International study concludes that pollen exposure may increase risk of coronavirus infection

An international study has concluded that the level of pollen in the atmosphere is an important risk factor for COVID-19. This research, which was conducted in 31 countries on five continents, has recently been published in the scientific journal Proceedings of the National Academy of Sciences (PNAS).

For this work, air pollen data from 130 stations were analyzed and correlated with SARS-CoV-2 infection, meteorological factors and other variables such as population density. Pollen content explains 44% of the observed variability in infection rates.

Among the more than 150 researchers who contributed to this work are Arturo H. Ariño, Mónica González, Estrella Robles and Anabel Pérez de Zabalza, scientists from the Faculty of Sciences of the University of Navarra.

Pollen measurements in Pamplona, Tudela and Santesteban
These researchers from the University of Navarra have carried out pollen monitoring during the last two years, collecting weekly samples at the Clínica Universidad de Navarra, the Hospital Reina Sofía de Tudela and the Doneztebe/Santesteban Health Center, in collaboration with the Allergology Service of the Navarra Hospital Complex. These measurements have been carried out on behalf of the Institute of Public and Labor Health of Navarra (ISPLN) for the LIFE NAdapta project, a European project that aims to develop adaptation measures against Climate Change, whose health contents are coordinated by the ISPLN. 

"At the University we classify pollen, we calculate how many grains there are per cubic meter of air each day, and with these data and others such as climatological, ecological or epidemiological data we prepare a weekly forecast that the Government of Navarra and the City Councils distribute to the public," says Arturo Ariño, a researcher at the Institute of Biodiversity and Environment of the University of Navarra.

One of the recommendations of the international study is the use of particle filter masks for spring in those people who are at high risk, such as allergy sufferers. In this sense, Arturo Ariño assures that most of the hygienic masks, if used properly, can reduce the exposure to pollen and therefore minimize allergic symptoms and limit COVID-19 infection.

" Pollen is always in the air, at different concentrations depending on the site, the day or the time of year. You can't completely avoid exposure, although you can greatly reduce it indoors through filters and particle traps, and generally keeping the environmentclean."

Bibliographic reference.

Athanasios Damialis, et al. Higher airborne pollen concentrations correlated with increased SARS-CoV-2 infection rates, as evidenced from 31 countries across the globe. Proceedings of the National Academy of Sciences Mar 2021, 118 (12), pp.1-10. DOI: 10.1073/pnas.2019034118.