The sunshine days are returning... and with them pollen, associated with a potential increase in the number of COVID-19 contaminations. Or in any case, this is the conclusion of a research paper published in the Proceedings of the National Academy of Sciences on March 9, 2021. According to researchers, exposure to these tiny grains of plant matter could increase your risk of developing the disease. And this may happen even if you do not suffer from any pollen allergy or other such hay fever.
Increased pollen, increased infections
A few years ago, these same scientists had already shown that pollen could 'suppress' the reaction of our immune system against viruses. And the reason for that is, its seeds interfere with the proteins responsible for signalling the presence of an intrusion to the cells that line the respiratory tract (antiviral interferons). Thus, they can make people more susceptible to this type of infection. This would be the case for the coronavirus.
In order to analyse this hypothesis, the researchers observed, in 31 countries, variations in new COVID-19 infections, those in pollen levels as well as weather conditions between January and April 2020. As it turns out, infection rates tended to add up four days after a strong pollen episode: they were on average 4% higher for each increase of 100 airborne grains per cubic meter.
Actions to protect yourself from it
People suffering from hay fever during as individuals this particular period were not susceptible to it, everyone would be affected by the phenomenon. The plant physiologist and co-author of the study Lewis Ziska, interviewed by ScienceAlert, thus advises to stay indoors and limit your exposure - both to coronavirus and to pollen, as you will understand - on days when ther are observations of spikes of grains in suspension.
During the 'pollen season' - which moreover arrives earlier and lasts longer and longer, due to climate change - wearing a mask outdoors will also benefit you, since most of the protections are more than sufficient for filter the pollen grains. Finally, be sure to stay alert to your symptoms: sneezing and coughing could signal a mild case of COVID-19, and not a simple allergy (and vice versa).