An international team of scientists has revealed that in the spring months, people can become especially susceptible to coronavirus infection. This is due to an increase in the concentration of pollen in the air, which can weaken the immune system, and does not depend on allergies. This is reported in an article published in the journal Proceedings of the National Academy of Sciences.
It is known that the effect of pollen on the body reduces the antiviral interferon response, making various infections more dangerous. Since SARS-CoV-2 is sensitive to interferons, the researchers decided to test whether pollen could affect people’s vulnerability to COVID-19. According to their hypothesis, the more pollen from flowering plants is carried through the air in the spring, the more new cases of coronavirus infection.
Scientists analyzed data on SARS-CoV-2 infectivity, pollen levels and weather conditions obtained at 130 observation points in 31 countries on five continents. They also took into account the population density in each area of interest, as well as the effects of various social exclusion measures.
Airborne pollen, sometimes combined with humidity and temperature, has been found to increase infection rates by 44 percent. In the absence of a lockdown, an increase in pollen concentration per hundred particles per cubic meter increases the incidence rate by four percent. Social exclusion measures halve this figure. In addition, scientists advise people at risk to wear masks against airborne particles.