ArticleAging2021
Centenarians exposed to the Spanish flu in their early life better survived to COVID-19.
Article in Aging, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 16 papers, 1 of them a synthesis that pooled it.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
16 citing papers in PubMed, 1 synthesis or guideline pooled it, 25 citations in OpenAlex.
- Pooled it
- Why Some People Live Past 100: The Role of the Immune System in Centenarians, Semi-Supercentenarians and Supercentenarians.International journal of molecular sciences · 2026Review
- The long-lived immune system of centenarians.Nature reviews. Immunology · 2026Review
- Centenarian Mortality Rate During COVID-19: Protocol for a Systematic Review and Meta-Analysis.JMIR research protocols · 2025Article
- Mortality Trends in Pre-COVID-19 and COVID-19 Eras Among Oldest Veterans.The journals of gerontology. Series A, Biological sciences and medical sciences · 2025Article
- Phylogenetic and epidemiological insights into centenarians' resilience to COVID-19: exploring the role of past coronavirus pandemics.Frontiers in microbiology · 2025Article
- Article
- Centenarians, semi and supercentenarians, COVID-19 and Spanish flu: a serological assessment to gain insight into the resilience of older centenarians to COVID-19.Immunity & ageing : I & A · 2024Article
- Sicilian semi- and supercentenarians: identification of age-related T-cell immunophenotype to define longevity trait.Clinical and experimental immunology · 2023Article
- The Phenotypic Characterization of the Oldest Italian Man from December 28, 2020, to September 23, 2021, A.T., Strengthens the Idea That the Immune System can Play a Key Role in the Attainment of Extreme Longevity.Journal of clinical medicine · 2023Article
- Role of Sex and Age in Fatal Outcomes of COVID-19: Women and Older Centenarians Are More Resilient.International journal of molecular sciences · 2023Review
- Sex and gender affect immune aging.Frontiers in aging · 2023Review
- Centenarians born before 1919 are resistant to COVID-19.Aging clinical and experimental research · 2023Article
- Randomization, design and analysis for interdependency in aging research: no person or mouse is an island.Nature aging · 2022Article
- The oldest unvaccinated Covid-19 survivors in South America.Immunity & ageing : I & A · 2022Article
- MUC22, HLA-A, and HLA-DOB variants and COVID-19 in resilient super-agers from Brazil.Frontiers in immunology · 2022Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
3 authors at 2 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundAlthough it is known that mortality due to COVID-19 increases progressively with age, the probability of dying from this serious infection among the oldest-old population is little known, and controversial data are found in literature.
methodsWe examine the mortality by year and month of birth of Belgians who had turned 100 during the current COVID-19 pandemic and whose birth fell on the years around the end the First World War and the outbreak of the H1N1 "Spanish flu" pandemic.
findingsThe COVID-19 mortality of the "older" centenarians is significantly lower than that of "younger" centenarians, and this difference between the two groups reaches a maximum on August 1, 1918 as the discriminating cut-off date of birth. Having excluded the plausible impact of the end of WWI it becomes clear that this date corresponds to the time of reporting the first victims of the Spanish flu pandemic in Belgium.
interpretationIn this study, the striking temporal coincidence between the outbreak of the Spanish flu epidemic and the birth of the cohorts characterized by greater fragility towards COVID-19 in 2020 strongly suggests a link between exposure to 1918 H1N1 pandemic influenza and resistance towards 2020 SARS-Cov-2. It can be speculated that the lifetime persistence of cross-reactive immune mechanisms has enabled centenarians exposed to the Spanish flu to overcome the threat of COVID-19 a century later.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.