Filenews 9 July 2021
Long-term exposure to high levels of air pollution, especially in microparticles (PM2.5), appears to play a key role in the outcome of patients hospitalized with Covid-19 infection, according to a large multicenter study presented at the annual European Congress of Clinical Microbiology and Infectious Diseases (ECCMID).
In fact, the greater the exposure, the greater the risk: for each minimum increase in long-term exposure to PM2.5, the chances of mechanical ventilation were more than tripled and the chances of hospitalization in an Intensive Care Unit (ICU) were doubled.
Dr. Anita Shallal from Detroit's Henry Ford Hospital and her colleagues studied the relationship between air pollution and the severity of The Covid-19 infection by analysing data on 2,038 adults admitted to four major hospitals between March 12 and April 24, 2020.
Among the elements assessed were the place of residence of the patients and the levels of environmental pollution in the area of residence. Particular emphasis was placed on the relationship between the course of Covid-19 infection and the patient's history of exposure to microparticles (PM2.5), ozone pigments containing lead, vehicle pollutants, hazardous waste and garbage.
It was eventually found that men of African-American descent who were obese or those who had severe chronic underlying health problems were more likely to need mechanical breathing support and admission to ICU. The same was true for those living in areas with high levels of microparticles and lead-containing pigments.
Even when factors that may play a role in the severity of Covid-19 infection, such as age, body mass index and underlying health problems, were taken into account, male sex, obesity and underlying diseases were a predictor of death. Similarly exposure to microparticle pollution was an independent predictor of mechanical ventilation and introduction to the ICU, but did not increase the risk of death.
"Long-term exposure to air pollution may weaken the immune system, resulting in increased vulnerability to viruses and more serious viral infections. Microparticles may also be vehicles for transporting viruses, thus increasing their spread. In any case, the issue needs to be studied in depth in order to take the necessary public health measures in time of pandemic," notes Dr Shallal.
