Study Finds Link Between PM2.5 Levels and COVID-19 Incidence and Mortality Rates

New Delhi: A recent study has highlighted a potential link between environmental factors, particularly fine particulate matter (PM2.5), and the high incidence and mortality rates of COVID-19. Researchers from Taiwan's National Yang Ming Chiao Tung University have proposed that PM2.5 may influence the transmission and severity of the SARS-CoV-2 virus.

PM2.5, known for its harmful effects on respiratory health, has been suggested in earlier studies to act as an environmental carrier that facilitates the transmission of SARS-CoV-2. The new research, published in the Journal of Hazardous Materials, provides experimental evidence supporting this theory.

The study used mice to explore the impact of PM2.5 on SARS-CoV-2 infection. It revealed that PM2.5 exposure increased the protein abundance of ACE2, the receptor through which SARS-CoV-2 enters human cells. The researchers found that instillation of PM2.5 not only upregulated ACE2 expression but also exacerbated SARS-CoV-2 pseudovirus infection in both in vitro and in vivo models.

“Our findings provide the first direct evidence that PM2.5 exposure increases ACE2 expression and worsens SARS-CoV-2 infection. PM2.5 dysregulated the renin-angiotensin system (RAS), increased ACE and ACE2 protein levels in mouse lungs, and raised the severity of infection,” the researchers told IANS.

In parallel, a study conducted by the Barcelona Institute for Global Health (ISGlobal) and published in Environmental Health Perspectives examined the link between air pollution and long COVID symptoms, such as fatigue, breathlessness, and cognitive difficulties. The researchers concluded that while air pollution itself is not a direct cause of long COVID, it can increase the severity of the initial infection, which raises the risk of developing persistent symptoms.

The findings underscore the broader health risks posed by air pollution, emphasizing its role in both acute and long-term COVID-19 outcomes. By increasing the severity of the initial infection, exposure to PM2.5 and PM10 may indirectly heighten the likelihood of long COVID, the ISGlobal team noted.

These studies add to the growing body of evidence on the harmful impacts of air pollution, particularly during the ongoing COVID-19 pandemic.