RESUMEN
The past year has underscored the threat that emerging viruses pose to global health. The 2021 John Dirks Canada Gairdner Global Health award recognizes the contributions of Joseph Sriyal Malik Peiris and Yi Guan toward understanding the origins and options for control of newly emerging infectious disease outbreaks in Asia, notably zoonotic influenza and severe acute respiratory syndrome (SARS). Nicole Neuman of Cell corresponded with Malik Peiris about his path to studying emerging infectious diseases and the challenges of this work. Excerpts of their exchange are included here.
Asunto(s)
Enfermedades Transmisibles/epidemiología , Salud Global , COVID-19/epidemiología , COVID-19/virología , Enfermedades Transmisibles/patología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/patología , Brotes de Enfermedades , Humanos , Gripe Humana/epidemiología , Gripe Humana/patología , SARS-CoV-2/aislamiento & purificaciónRESUMEN
Tragic events such as pandemics can be remembered as well as foreshadowed by works of art. Paintings by the artists Edvard Munch and John Singer Sargent (1918-19) tell us in real time what it was like to be stricken by the Spanish flu. Paintings by Edward Hopper (1940s and '50s) foretell the lockdown and social distancing of today's COVID-19 pandemic.
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Infecciones por Coronavirus , Influenza Pandémica, 1918-1919 , Medicina en las Artes , Pandemias , Neumonía Viral , COVID-19 , Infecciones por Coronavirus/epidemiología , Brotes de Enfermedades , Personajes , Historia del Siglo XX , Humanos , Gripe Humana/epidemiología , Neumonía Viral/epidemiología , Primera Guerra MundialRESUMEN
Coronavirus disease 2019 (COVID-19) is caused by SARS-CoV-2 infection and was first reported in central China in December 2019. Extensive molecular surveillance in Guangdong, China's most populous province, during early 2020 resulted in 1,388 reported RNA-positive cases from 1.6 million tests. In order to understand the molecular epidemiology and genetic diversity of SARS-CoV-2 in China, we generated 53 genomes from infected individuals in Guangdong using a combination of metagenomic sequencing and tiling amplicon approaches. Combined epidemiological and phylogenetic analyses indicate multiple independent introductions to Guangdong, although phylogenetic clustering is uncertain because of low virus genetic variation early in the pandemic. Our results illustrate how the timing, size, and duration of putative local transmission chains were constrained by national travel restrictions and by the province's large-scale intensive surveillance and intervention measures. Despite these successes, COVID-19 surveillance in Guangdong is still required, because the number of cases imported from other countries has increased.
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Betacoronavirus/genética , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Teorema de Bayes , COVID-19 , China/epidemiología , Infecciones por Coronavirus/virología , Monitoreo Epidemiológico , Humanos , Funciones de Verosimilitud , Pandemias , Neumonía Viral/virología , SARS-CoV-2 , ViajeRESUMEN
SARS-CoV-2 infection displays immense inter-individual clinical variability, ranging from silent infection to lethal disease. The role of human genetics in determining clinical response to the virus remains unclear. Studies of outliers-individuals remaining uninfected despite viral exposure and healthy young patients with life-threatening disease-present a unique opportunity to reveal human genetic determinants of infection and disease.
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Infecciones por Coronavirus/genética , Infecciones por Coronavirus/inmunología , Predisposición Genética a la Enfermedad , Neumonía Viral/genética , Neumonía Viral/inmunología , Factores de Edad , Betacoronavirus/fisiología , COVID-19 , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/fisiopatología , Resistencia a la Enfermedad , Estudios de Asociación Genética , Enfermedades Genéticas Congénitas/inmunología , Variación Genética , Genoma Humano , Interacciones Huésped-Patógeno , Humanos , Infecciones/genética , Infecciones/inmunología , Infecciones/fisiopatología , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/fisiopatología , SARS-CoV-2RESUMEN
The novel coronavirus SARS-CoV-2 was first detected in the Pacific Northwest region of the United States in January 2020, with subsequent COVID-19 outbreaks detected in all 50 states by early March. To uncover the sources of SARS-CoV-2 introductions and patterns of spread within the United States, we sequenced nine viral genomes from early reported COVID-19 patients in Connecticut. Our phylogenetic analysis places the majority of these genomes with viruses sequenced from Washington state. By coupling our genomic data with domestic and international travel patterns, we show that early SARS-CoV-2 transmission in Connecticut was likely driven by domestic introductions. Moreover, the risk of domestic importation to Connecticut exceeded that of international importation by mid-March regardless of our estimated effects of federal travel restrictions. This study provides evidence of widespread sustained transmission of SARS-CoV-2 within the United States and highlights the critical need for local surveillance.
