Epidemiology

  • Article
    | Open Access

    Here, the authors determine seroprevalence of antibodies to SARS-CoV-2 in healthy blood donors in the cities of Wuhan, Shenzhen, and Shijiazhuang in China between January and April 2020. The age- and sex-standardized SARS-CoV-2 seroprevalence among 18–60 year-old adults is, with 2.66%, the highest in Wuhan.

    • Le Chang
    • , Wangheng Hou
    •  & Lunan Wang
  • Article
    | Open Access

    One of the primary tools that researchers use to predict risk is the case-control study. Here, the authors identify a flaw, temporal bias, that is specific to and uniquely associated with these studies that occurs when the study period is not representative of the data that clinicians have during the diagnostic process, undermining the validity of predictions.

    • William Yuan
    • , Brett K. Beaulieu-Jones
    •  & Isaac S. Kohane
  • Article
    | Open Access

    Social distancing policies aiming to reduce COVID-19 transmission have been reflected in reductions in human mobility. Here, the authors show that reduced mobility is correlated with decreased transmission, but that this relationship weakened over time as social distancing measures were relaxed.

    • Pierre Nouvellet
    • , Sangeeta Bhatia
    •  & Christl A. Donnelly
  • Article
    | Open Access

    The role of children in the spread of COVID-19 is not fully understood, and the circumstances under which schools should be opened are therefore debated. Here, the authors demonstrate protocols by which schools in France can be safely opened without overwhelming the healthcare system.

    • Laura Di Domenico
    • , Giulia Pullano
    •  & Vittoria Colizza
  • Article
    | Open Access

    New Zealand has been relatively successful in controlling COVID-19 due to implementation of strict non-pharmaceutical interventions. Here, the authors demonstrate a striking decline in reports of influenza and other non-influenza respiratory pathogens over winter months in which the interventions have been in place.

    • Q. Sue Huang
    • , Tim Wood
    •  & Richard J. Webby
  • Article
    | Open Access

    Dexamethasone has been shown to have survival benefits for critically ill patients hospitalised with COVID-19 in the UK. Here, the authors estimated the number of lives that could be saved through a UK and global roll out of the drug and demonstrate that it is a cost-effective option.

    • Ricardo Águas
    • , Adam Mahdi
    •  & Mesulame Namedre
  • Article
    | Open Access

    Asymptomatic malaria infections contribute to transmission. Here, Sumner et al. infer participant-to-mosquito transmission by sampling naturally-fed mosquitoes from households in Western Kenya and find that asymptomatic infections more than double the odds of transmission to a mosquito compared to symptomatic infections.

    • Kelsey M. Sumner
    • , Elizabeth Freedman
    •  & Steve M. Taylor
  • Article
    | Open Access

    REACT-2 is a large-scale community study of SARS-CoV-2 seroprevalence in England. Here, the authors estimate that 6% of adults in England had been infected by mid-July 2020, with health and long-term care workers and those of Black or South Asian ethnicity disproportionately affected.

    • Helen Ward
    • , Christina Atchison
    •  & Paul Elliott
  • Article
    | Open Access

    Understanding if lasting immune responses can be induced by SARS-CoV-2 infection is important for controlling the COVID-19 pandemic. Here, the authors show, in a cohort of 25 patients, that IgG and T cell responses, as well as neutralising antibody, are still detectable against various SARS-CoV-2 proteins 3 months post-symptom onset, while IgM levels largely wane at this time.

    • Xiao-Lin Jiang
    • , Guo-Lin Wang
    •  & Mai-Juan Ma
  • Article
    | Open Access

    Spread of SARS-CoV-2 in the early phase of the pandemic has been driven by high population susceptibility, but virus sensitivity to climate may play a role in future outbreaks. Here, the authors simulate SARS-CoV-2 dynamics in winter assuming climate dependence is similar to an endemic coronavirus strain.

