Do I have your attention? Interesting concept- does pollen have anything to do with COVID?
Allergy Partners, as a country wide organization of allergists, just started having a Journal Club. I had the honor to being the first presenter of a few articles.
One of the articles dealt with pollen and COVID-19.
The article- “Higher airborne pollen concentrations correlated with increased SARS-CoV-2 infection rates, as evidenced from 31 countries across the globe’’ appeared in the Proceedings of the National Academy of Science 2021 Volume 118 (#12) e2019034118. The lead author was Damialis and one of the authors, Dr. Leonard Bielory has helped me with pollen counting over the years.
This article did not conclude that COVID is carried on pollen!! They were very careful and emphasized this point. There was to be NO MISUNDERSTANDING or a lead to PANIC. It is a very interesting correlation- not causation.
This was a very complicated article replete with a published supplement. My preparatory material for the discussion was 50 pages for this 10 page article. Also, it is an article that you need to look at in color to make sense of the data. I was introduced to many new words; inflammasome, bag plot, heat map, exposome, ridge regression, and anomaly detection.
Purpose – to look at the relationship between daily pollen concentrations and COVID infection rates along with meteorologic and sociodemographic data.
Methods – 31 countries, 80 regions, 5 continents and 248 pollen counting stations. Wikipedia reports on lockdowns, and weather reports.
Why- after the global pandemic was declared on March 12, 2020 there was a warm spell in the northern hemisphere with the first seasonal peak of tree pollen. Tree pollen was elevated along with COVID infection rates.
Interesting background- COVID is from the betacoronaviridae family, has zoonotic origins and is very susceptible to interferon (how our immune system reacts in part). It has evolved ways of dealing with our interferon.
Pollen releases an ‘unknown’ substance that down-regulates our antiviral interferon. Pollen then can make us more susceptible to viral infections. Could pollen then make it easier for viral infections to take hold?
Results – There were many interesting statistical applications to the data and to the models established.
- The onset of the exponential phase of COVID infection (rapid increase in cases) was related to pollen counts.
- Higher rates of infection were seen in areas of high population density and high pollen counts.
- Lockdowns had a significant impact on infection rates accounting for a 50% reduction.
- Pollen is a modulating factor adding 10-30% to the infection rate.
- NO EVIDENCE THAT POLLEN GRAINS CARRY THE VIRUS
- Contact is required to acquire infection.
- Pollen grains act at the very site of viral entry, the nose, and help the virus by down-regulating interferon.
- This pollen effect is observed in everyone.
- Recommended wearing a particle filter mask during high pollen seasons.
This was a tough article to review but had fascinating and thought-provoking concepts.