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Betacoronavirus/genética , Infecciones por Coronavirus/transmisión , Neumonía Viral/transmisión , Viaje , Betacoronavirus/aislamiento & purificación , COVID-19 , Connecticut/epidemiología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Monitoreo Epidemiológico , Humanos , Funciones de Verosimilitud , Pandemias , Filogenia , Neumonía Viral/epidemiología , Neumonía Viral/virología , SARS-CoV-2 , Viaje/legislación & jurisprudencia , Estados Unidos/epidemiología , Washingtón/epidemiologíaRESUMEN
Infectious diseases prevalent in humans and animals are caused by pathogens that once emerged from other animal hosts. In addition to these established infections, new infectious diseases periodically emerge. In extreme cases they may cause pandemics such as COVID-19; in other cases, dead-end infections or smaller epidemics result. Established diseases may also re-emerge, for example by extending geographically or by becoming more transmissible or more pathogenic. Disease emergence reflects dynamic balances and imbalances, within complex globally distributed ecosystems comprising humans, animals, pathogens, and the environment. Understanding these variables is a necessary step in controlling future devastating disease emergences.
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Enfermedades Transmisibles Emergentes/epidemiología , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , COVID-19 , Enfermedades Transmisibles Emergentes/prevención & control , Enfermedades Transmisibles Emergentes/transmisión , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/transmisión , Demografía , Ambiente , Interacciones Huésped-Patógeno , Humanos , Pandemias/prevención & control , Neumonía Viral/prevención & control , Neumonía Viral/transmisiónRESUMEN
Operation Outbreak (OO) is a Bluetooth-based simulation platform that teaches students how pathogens spread and the impact of interventions, thereby facilitating the safe reopening of schools. OO also generates data to inform epidemiological models and prevent future outbreaks. Before SARS-CoV-2 was reported, we repeatedly simulated a virus with similar features, correctly predicting many human behaviors later observed during the pandemic.
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Simulación por Computador , Instrucción por Computador/métodos , Trazado de Contacto/métodos , Infecciones por Coronavirus/epidemiología , Epidemiología/educación , Neumonía Viral/epidemiología , Número Básico de Reproducción , COVID-19 , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/transmisión , Humanos , Aplicaciones Móviles , Pandemias/prevención & control , Neumonía Viral/prevención & control , Neumonía Viral/transmisión , Teléfono InteligenteRESUMEN
A SARS-CoV-2 variant carrying the Spike protein amino acid change D614G has become the most prevalent form in the global pandemic. Dynamic tracking of variant frequencies revealed a recurrent pattern of G614 increase at multiple geographic levels: national, regional, and municipal. The shift occurred even in local epidemics where the original D614 form was well established prior to introduction of the G614 variant. The consistency of this pattern was highly statistically significant, suggesting that the G614 variant may have a fitness advantage. We found that the G614 variant grows to a higher titer as pseudotyped virions. In infected individuals, G614 is associated with lower RT-PCR cycle thresholds, suggestive of higher upper respiratory tract viral loads, but not with increased disease severity. These findings illuminate changes important for a mechanistic understanding of the virus and support continuing surveillance of Spike mutations to aid with development of immunological interventions.
