Covid-19 risk greater in urban centres affected by air pollution


People living in polluted cities are more at risk from Covid-19, according to health experts cited in a 16 March report from the European Public Health Alliance (EPHA), an advocacy group.

Mortality rates for Covid-19 have been linked to the presence of pre-existing conditions such as diabetes, heart disease, and respiratory conditions – all factors with a demonstrable link to air pollution. A 2003 study on victims of the coronavirus SARS found that patients in regions with moderate air pollution levels were 84% more likely to die than those in regions with low air pollution.

The European Respiratory Society (ERS) is an EPHA member. Dr Sara De Matteis, Associate Professor in Occupational and Environmental Medicine at Cagliari University, Italy, and member of the ERS Environmental Health Committee said: “Urban air quality has improved in the last half century, but petrol and especially diesel vehicle fumes remain a serious problem. Even the latest diesel engines emit dangerous levels of pollution. Patients with chronic lung and heart conditions caused or worsened by long-term exposure to air pollution are less able to fight off lung infections and more likely to die. This is likely also the case for Covid-19. By lowering air pollution levels we can help the most vulnerable in their fight against this and any possible future pandemics.’’

Air pollution is the biggest environmental health risk in Europe, with the problem greatest in cities, according to the EEA. Particulate matter (PM), nitrogen dioxide (NO₂) and ground-level ozone (O₃) cause the most harm and lead to about 400,000 early deaths annually. One hotspot is Northern Italy, centre of Europe’s Coronavirus outbreak. Urban NO₂ pollution comes mainly from traffic, especially diesel vehicles, which are also a major source of PM. There has been a sharp rise in the proportion of diesel vehicles across Europe since the turn of the millennium, many of which have failed to comply with European air pollution standards. There have been 71 infringement procedures underway against EU countries for failing on air quality.

Satellite imagery from the European Space Agency (ESA) has revealed a remarkable drop in NO2 pollution around major urban centres that have been a centre of the outbreak, including in China and Northern Italy. And official monitoring stations in Milan reveal a similar effect.

EPHA Acting Secretary General Sascha Marschang said: “The air may be clearing in Italy, but the damage has already been done to human health and people’s ability to fight off infection. Governments should have tackled chronic air pollution long ago, but have prioritised the economy over health by going soft on the auto industry. Once this crisis is over, policymakers should speed up measures to get dirty vehicles off our roads. Science tells us that epidemics like Covid-19 will occur with increasing frequency. So cleaning up the streets is a basic investment for a healthier future.”

Data from the European Space Agency (ESA) reveals a significant clearing of NO2 levels in Chinese cities, which the group estimated as equating to a roughly 40% drop.

In early March, ESA also said PM2.5 levels over China in February were 20-30% down on the average February levels expected at this time of year (drawing on data from 2017-2019). Speaking to Climate Change News, Kristin Aunan, a senior researcher at at the Center for International Climate Research in Oslo (Cicero), said that – were PM2.5 to remain at this reduced level for an entire year – the annual number of premature deaths that could be avoided could be 54,000 to 109,000.

In China the pandemic has caused a sharp fall in activities that produce these pollutants, including a 36% drop in the use of coal in the country’s largest coal-fired power plant, a resource on which the country still depends for most of its energy production. Falls in industrial activity, and things like oil and steel production, have also been significant, in addition to a 70% drop in domestic flights.