    • Rachel E. Baker
    • , Wenchang Yang
    •  & Bryan T. Grenfell
  • Article
    | Open Access

    Establishing the natural history of COVID-19 requires longitudinal data from population-based cohorts. Here, the authors use linked primary care, testing, and hospital data to describe the disease in ~100,000 individuals with a COVID-19 diagnosis among a population of ~5.5 million in Catalonia, Spain.

    • Edward Burn
    • , Cristian Tebé
    •  & Talita Duarte-Salles
  • Article
    | Open Access

    Incidence of COVID-19 has been high in parts of South America including Brazil, and information on effective intervention strategies is needed. Here, the authors use mathematical modelling to show that reductions in social distancing should be made gradually to avoid a severe second peak of cases.

    • Osmar Pinto Neto
    • , Deanna M. Kennedy
    •  & Renato Amaro Zângaro
  • Article
    | Open Access

    Test, trace, and isolate programmes are central to COVID-19 control. Here, Viola Priesemann and colleagues evaluate how to allocate scarce resources to keep numbers low, and find that if case numbers exceed test, trace and isolate capacity, there will be a self-accelerating spread.

    • Sebastian Contreras
    • , Jonas Dehning
    •  & Viola Priesemann
  • Article
    | Open Access

    The growing need for realism in addressing complex public health questions calls for accurate models of the human contact patterns that govern disease transmission. Here, the authors generate effective population-level contact matrices by using highly detailed macro (census) and micro (survey) data on key socio-demographic features.

    • Dina Mistry
    • , Maria Litvinova
    •  & Alessandro Vespignani
  • Article
    | Open Access

    Sparse testing early in the SARS-CoV-2 pandemic hinders estimation of the dates and origins of initial case importations. Here, the authors show that the main source of cases imported from China shifted from Wuhan to other Chinese cities by mid-February, especially for African locations.

    • Tigist F. Menkir
    • , Taylor Chin
    •  & Rene Niehus
  • Article
    | Open Access

    Low-resource settings can face additional challenges in managing the COVID-19 pandemic. Here, the authors use mathematical modelling to investigate transmission in the state of Bahia, Brazil, and quantify control measures needed to prevent the hospital system becoming overwhelmed.

    • Juliane F. Oliveira
    • , Daniel C. P. Jorge
    •  & Roberto F. S. Andrade
  • Article
    | Open Access

    Contact tracing is critical to controlling COVID-19, but most protocols only “forward-trace” to notify people who were recently exposed. Using a stochastic branching-process model, the authors show that “bidirectional” tracing to identify infector individuals and their other infectees robustly improves outbreak control.

    • William J. Bradshaw
    • , Ethan C. Alley
    •  & Kevin M. Esvelt
  • Article
    | Open Access

    Anecdotal reports suggest potential severity and outcome differences between sexes following infection by SARS-CoV-2. Here, the authors perform meta-analyses of more than 3 million cases collected from global public data to demonstrate that male patients with COVID-19 are 3 times more likely to require intensive care, and have ~40% higher death rate.

    • Hannah Peckham
    • , Nina M. de Gruijter
    •  & Claire T. Deakin
  • Article
    | Open Access

    Although many COVID-19 cases are mild, most information about symptoms is derived from hospitalized patients. Here, the authors link self-reported symptom surveys to primary care data to describe the longitudinal dynamics of COVID-19 in non-hospitalized individuals.

    • Barak Mizrahi
    • , Smadar Shilo
    •  & Eran Segal
  • Article
    | Open Access

    High numbers of COVID-19-related deaths have been reported in the United States, but estimation of the true numbers of infections is challenging. Here, the authors estimate that on 1 June 2020, 3.7% of the US population was infected with SARS-CoV-2, and 0.01% was infectious, with wide variation by state.

    • H. Juliette T. Unwin
    • , Swapnil Mishra
    •  & Seth Flaxman
  • Article
    | Open Access

    Environmental and dietary factors are known to play a role in the development of coronary heart disease. Here the authors apply a genomic-inspired methodology to Nurses’ Health Study data to explore comprehensively and agnostically the association of 257 nutrients and 117 foods with coronary heart disease risk.