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Betacoronavirus/genética , Betacoronavirus/patogenicidad , Infecciones por Coronavirus/virología , Neumonía Viral/virología , Glicoproteína de la Espiga del Coronavirus/genética , COVID-19 , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/fisiopatología , Monitoreo Epidemiológico , Aptitud Genética , Variación Genética , Sistemas de Información Geográfica , Hospitalización , Humanos , Pandemias , Filogenia , Neumonía Viral/epidemiología , Neumonía Viral/fisiopatología , Sistema Respiratorio/virología , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Carga ViralAsunto(s)
Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/etiología , Coronavirus/patogenicidad , Neumonía Viral/epidemiología , Neumonía Viral/etiología , Betacoronavirus/metabolismo , Betacoronavirus/patogenicidad , COVID-19 , Coronavirus/metabolismo , Brotes de Enfermedades , Humanos , Pandemias , SARS-CoV-2RESUMEN
The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated disease, COVID-19, has demonstrated the devastating impact of a novel, infectious pathogen on a susceptible population. Here, we explain the basic concepts of herd immunity and discuss its implications in the context of COVID-19.
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Infecciones por Coronavirus/inmunología , Inmunidad Colectiva , Modelos Inmunológicos , Neumonía Viral/inmunología , Número Básico de Reproducción , Betacoronavirus/inmunología , COVID-19 , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Salud Global , Humanos , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/transmisión , SARS-CoV-2 , Vacunación , Cobertura de VacunaciónRESUMEN
SARS-CoV-2, the causal agent of COVID-19, first emerged in late 2019 in China. It has since infected more than 870,000 individuals and caused more than 43,000 deaths globally. Here, we discuss therapeutic and prophylactic interventions for SARS-CoV-2 with a focus on vaccine development and its challenges. Vaccines are being rapidly developed but will likely come too late to affect the first wave of a potential pandemic. Nevertheless, critical lessons can be learned for the development of vaccines against rapidly emerging viruses. Importantly, SARS-CoV-2 vaccines will be essential to reducing morbidity and mortality if the virus establishes itself in the population.
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Betacoronavirus/patogenicidad , Infecciones por Coronavirus/prevención & control , Desarrollo de Medicamentos , Pandemias/prevención & control , Neumonía Viral/prevención & control , Vacunas Virales , Animales , Betacoronavirus/inmunología , COVID-19 , Vacunas contra la COVID-19 , China , Ensayos Clínicos como Asunto , Coronavirus/patogenicidad , Infecciones por Coronavirus/epidemiología , Modelos Animales de Enfermedad , Humanos , Neumonía Viral/epidemiología , SARS-CoV-2 , Factores de Tiempo , Vacunas Virales/uso terapéuticoRESUMEN
We conducted a serological study to define correlates of immunity against SARS-CoV-2. Compared to those with mild coronavirus disease 2019 (COVID-19) cases, individuals with severe disease exhibited elevated virus-neutralizing titers and antibodies against the nucleocapsid (N) and the receptor binding domain (RBD) of the spike protein. Age and sex played lesser roles. All cases, including asymptomatic individuals, seroconverted by 2 weeks after PCR confirmation. Spike RBD and S2 and neutralizing antibodies remained detectable through 5-7 months after onset, whereas α-N titers diminished. Testing 5,882 members of the local community revealed only 1 sample with seroreactivity to both RBD and S2 that lacked neutralizing antibodies. This fidelity could not be achieved with either RBD or S2 alone. Thus, inclusion of multiple independent assays improved the accuracy of antibody tests in low-seroprevalence communities and revealed differences in antibody kinetics depending on the antigen. We conclude that neutralizing antibodies are stably produced for at least 5-7 months after SARS-CoV-2 infection.
