Excess mortality during the COVID-19 pandemic, a narrative review

Capturing all the deaths caused by COVID-19 through epidemiologic surveillance based on individual case notification is difficult, therefore, all-cause excess mortality (EM) is an appropriate measure for geographic comparisons and monitoring of the application of non-pharmacological sanitary measures. This is a narrative review of the literature about the observed EM during the COVID-19 pandemic. A research was made on scientific databases (Google Scholar, Pubmed, Virtual Health Library) using the terms "excess mortality", "excess deaths", "COVID-19", "coronavirus", "SARS-CoV-2". It included publications between 2019 and June 16, 2020. Twenty-seven articles were selected from 116 publications found. Most of them correspond to original articles with an analytical ecological study design. They confirm EM in the locations studied, with higher proportion of men and older people and with remarkable spatial heterogeneity. The need to optimize the standardization and updating of mortality registration and reporting mechanisms is highlighted. At a local level, data about EM that will allow these analyses is incipiently becoming available.