Lower COVID-19 mortality in Italian forested areas suggests immunoprotection by Mediterranean plants14 Aug 2020 00:00
This is a very important work in the discovery of plant derived anti-COVID-19 drugs from Laurus Nobilis, one of the more known mediterranean plants and on the correlationship between COVID-19 severity and forest coverage
Greener zone of south Italy seemed to be less touched by COVID-19 effects and this correlates with factors such as climate, probably mediterranean diet, and, which is suggested in this study, with evergreen forest coverage.
Plant emitted VOCs (volatile organic compounds) inhalated by people living in green mediterranean areas are suggested to bolstering human immune system, whilst mediterranean plants (used in food preparation) contain phytochemicals with potential anti-COVID-19 activity
The COVID-19 pandemic has induced dramatic effects on the population of the industrialized north of Italy, whereas it has not heavily affected inhabitants of the southern regions. This might be explained in part by human exposure to high levels of fine particulate matter (PM) in the air of northern Italy, thus exacerbating the mortality. Since trees mitigate air pollution by intercepting PM onto plant surfaces and bolster the human immune system by emitting bioactive volatile organic compounds (VOCs), we hypothesize a protective role of evergreen forested areas in southern Italy. We compared the mortality rate due to COVID-19, the death number, the positivity rate and the forest coverage per capita in various Italian regions. Hectares of forest per capita and prevalence of deciduous versus evergreen forestal species were also estimated. In silico docking studies of potentially protective compounds found in Laurus nobilis L., a typical Mediterranean plant, were performed to search for potential antivirals. We found that the pandemic's severity was generally lower in southern regions, especially those with more than 0.3 hectares of forest per capita. The lowest mortality rates were found in southern Italy, mainly in regions like Molise (0.007%) and Basilicata (0.005%) where the forest per capita ratio is higher than 0.5 Ha/person. Our findings suggest that evergreen Mediterranean forests and shrubland plants could have protected the southern population by emission of immuno-modulating VOCs and provision of dietary sources of bioactive compounds. Moreover, in silico studies revealed a potential anti-COVID-19 activity in laurusides, which are unexplored glycosides from bay laurel. Overall, our results highlight the importance of nature conservation and applications to the search for natural antivirals.