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Betacoronavirus/inmunología , Técnicas de Laboratorio Clínico/métodos , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/inmunología , Inmunidad Humoral , Neumonía Viral/epidemiología , Neumonía Viral/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Arizona/epidemiología , Betacoronavirus/aislamiento & purificación , COVID-19 , Prueba de COVID-19 , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/diagnóstico , Proteínas de la Nucleocápside de Coronavirus , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteínas de la Nucleocápside/inmunología , Pandemias , Fosfoproteínas , Neumonía Viral/sangre , Neumonía Viral/diagnóstico , Prevalencia , Dominios y Motivos de Interacción de Proteínas , SARS-CoV-2 , Estudios Seroepidemiológicos , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/inmunología , Adulto JovenRESUMEN
The coronavirus disease 2019 (COVID-19) that is wreaking havoc on worldwide public health and economies has heightened awareness about the lack of effective antiviral treatments for human coronaviruses (CoVs). Many current antivirals, notably nucleoside analogs (NAs), exert their effect by incorporation into viral genomes and subsequent disruption of viral replication and fidelity. The development of anti-CoV drugs has long been hindered by the capacity of CoVs to proofread and remove mismatched nucleotides during genome replication and transcription. Here, we review the molecular basis of the CoV proofreading complex and evaluate its potential as a drug target. We also consider existing nucleoside analogs and novel genomic techniques as potential anti-CoV therapeutics that could be used individually or in combination to target the proofreading mechanism.
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Antivirales/uso terapéutico , Betacoronavirus/efectos de los fármacos , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/epidemiología , Genoma Viral , Pandemias , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/epidemiología , ARN Viral/genética , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/química , Adenosina Monofosfato/uso terapéutico , Alanina/análogos & derivados , Alanina/química , Alanina/uso terapéutico , Amidas/química , Amidas/uso terapéutico , Antivirales/química , Betacoronavirus/genética , Betacoronavirus/patogenicidad , COVID-19 , Infecciones por Coronavirus/virología , Citidina/análogos & derivados , Humanos , Hidroxilaminas , Terapia Molecular Dirigida/métodos , Mutación , Neumonía Viral/virología , Pirazinas/química , Pirazinas/uso terapéutico , ARN Viral/antagonistas & inhibidores , ARN Viral/metabolismo , Ribonucleósidos/química , Ribonucleósidos/uso terapéutico , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Transcripción Genética , Proteínas no Estructurales Virales/antagonistas & inhibidores , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , Replicación Viral/efectos de los fármacosRESUMEN
Patients with hypertension, diabetes, coronary heart disease, cerebrovascular illness, chronic obstructive pulmonary disease, and kidney dysfunction have worse clinical outcomes when infected with SARS-CoV-2, for unknown reasons. The purpose of this review is to summarize the evidence for the existence of elevated plasmin(ogen) in COVID-19 patients with these comorbid conditions. Plasmin, and other proteases, may cleave a newly inserted furin site in the S protein of SARS-CoV-2, extracellularly, which increases its infectivity and virulence. Hyperfibrinolysis associated with plasmin leads to elevated D-dimer in severe patients. The plasmin(ogen) system may prove a promising therapeutic target for combating COVID-19.
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Infecciones por Coronavirus/sangre , Susceptibilidad a Enfermedades/sangre , Fibrinolisina/metabolismo , Interacciones Huésped-Patógeno/fisiología , Plasminógeno/metabolismo , Neumonía Viral/sangre , Betacoronavirus/metabolismo , Betacoronavirus/patogenicidad , COVID-19 , Comorbilidad , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/mortalidad , Infecciones por Coronavirus/fisiopatología , Humanos , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/mortalidad , Neumonía Viral/fisiopatología , Síndrome de Dificultad Respiratoria/sangre , Síndrome de Dificultad Respiratoria/fisiopatología , Síndrome de Dificultad Respiratoria/virología , Factores de Riesgo , SARS-CoV-2Asunto(s)
