ArticleProceedings of the National Academy of Sciences of the United States of America2009
Absolute humidity modulates influenza survival, transmission, and seasonality.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT05264948 (The Effect of Seasonal Factors on the Virulence and Mortality of COVID 19), which is not on this map. Cited by 517 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.
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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.
The Effect of Seasonal Factors on the Virulence and Mortality of COVID 19
Who cites it
517 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Effects of ambient temperature on influenza-like illness: A multicity analysis in Shandong Province, China, 2014-2017.Frontiers in public health · 2022Pooled it
- Resurgence of large-scale influenza A (H1N1) outbreaks: Modeling the interplay of transmission, loss of immunity, and vaccination.Infectious Disease Modelling · 2027Article
- Sensitivity of Convergent Cross Mapping to temporal discontinuities: A case study of seasonal influenza in Hong Kong.Infectious Disease Modelling · 2026Article
- Associations between El Niño-Southern Oscillation (ENSO) and tuberculosis incidence in China: a nationwide study.One health (Amsterdam, Netherlands) · 2026Article
- The limitations of non-mechanistic methods for characterizing pathogen-pathogen interactions: A simulation study.PLoS computational biology · 2026Article
- Physics-guided framework for climate dependent disease prediction: coupling compartment model with deep learning.BMC public health · 2026Article
- Unified climate factors predict influenza outbreak seasonality across tropical and temperate regions.PNAS nexus · 2026Article
- Climate change and infectious diseases.Nature medicine · 2026Review
- Noisy periodicity in tropical respiratory disease dynamics.medRxiv : the preprint server for health sciences · 2026Article
- Spatiotemporal patterns of climate-sensitive vector-borne diseases in Bangladesh: leveraging machine learning and spatial regression for intervention strategies.BMC medicine · 2026Article
- XIS-humidity: a daily spatiotemporal machine-learning model for dew point in the contiguous United States.Environmental research communications · 2026Article
- Understanding spatiotemporal clustering of seasonal influenza in the United States.BMC infectious diseases · 2026Article
- Article
- SpecFlu-Net: A frequency-aware neural architecture with temporal-dependency optimization for long-term seasonal influenza transmission forecasting.Infectious medicine · 2026Article
- Modeling the dynamics of seasonal influenza in response to meteorological conditions and antigenic variation: a simulation study.BMC public health · 2026Article
- Reconstructing the early spatial spread of pandemic respiratory viruses in the United States.Proceedings of the National Academy of Sciences of the United States of America · 2026Article
- Forecasting Influenza Epidemics and Pandemics in the Age of AI and Machine Learning.Reviews in medical virology · 2026Review
- Modeling spatially dependent count time series data using COM-poisson INGARCH Models.PloS one · 2026Article
- Influenza A/H3N2 epidemiology in England during the 2025 to 2026 season: a mathematical modelling study.Communications health · 2026Article
- Influenza Surveillance in the Central African Republic From 2015 to 2018 to Inform Vaccination and Treatment Strategies.Influenza and other respiratory viruses · 2026Article
457 more citing papers are in PubMed but not listed here.
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2 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Influenza A incidence peaks during winter in temperate regions. The basis for this pronounced seasonality is not understood, nor is it well documented how influenza A transmission principally occurs. Previous studies indicate that relative humidity (RH) affects both influenza virus transmission (IVT) and influenza virus survival (IVS). Here, we reanalyze these data to explore the effects of absolute humidity on IVT and IVS. We find that absolute humidity (AH) constrains both transmission efficiency and IVS much more significantly than RH. In the studies presented, 50% of IVT variability and 90% of IVS variability are explained by AH, whereas, respectively, only 12% and 36% are explained by RH. In temperate regions, both outdoor and indoor AH possess a strong seasonal cycle that minimizes in winter. This seasonal cycle is consistent with a wintertime increase in IVS and IVT and may explain the seasonality of influenza. Thus, differences in AH provide a single, coherent, more physically sound explanation for the observed variability of IVS, IVT and influenza seasonality in temperate regions. This hypothesis can be further tested through future, additional laboratory, epidemiological and modeling studies.
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