You are here: Home » Current Affairs » Coronavirus » News
Business Standard

US study links pollution to higher Covid-19 mortality, Indian experts defer

A new analysis of more than 3,000 counties in the US suggests that people with long-term exposure to PM 2.5 may be more likely to die from Covid-19

Topics
air pollution | Coronavirus

Press Trust of India  |  New Delhi/Boston 

New Delhi: A metro train runs on a track amid hazy weather conditions, in New Delhi, Sunday, Nov. 1, 2020. (PTI Photo/Manvender Vashist)
New Delhi: A metro train runs on a track amid hazy weather conditions, in New Delhi, Sunday, Nov. 1, 2020. (PTI Photo/Manvender Vashist)

A new analysis of more than 3,000 counties in the US suggests that people with long-term exposure to PM 2.5 may be more likely to die from COVID-19, leading to increased concern about the trajectory of the disease and its fatality rate in parts of north India battling alarmingly high levels of

Though worried as cases in the Indian capital and its suburbs spike, pulmonologists here said a causal link between fine particle pollutants (PM2.5) and COVID-19 mortality has not yet been established.

The US study, published in the journal Science Advances on Thursday, assessed the impact of long-term exposure to on COVID-19 death rates in 3,089 counties in the US.

The researchers, includingXiao Wu from Harvard University, found that chronic exposure to PM2.5 pollutants -- tiny particles in the air that are two-and-a-half microns or less in width -- is linked to greater county-level COVID-19 mortality rates.

Dispelling some of the panic, experts here said the biological reasons for high rates of COVID-19 infection and deaths in places with high PM2.5 levels are yet to be understood.

"It is not proven currently that PM2.5 levels directly increase chances of infection or death," Piyush Goel, a pulmonologist from Gurgaon's Columbia Asia Hospital told PTI.

Goel explained that PM2.5 particulate matter consists of water vapour, dust particles, and pollutants, which may attach the COVID-19 virus and facilitate its airborne transmission.

"But this is only a school of thought and not confirmed," he cautioned.

"There have been no studies published in India right now which proves this scenario, but this is possible," he added.

According to the pulmonologist, the health of patients who maintained "somewhat stable" chronic lung conditions can become unstable due to the changing season and rising pollution levels.

"And if these patients get lung infection, it will be a more serious complication. The criticality will be high," Goel said.

He said exposure to high levels of pollution can lead to chronic lung disease and also hamper lung development in infants and toddlers.

"There are several studies backed by the World Health Organization which show that this may impact brain development also, and it could lead to lung cancer as well," Goel said.

"From children to full-grown adults, affects everyone in India, but how COVID-19 impacts people exposed to these conditions individually is too soon to tell," he added.

Delhi's air quality index (AQI) was 397 at 10 am on Thursday, when italso saw 6,715 reported COVID-19 cases, taking the infection tally to over 4.16 lakh.

The 24-hour average AQI in the national capital was 450, categorised as "severe" -- the highest since November 15 last year when it was 458 -- raising concerns on how this may impact the COVID-19 caseload.

The National Centre for Disease Control (NCDC) had warned last week that Delhi may report nearly 15,000 COVID-19 cases daily in winter because of the prevalence of respiratory illnesses during this season that worsen the symptoms of the disease.

Commenting on the association between air pollution exposure and death from COVID-19, Anurag Agrawal, director of New Delhi's CSIR-Institute of Genomics & Integrative Biology (IGIB), said both factors can affect the functioning of the lungs and heart, and lead to death.

"But whether the health risk from these is additive or greater remains to be seen," the IGIB pulmonologist told PTI.

The Harvard researchers noted that chronic exposure to PM 2.5 might cause overproduction of ACE-2 receptor proteins in the lungs, which the novel uses to enter host cells.

They believe prolonged exposure to air pollution might also impair people's immune system, compromising their abilities to fight off the novel infection.

"Chronic exposure to PM2.5 causes alveolar ACE-2 receptor overexpression and impairs host defences. This could cause a more severe form of COVID-19 in ACE-2-depleted lungs, increasing the likelihood of poor outcomes, including death," the Harvard scientists wrote in the study.

But they acknowledged that this is only a hypotheisis.

Citing the limitations of their study, the researchers said they were unable to account for individual-level risk factors such as age, race, and smoking status as such data was unavailable.

"This approach leaves us unable to make conclusions regarding individual-level associations," the scientists said

The Harvard scientists believe further research on how pollution and other factors may exacerbate COVID-19 symptoms and increase mortality risk is essential to guide policies and behaviour related to the pandemic.

Agrawal added that pollution levels must be controlled even without considering its association with COVID-19.

"Irrespective of the mathematics, we must strive to bring air pollution down to improve health," he said. PTI VIS SAR


about the trajectory of the disease in India, particularly in parts of the north battling alarmingly high levels of air pollution.

where air pollution is reaching

However, pulmonologists in India, where air pollution is reaching say , however, Indian pulmonologists say a direct connection cannot be made unless the causation for this relationship is established.

(Only the headline and picture of this report may have been reworked by the Business Standard staff; the rest of the content is auto-generated from a syndicated feed.)

Dear Reader,


Business Standard has always strived hard to provide up-to-date information and commentary on developments that are of interest to you and have wider political and economic implications for the country and the world. Your encouragement and constant feedback on how to improve our offering have only made our resolve and commitment to these ideals stronger. Even during these difficult times arising out of Covid-19, we continue to remain committed to keeping you informed and updated with credible news, authoritative views and incisive commentary on topical issues of relevance.
We, however, have a request.

As we battle the economic impact of the pandemic, we need your support even more, so that we can continue to offer you more quality content. Our subscription model has seen an encouraging response from many of you, who have subscribed to our online content. More subscription to our online content can only help us achieve the goals of offering you even better and more relevant content. We believe in free, fair and credible journalism. Your support through more subscriptions can help us practise the journalism to which we are committed.

Support quality journalism and subscribe to Business Standard.

Digital Editor

First Published: Fri, November 06 2020. 18:39 IST
RECOMMENDED FOR YOU