Angioedema/inmunología , Betacoronavirus/inmunología , Infecciones por Coronavirus/inmunología , Síndrome de Liberación de Citoquinas/inmunología , Citocinas/metabolismo , Neumonía Viral/inmunología , Angioedema/sangre , Angioedema/patología , Angioedema/virología , Enzima Convertidora de Angiotensina 2 , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Antivirales/uso terapéutico , Biomarcadores/sangre , COVID-19 , Prueba de COVID-19 , Técnicas de Laboratorio Clínico/métodos , Congresos como Asunto , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/epidemiología , Síndrome de Liberación de Citoquinas/sangre , Síndrome de Liberación de Citoquinas/virología , Citocinas/antagonistas & inhibidores , Citocinas/sangre , Citocinas/inmunología , Humanos , Internet , Sistema Calicreína-Quinina/efectos de los fármacos , Sistema Calicreína-Quinina/inmunología , Pandemias , Peptidil-Dipeptidasa A/metabolismo , Neumonía Viral/sangre , Neumonía Viral/diagnóstico , Neumonía Viral/epidemiología , Alveolos Pulmonares/inmunología , Alveolos Pulmonares/patología , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismo , Factores de Tiempo , Tiempo de Tratamiento , Tratamiento Farmacológico de COVID-19RESUMEN
Coronaviruses have caused three major epidemics since 2003, including the ongoing SARS-CoV-2 pandemic. In each case, the emergence of coronavirus in our species has been associated with zoonotic transmissions from animal reservoirs1,2, underscoring how prone such pathogens are to spill over and adapt to new species. Among the four recognized genera of the family Coronaviridae, human infections reported so far have been limited to alphacoronaviruses and betacoronaviruses3-5. Here we identify porcine deltacoronavirus strains in plasma samples of three Haitian children with acute undifferentiated febrile illness. Genomic and evolutionary analyses reveal that human infections were the result of at least two independent zoonoses of distinct viral lineages that acquired the same mutational signature in the genes encoding Nsp15 and the spike glycoprotein. In particular, structural analysis predicts that one of the changes in the spike S1 subunit, which contains the receptor-binding domain, may affect the flexibility of the protein and its binding to the host cell receptor. Our findings highlight the potential for evolutionary change and adaptation leading to human infections by coronaviruses outside of the previously recognized human-associated coronavirus groups, particularly in settings where there may be close human-animal contact.
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Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Deltacoronavirus/aislamiento & purificación , Porcinos/virología , Zoonosis Virales/epidemiología , Zoonosis Virales/virología , Secuencia de Aminoácidos , Animales , Teorema de Bayes , Niño , Chlorocebus aethiops , Secuencia Conservada , Infecciones por Coronavirus/sangre , Deltacoronavirus/clasificación , Deltacoronavirus/genética , Deltacoronavirus/patogenicidad , Femenino , Haití/epidemiología , Humanos , Masculino , Modelos Moleculares , Mutación , Filogenia , Células Vero , Zoonosis Virales/sangreRESUMEN
The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) not only caused the COVID-19 pandemic but also had a major impact on farmed mink production in several European countries. In Denmark, the entire population of farmed mink (over 15 million animals) was culled in late 2020. During the period of June to November 2020, mink on 290 farms (out of about 1100 in the country) were shown to be infected with SARS-CoV-2. Genome sequencing identified changes in the virus within the mink and it is estimated that about 4000 people in Denmark became infected with these mink virus variants. However, the routes of transmission of the virus to, and from, the mink have been unclear. Phylogenetic analysis revealed the generation of multiple clusters of the virus within the mink. Detailed analysis of changes in the virus during replication in mink and, in parallel, in the human population in Denmark, during the same time period, has been performed here. The majority of cases in mink involved variants with the Y453F substitution and the H69/V70 deletion within the Spike (S) protein; these changes emerged early in the outbreak. However, further introductions of the virus, by variants lacking these changes, from the human population into mink also occurred. Based on phylogenetic analysis of viral genome data, we estimate, using a conservative approach, that about 17 separate examples of mink to human transmission occurred in Denmark but up to 59 such events (90% credible interval: (39-77)) were identified using parsimony to count cross-species jumps on transmission trees inferred using Bayesian methods. Using the latter approach, 136 jumps (90% credible interval: (117-164)) from humans to mink were found, which may underlie the farm-to-farm spread. Thus, transmission of SARS-CoV-2 from humans to mink, mink to mink, from mink to humans and between humans were all observed.
