnostic sample from her infected mother. A human genome-wide array (>900 K) was screened on the seven samples, and in vitro culture was conducted on isolates from three late samples. The patient had co-infection by two SARS-CoV-2 lineages, which were affiliated in distinct clades and diverging by six variants. The 20A lineage was absolute at the diagnosis (shared with the patient’s mother), but nine days later, the 20B lineage had 3% frequency, and two months later, the 20B lineage had 100% frequency. The 900 K profiles confirmed the identity of the patient in the serial samples, and they allowed us to infer that she had polygenic risk scores for hospitalization and severe respiratory disease within the normal distributions for a Portuguese population cohort. The early-on dynamic co-infection may have contributed to the severity of COVID-19 in this otherwise healthy young patient, and to her prolonged SARS-CoV-2 shedding profile.
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