The Proceedings of the National Academy of Sciences of the United States of America published the study Higher airborne pollen concentrations correlated with increased SARS-CoV-2 infection rates, as evidenced from 31 countries across the globe.
The research showed that airborne pollen on average accounts for 44% of the variation in infection rates in addition to humidity and air temperature.
Pollen exposure weakens the immunity by diminishing the antiviral interferon response.
“Our large-scale retrospective data analysis based on 80 individual time series from 130 regions in 31 countries in all inhabited continents across the globe (8,019 data points) enabled us to reveal a robust and significant positive correlation between SARS-CoV-2 infection rates and airborne pollen concentrations, which was halved under lockdown.”