    • Soodabeh Milanlouei
    • , Giulia Menichetti
    •  & Albert-László Barabási
  • Article
    | Open Access

    In this study, the authors present a genomic surveillance of avian influenza genomes sampled from live poultry markets in China. They report that a number of variants have emerged since 2016 that pose an increased risk to humans. They highlight the importance of continuous genome surveillance of circulating influenza strains.

    • Yuhai Bi
    • , Juan Li
    •  & Weifeng Shi
  • Article
    | Open Access

    Despite its importance for the targeting of interventions, little is known about the degree to which cardiovascular risk factors cluster within different socio-geographic levels in South Asia. Here the authors report on a cross-sectional study identifying wide variations in the clustering between risk factors and socio-geographic levels in India.

    • Anne C. Bischops
    • , Jan-Walter De Neve
    •  & Pascal Geldsetzer
  • Article
    | Open Access

    Here the authors present a SARS-CoV2 seroepidemiological observational study from a random, household-based study population in a small town in Germany, showing the effect of a super-spreading event on infection rate, severity, and potentially infection fatality rate.

    • Hendrik Streeck
    • , Bianca Schulte
    •  & Gunther Hartmann
  • Article
    | Open Access

    Yellow fever is absent from the Asia/Pacific region, despite presence of the mosquito vector. Here, the authors demonstrate that mosquitoes collected from field sites across the region are capable of transmitting yellow fever virus, indicating that vector competence is not a barrier to disease spread.

    • Lucy de Guilhem de Lataillade
    • , Marie Vazeille
    •  & Pei-Shi Yen
  • Article
    | Open Access

    Recent evidence has suggested that blood type may be associated with severe COVID-19. Here, the authors use data from ~14,000 individuals tested for SARS-CoV-2 at a New York City hospital, and find that certain ABO and Rh blood types are associated with infection, intubation, and death.

    • Michael Zietz
    • , Jason Zucker
    •  & Nicholas P. Tatonetti
  • Article
    | Open Access

    The Netherlands is a country highly affected by the COVID-19 pandemic. In this study, Slot, Hogema and colleagues report a low SARS-CoV-2 seroprevalence one month into the outbreak and provide insights into virus exposure by region and age group when widespread non-pharmaceutical interventions are in place.

    • Ed Slot
    • , Boris M. Hogema
    •  & Hans L. Zaaijer
  • Article
    | Open Access

    Many published studies of the current SARS-CoV-2 pandemic have analysed data from non-representative samples from populations. Here, using UK BioBank samples, Gibran Hemani and colleagues discuss the potential for such studies to suffer from collider bias, and provide suggestions for optimising study design to account for this.

    • Gareth J. Griffith
    • , Tim T. Morris
    •  & Gibran Hemani
  • Article
    | Open Access

    There is ongoing debate about the effective combination of strategies for COIVD-19 control. Here, the authors use an agent-based model to quantify and compare several intervention strategies, and identify minimal levels of social distancing compliance required to control the epidemic in Australia.

    • Sheryl L. Chang
    • , Nathan Harding
    •  & Mikhail Prokopenko
  • Article
    | Open Access

    Diverse toxicological mechanisms may mediate the impact of environmental toxicants on pregnancy outcomes. In this study the authors introduce an analytical framework for multivariate mediation analysis to identify mediation pathways in the relationship between environmental toxicants and gestational age at delivery.

    • Max T. Aung
    • , Yanyi Song
    •  & Bhramar Mukherjee
  • Article
    | Open Access

    In this study, the authors present an analysis of 247 full-genome SARS-CoV-2 sequences obtained from two communities in Wisconsin, USA, and report distinct patterns of viral spread. Their results suggest that patterns of SARS-CoV-2 transmission and spread may vary substantially, even between neighbouring communities.

