Perjantai 24.4.2020 klo 16:48 - Mikko Nikinmaa
The incidence of coronavirus infections has been lowest in islands or island-like areas (e.g. Australia, New Zealand, South Korea, Taiwan, Finland, Iceland, Alaska). Generally, they are sparsely populated and not important for through-traffic. However, both Taiwan and South Korea have high population densities. The low number of coronavirus infections in South Korea has usually been explained with early onset of restrictions and early start of intensive testing. That interpretation is not entirely convincing, since early onset intensive testing has also been done in places with high counts of coronavirus infections. Further, significant differences in coronavirus-induced mortalities occur between areas with high numbers of coronavirus infections.
Two articles published in the Science of the Total Environment have now, in my opinion, completely clarified both these outstanding issues. Both the incidence of infections and the lethality of infections is increased by air pollution. Especially nitrogen dioxide but probably also ozone and particulate matter increase both the incidence of coronavirus infections and the mortality caused by them (Zhu et al. Science of the Total Environment 727 (2020) 138704; Ogen Science of the Total Environment 726 (2020) 138605). In every sparsely populated place also the nitrogen dioxide level is low, but it is quite low also in Taiwan and South Korea, since the pollution does not stagnate in the area. In contrast, the polluted air remains in Lombardia and Madrid area, where coronavirus cases and mortalities abound. Also, Paris, London and New York area likely have high nitrogen dioxide level – and all have high number of coronavirus mortalities. In contrast, at least partially the low coronavirus mortality in Germany associates with relatively low nitrogen dioxide levels even in the densely populated areas.
Thus, air pollution, to a large extent because of car traffic, has significant connections with coronavirus infections. They are symptoms of the same problem, our overuse of the planet. Population bomb, talked much of in 1960-1970’s, increases the likelihood of future pandemics. An Indian author pointed out that because of the decreasing space for wild animals, their interactions with man may cause the birth of next pandemic in India ( S. Minhas, Could India be the origin of next COVID-19 like epidemic?, Science of the Total Environment (2020), https://doi.org/10.1016/j.scitotenv.2020.138918)