Unveiling a Recurring Pattern in International Influenza Epidemics
In a groundbreaking study published in the early online edition of the Proceedings of the National Academy of Sciences on Oct. 31, researchers at the University of California San Diego have found that humidity and temperature play a crucial role in the spread of influenza across global regions.
The study, led by Scripps postdoctoral researcher Ethan Deyle, used the empirical dynamic modeling (EDM) approach developed by Scripps ecologist George Sugihara and colleagues. The EDM framework, initially designed for ecological forecasting and identifying causal drivers, was applied to flu outbreak patterns for the first time.
The study analysed nearly 20 years of global influenza data from the World Health Organization's Global Health Atlas. The findings offer a unifying synthesis that explains flu outbreaks with a single model that applies equally to the tropics and temperate regions.
The study found a positive association between flu outbreaks, absolute humidity (amount of moisture in the air), and temperature across all latitudes. The critical temperature window for this association is 70-75 degrees Fahrenheit (21-24 degrees Celsius). Humidity levels above and below this window become a key factor in the spread of the flu virus.
The researchers suggest that public health initiatives such as placing humidifiers in schools and hospitals during cold, dry, temperate winters and in the tropics, perhaps using dehumidifiers or air conditioners set above 75° F to dry air in public buildings, could be set based on these findings.
The study's findings challenge the common belief that flu outbreaks are solely linked to seasonal temperature changes. Deyle stated that the paper provides an important missing link and hopes it will spur further investigation and the implementation of public health interventions addressing the role dry air plays in flu outbreaks in countries with temperate climates.
Previous research, including work by UC San Diego and similar institutes, has established that low humidity reduces the inactivation rate of influenza virus particles in aerosols, increasing airborne transmission. Lower temperatures also stabilize the virus and promote longer survival times outside the host. These environmental factors create seasonal patterns of influenza outbreaks, with temperate regions experiencing winter peaks and tropical regions exhibiting variable patterns often linked to rainy seasons or temperature drops.
In conclusion, this UC San Diego study provides valuable insights into the role of humidity and temperature in influenza transmission. By understanding these factors, public health initiatives can be designed to mitigate the spread of the flu virus, potentially saving lives and reducing the impact of flu outbreaks worldwide.
[1] Deyle, E., et al. (2022). Humidity and temperature significantly mediate the spread of influenza across global regions. Proceedings of the National Academy of Sciences.
[4] Xiao, Y., et al. (2010). Humidity and temperature effects on influenza A virus survival in aerosols. Journal of Virological Methods, 176(1), 12-18.
Read also:
- Inadequate supply of accessible housing overlooks London's disabled community
- Strange discovery in EU: Rabbits found with unusual appendages resembling tentacles on their heads
- Duration of a Travelling Blood Clot: Time Scale Explained
- Fainting versus Seizures: Overlaps, Distinctions, and Proper Responses
