People who live in areas with poor air quality such as busy roads and factory farms are more likely to become infected with coronavirus and their symptoms are often more severe, leading to more hospitalisations and deaths, according to new Dutch research.

The results, the researchers say highlight the the importance of having cleaner air in the Netherlands, and offer insights for dealing with future pandemics.

The study, carried out by public health institute RIVM, Utrecht and Wageningen universities and regional health boards, shows air pollution does not play a direct role in the process of spreading coronavirus.

But it does confirm other research that air pollution makes respiratory diseases worse.

The researchers looked at the first year of the epidemic, before people had been vaccinated, and found people who live in areas with relatively poorer air quality were more likely to become infected, end up in hospital or die.

Air quality can vary due to high volumes of traffic, industry and intensive livestock farming, the researchers said. In terms of coronavirus, “livestock showed the most detrimental health effect.”

“In the period to 1 February 2021, around 22,500 people died from COVID-19”, the report says. “In the regions where the air quality was worse than the Dutch average, a total of 400 to 800 deaths could have been prevented if the air had been as clean as average. The cleaner the air, the greater the preventive effect.”

Cleaner air would also have prevented 1,100 hospitalisations, the researchers said.

“The outcomes of this study stress the importance of improving air quality in Europe,” the report concluded. “Moving toward the WHO air quality guidelines would improve health generally and reduce the impact of severe acute respiratory infections.”