Abstract
Background: Understanding the dynamics of the COVID-19 pandemic and evaluating the efficacy of control measures requires knowledge of the number of infections over time. This number, however, often differs from the number of confirmed cases because of a large fraction of asymptomatic infections and different testing strategies.
Methods: This study uses death count statistics, age-dependent infection fatality risks, and stochastic modeling to estimate the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections among adults (aged 20 years or older) in 165 countries over time, from early 2020 until June 25, 2021. The accuracy of the approach is confirmed through comparison with previous nationwide seroprevalence surveys.
Results: The estimates presented reveal that the fraction of infections that are detected vary widely over time and between countries, and hence confirmed cases alone often yield a false picture of the pandemic. As of June 25, 2021, the nationwide cumulative fraction of SARS-CoV-2 infections (cumulative infections relative to population size) was estimated as 98% (95% confidence interval [CI] 93-100%) for Peru, 83% (95% CI 61-94%) for Brazil, and 36% (95% CI 23-61%) for the United States.
Conclusions: The time-resolved estimates presented expand the possibilities to study the factors that influenced and still influence the pandemic’s progression in 165 countries.
Keywords: COVID-19; Exponential growth rate; Infection fatality risk; Prevalence; SARS-CoV-2; Time series.
【저자키워드】 COVID-19, SARS-CoV-2, Prevalence, Time series, Exponential growth rate, Infection fatality risk, 【초록키워드】 Brazil, Efficacy, coronavirus, pandemic, knowledge, SARS-COV-2 infection, COVID-19 pandemic, Infection, progression, severe acute respiratory syndrome Coronavirus, asymptomatic infections, Accuracy, asymptomatic infection, death, understanding, United States, estimate, SARS-CoV-2 infections, fatality, Population size, Exponential growth rate, exponential growth, growth rate, confirmed case, acute respiratory syndrome, Older, Factor, 95% CI, acute respiratory syndrome coronavirus, acute respiratory syndrome coronavirus 2, 95% confidence interval, confirmed cases, measure, fraction, cumulative, The United States, approach, time, country, expand, 【제목키워드】 SARS-COV-2 infection, country,