Covid can use pollen to transmit faster: Study

CHANDIGARH: Just days after a Lancet study indicated that the Coronavirus is predominantly transmitted through air, a study by a group of Chandigarh-based researchers, has highlighted the possibility that pollen can serve as an effective carrier for the SARS-CoV-2 virus and enhance the viral transmission.

The research has been published in the international journal, Elsevier. In most parts of India, pollen season is currently on and coincides with the start of spring in March and the number of positive Covid-19 cases are seeing an exponential rise.
Another key observation of the study is that patients suffering from allergic rhinitis and asthma were found to have pre-modified immune activation, which could help provide them protection against novel coronavirus. It implied that the immune response generated among people allergic to pollen offers them protection against the SARS-CoV-2 virus.
The research team of Khaiwal Ravindra, Akshi Goyal and Suman Mor from the department of community medicine and School of Public Health, PGIMER-Chandigarh and Panjab University's department of environmental studies did a systematic review of the previous medical literature on MERS (Middle East Respiratory Syndrome), SARS-CoV, and H1N1 viruses, where bioaerosols were a transmission route.
Airborne pollen constitute big fraction of bioaerosols: Study
They explored the effect of pollen on the behaviour of the novel coronavirus to understand whether there were other factors apart from not following the Covid-19 protocols that fueled the latest spike in the cases. “So, we decided to understand environmental linkage which had been observed in the previous SARS CoV viruses. It is necessary to get an idea of the effect of the pollen on those viruses for effective control of such infectious diseases. If we know the pollen size in a week, accordingly it can be used to predict the onset or end of an epidemic," said Dr Suman Mor.
The research team documented that airborne pollen constitute a significant fraction of bioaerosols and serve as carriers for various bacteria and viruses. “They are greatly influenced and triggered by meteorological factors — such as temperature, relative humidity, rainfall, and wind, etc — and jointly can explain the effect on SARS-CoV-2 virus,” said Dr Mor.
The exact pathogenesis of Covid has not been decoded yet, but it is well known that the virus has the ability to spread via dispersal of bioaerosols from an infected person. This study explains that there is a possibility of the pollen-virus complex which may diffuse into the atmosphere and can be transported to long distances from their original site. This could be one of the possible reasons for the rapid spread of this virus.
Based on the existing studies on similar viruses, the review also inferred that there is a correlation between wind speed and crowd and dispersal of pollen in the cities. Therefore, places that are crowded and have high wind speed, will have more dispersal of airborne pollen and thus greater transmission of the virus. “Viruses have the potential to be absorbed on the pollen over the surface and may remain in the atmosphere for hours, days, or weeks. The study provides evidence that Covid transmission is airborne. Lancet’s commentary also supports this argument,” said Dr Mor.