Scientists are scrambling to find explanations for why the coronavirus outbreak in the Italian north was so much more pervasive and deadly than outbreaks in other parts of Europe, and even other parts of Italy. Some have proposed that Italy's elderly population might have something to do with it - though Japan's demographics are similar, and the outbreak in that country has been far less deadly.
Now, a team of researchers who have been studying air pollution levels in Italy's Bergamo Province have found more evidence that the virus can travel on air pollution particles, the Guardian reports, which might offer some insight into the issue.
Leonardo Setti at the University of Bologna in Italy, who led the work, said it was important to investigate if the virus could be carried more widely by air pollution.
"I am a scientist and I am worried when I don’t know,” he said. “If we know, we can find a solution. But if we don’t know, we can only suffer the consequences."
To be sure, while the scientists found evidence of viral genetic material on air particles, the research offers no insight on whether these particles can actually transmit the virus in a way that would allow it to infect other humans.
Here's more from the Guardian:
The Italian scientists used standard techniques to collect outdoor air pollution samples at one urban and one industrial site in Bergamo province and identified a gene highly specific to Covid-19 in multiple samples. The detection was confirmed by blind testing at an independent laboratory.
The potential role of air pollution particles is linked to the broader question of how the coronavirus is transmitted. Large virus-laden droplets from infected people’s coughs and sneezes fall to the ground within a metre or two. But much smaller droplets, less than 5 microns in diameter, can remain in the air for minutes to hours and travel further.
Experts are not sure whether these tiny airborne droplets can cause coronavirus infections, though they know the 2003 Sars coronavirus was spread in the air and that the new virus can remain viable for hours in tiny droplets.
But researchers say the importance of potential airborne transmission, and the possible boosting role of pollution particles, mean it must not be ruled out without evidence.
Setti isn't the first researcher to find evidence that air pollution particles could enable the virus to travel further by essentially hitching a ride on the particles. According to the Guardian, two other research projects have arrived at similar findings.
A statistical analysis of the data by Setti suggests that higher levels of pollution might explain - or partly explain - the higher rates of infection in Northern Italy, which is more industrious, and struggles with higher levels of air pollution (it's one of the most badly polluted areas in Europe). By contrast, the impoverished Italian south has an economy that's more agrarian in its focus.
None of these studies have been peer reviewed - at least not yet. But a link between air pollution and infection levels is ever definitively proven, at least readers can find solace in the fact that the global economic shutdown has helped reduce air pollution levels around the world - at least for now.