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COVID-19 , Visón , Filogenia , SARS-CoV-2 , Visón/virología , COVID-19/transmisión , COVID-19/virología , COVID-19/epidemiología , COVID-19/veterinaria , SARS-CoV-2/genética , Animales , Dinamarca/epidemiología , Humanos , Pandemias , Granjas , Betacoronavirus/genética , Betacoronavirus/clasificación , Genoma Viral , Infecciones por Coronavirus/veterinaria , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Infecciones por Coronavirus/transmisión , Glicoproteína de la Espiga del Coronavirus/genéticaRESUMEN
As countries in the world review interventions for containing the pandemic of coronavirus disease 2019 (COVID-19), important lessons can be drawn from the study of the full transmission dynamics of its causative agent-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)- in Wuhan (China), where vigorous non-pharmaceutical interventions have suppressed the local outbreak of this disease1. Here we use a modelling approach to reconstruct the full-spectrum dynamics of COVID-19 in Wuhan between 1 January and 8 March 2020 across 5 periods defined by events and interventions, on the basis of 32,583 laboratory-confirmed cases1. Accounting for presymptomatic infectiousness2, time-varying ascertainment rates, transmission rates and population movements3, we identify two key features of the outbreak: high covertness and high transmissibility. We estimate 87% (lower bound, 53%) of the infections before 8 March 2020 were unascertained (potentially including asymptomatic and mildly symptomatic individuals); and a basic reproduction number (R0) of 3.54 (95% credible interval 3.40-3.67) in the early outbreak, much higher than that of severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS)4,5. We observe that multipronged interventions had considerable positive effects on controlling the outbreak, decreasing the reproduction number to 0.28 (95% credible interval 0.23-0.33) and-by projection-reducing the total infections in Wuhan by 96.0% as of 8 March 2020. We also explore the probability of resurgence following the lifting of all interventions after 14 consecutive days of no ascertained infections; we estimate this probability at 0.32 and 0.06 on the basis of models with 87% and 53% unascertained cases, respectively-highlighting the risk posed by substantial covert infections when changing control measures. These results have important implications when considering strategies of continuing surveillance and interventions to eventually contain outbreaks of COVID-19.
Asunto(s)
Infecciones por Coronavirus/transmisión , Modelos Biológicos , Neumonía Viral/transmisión , COVID-19 , China/epidemiología , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/prevención & control , Monitoreo Epidemiológico , Femenino , Humanos , Masculino , Pandemias/prevención & control , Neumonía Viral/epidemiología , Neumonía Viral/prevención & control , Reproducibilidad de los Resultados , Procesos EstocásticosRESUMEN
Following the detection of the new coronavirus1 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its spread outside of China, Europe has experienced large epidemics of coronavirus disease 2019 (COVID-19). In response, many European countries have implemented non-pharmaceutical interventions, such as the closure of schools and national lockdowns. Here we study the effect of major interventions across 11 European countries for the period from the start of the COVID-19 epidemics in February 2020 until 4 May 2020, when lockdowns started to be lifted. Our model calculates backwards from observed deaths to estimate transmission that occurred several weeks previously, allowing for the time lag between infection and death. We use partial pooling of information between countries, with both individual and shared effects on the time-varying reproduction number (Rt). Pooling allows for more information to be used, helps to overcome idiosyncrasies in the data and enables more-timely estimates. Our model relies on fixed estimates of some epidemiological parameters (such as the infection fatality rate), does not include importation or subnational variation and assumes that changes in Rt are an immediate response to interventions rather than gradual changes in behaviour. Amidst the ongoing pandemic, we rely on death data that are incomplete, show systematic biases in reporting and are subject to future consolidation. We estimate that-for all of the countries we consider here-current interventions have been sufficient to drive Rt below 1 (probability Rt < 1.0 is greater than 99%) and achieve control of the epidemic. We estimate that across all 11 countries combined, between 12 and 15 million individuals were infected with SARS-CoV-2 up to 4 May 2020, representing between 3.2% and 4.0% of the population. Our results show that major non-pharmaceutical interventions-and lockdowns in particular-have had a large effect on reducing transmission. Continued intervention should be considered to keep transmission of SARS-CoV-2 under control.