Work

Climatic Influence on COVID‐19: Investigating the Role of Temperature and Humidity in the Spread of the Omicron Variant

Year: 2026

Type: article

Abstract: Understanding how climate modulates infectious disease dynamics is critical for anticipating epidemic patterns. After a hot debate on potential facilitation of population spread by climate factors during the first 2 years of the COVID‐19 pandemics, not much attention has been devoted to assess whether the ensuing SARS‐CoV‐2 waves also displayed similar climatic facilitation, or conversely, whether immunity dismissed any such forcing and potential signatures. This study examines the association between climatological variables—specifically temperature and absolute humidity (AH)—and the global incidence of the SARS‐CoV‐2 Omicron variant (B.1.1.529) during its massive epidemic wave (2021–2022). Using global‐scale epidemiological and climate data, we applied the scale‐dependent correlation analysis to identify transient, scale‐specific non‐linear associations between factors and the disease across regions. We found consistent significant local negative correlations between incidence and both temperature ( to ) and AH ( to ), particularly in mid‐latitudes during colder months. Threshold analyses revealed temperature and humidity ranges of 12°C–21°C and 8–12 g , respectively, where transmission was most favored, fully in line with previous results obtained for the first COVID‐19 variants. A stochastic population‐based model incorporating a temperature‐modulated infection rate reproduced epidemic dynamics more accurately than constant or seasonal formulations, reducing normalized residuals by approximately 40%–50%. These results largely demonstrate a robust climatic influence also on Omicron transmission yet underscoring the value of integrating environmental drivers into epidemic modeling and early‐warning frameworks.

Source: GeoHealth

DOI: 10.1029/2025gh001750

Authors: Leonardo López, Alejandro Fontal, Brandon Alfaro, Xavier Rodó

Institutions: Barcelona Institute for Global Health, Universitat de Barcelona, Institució Catalana de Recerca i Estudis Avançats

Language: English

Topic: COVID-19 epidemiological studies

Subfield: Modeling and Simulation

Field: Mathematics

Domain: Physical Sciences

SDGs: Good health and well-being, Climate action

Open Access status: gold

Estimated APC paid: $3,000