    • Gage K. Moreno
    • , Katarina M. Braun
    •  & Thomas C. Friedrich
  • Article
    | Open Access

    In this study, Adi Stern and colleagues use full genome sequences of SARS-CoV-2 to look at the rate of infections in Israel. They report that social distancing had a significant effect on minimising the rate of transmission, and find evidence for transmission heterogeneity (superspreading events).

    • Danielle Miller
    • , Michael A. Martin
    •  & Adi Stern
  • Article
    | Open Access

    Here the authors analyze disease burden and clinical severity of COVID-19 during the first wave in Wuhan, China in comparison to past influenza virus pandemics and COVID-19 in the US and Canada. These estimates of symptomatic cases, medical consultations, hospitalizations and deaths should guide preparedness for this disease.

    • Juan Yang
    • , Xinhua Chen
    •  & Prof Hongjie Yu
  • Article
    | Open Access

    Observationally, lower birthweight is a risk factor for cardiometabolic disease. Using Mendelian Randomization, the authors investigate whether maternal genetic factors that lower offspring birthweight also increase offspring cardiometabolic risk and show that the observational correlation is unlikely to be due to the intrauterine environment.

    • Gunn-Helen Moen
    • , Ben Brumpton
    •  & David M. Evans
  • Article
    | Open Access

    Since 1970, several cholera outbreaks caused by the “seventh pandemic” (7PET) lineage have been reported in Europe. Here, the authors demonstrate that the outbreaks were caused by repeated introductions of 7PET into Europe, rather than local environmental sources.

    • Mihaela Oprea
    • , Elisabeth Njamkepo
    •  & François-Xavier Weill
  • Article
    | Open Access

    There are a growing number of reports of neonatal SARS-CoV-2 infections. Here, De Luca and colleagues systematically analyse 176 published cases to better understand the route of transmission, as well as the clinical features and outcomes of neonatal COVID-19.

    • Roberto Raschetti
    • , Alexandre J. Vivanti
    •  & Daniele De Luca
  • Article
    | Open Access

    Healthcare workers may be at higher risk of SARS-CoV-2 infection than the general population. Here, the authors report 19% seroprevalence of SARS-CoV-2 antibodies among 2,149 employees in a Swedish hospital. Seroprevalence was associated with patient contact and higher than the seroprevalence in the community in same time period.

    • Ann-Sofie Rudberg
    • , Sebastian Havervall
    •  & Charlotte Thålin
  • Article
    | Open Access

    Although SARS-CoV-2 has spread rapidly, the contribution of super-spreading events to transmission is unclear. Here, the authors show that the number of secondary infections arising from an individual infection in the early phase of the outbreak was highly skewed, indicating that super-spreading events occurred.

    • Liang Wang
    • , Xavier Didelot
    •  & Yuhai Bi
  • Article
    | Open Access

    COVID-19-related travel restrictions were imposed in China around the same time as major annual holiday migrations, with unknown combined impacts on mobility patterns. Here, the authors show that restructuring of the travel network in response to restrictions was temporary, whilst holiday-related travel increased pressure on healthcare services with lower capacity.

    • Hamish Gibbs
    • , Yang Liu
    •  & Rosalind M. Eggo
  • Article
    | Open Access

    Detailed knowledge of the characteristics of COVID-19 patients helps with public health planning. Here, the authors use routinely-collected data from seven databases in three countries to describe the characteristics of >30,000 patients admitted with COVID-19 and compare them with those admitted for influenza in previous years.

    • Edward Burn
    • , Seng Chan You
    •  & Patrick Ryan
  • Article
    | Open Access

    Highly accurate antibody tests for SARS-CoV-2 are needed for surveillance in low-prevalence populations. Here, the authors find seroprevalence of less than 1% in two San Francisco Bay Area populations at the beginning of April, and that seroreactivity is generally predictive of in vitro neutralising activity.

    • Dianna L. Ng
    • , Gregory M. Goldgof
    •  & Charles Y. Chiu