Air pollution is a severe environmental and health problem.
According to WHO, India is the home to the most polluted cities in the world.
Both short term and long term exposure to particulate matter may increase the risk of chronic respiratory diseases such as asthma, bronchitis, COPD, lung cancer, and pneumonia.
And breathing in poisonous polluted air may affect the cardiovascular system and other organs as well.
COVID-19 is a current pandemic outbreak caused by a coronavirus, called SARS-CoV-2, first reported by WHO in December 2019 following a group of viral pneumonia cases in Wuhan, China.
The most common symptoms are fever, dry cough, and fatigue. The severe COVID-19 infection may cause shortness of breath, loss of appetite, confusion, pain in the chest, and even death.
Presently, scientists around the world are working to develop vaccines and treatment modalities for COVID-19. 
India faces a severe air pollution crisis and our cities dominate the top 10 and top 50 most polluted cities in the world.
As COVID-19 is mainly a disease of the respiratory system, it is essential to know that if the exposure to air pollutants can increase the susceptibility, and the vulnerability of the COVID-19 patients. This article analyzes the possible correlation between COVID-19 and air pollution.
Table of Contents
- How does air pollution impact COVID-19?
- 1. Air pollutants may spread the coronavirus infection
- 2. Air pollution may weaken the immune system and increase the risk, the severity of COVID infection
- 3. Air pollution and COVID-19 may increase the risk of developing co-morbidities
- 4. Air pollution may increase the risk of dying from coronavirus
- 5. Impending winter and indoor pollution may aggravate the COVID-19 burden
How does air pollution impact COVID-19?
It should be kept in mind that it would need more time and research to fully understand this relationship and the current article is based on research available right now. We will keep the article updated with latest developments going forward.
The main route of viral transmission is believed to be through human respiratory droplets and direct contact.
However, a preliminary study suggests that SARS-CoV-2 virus may be dispersed more widely on air pollution particulate matters, PM2.5 and PM10.
These particles may provide a more particulate surface for the virus to stick, act as a vehicle of viral transmission, enhance the persistence of the virus in the atmosphere and increase the chance of people from getting sick from COVID-19.
Some researchers suggest that the virus may survive longer when attached to the particulate matter and remain suspended in the air.
More studies are required to make a correlation between the presence of a virus on particulate matter and progression of COVID-19.
2. Air pollution may weaken the immune system and increase the risk, the severity of COVID infection
According to the European Public Health Alliance, air pollution may compromise cellular composition, damage the airways epithelial barriers, and weaken the body’s immune response to pathogens.
The individuals with compromised immune response are at a higher risk of COVID infection as they have weak immunity to fight off viral load in the body.
Also, air pollutants may exert excess pressure on the patient’s respiratory system to fight the viral infection and exacerbate asthma, COPD and other pulmonary diseases.
Another hypothesis is that air pollutants may increase the expression of ACE2 receptors found in the nose, throat and lungs.
Coronavirus latches on the ACE2 receptors and enters the cells. The increased expression of ACE2 receptors may increase a load of coronavirus in a person and impair the immune defence of the host.
3. Air pollution and COVID-19 may increase the risk of developing co-morbidities
The long term exposure to the particulate matter released due to air pollution causes severe inflammation and oxidative stress.
It may damage the inner lining of the arteries, speeding up the calcification of arteries leading to clogged arteries and exacerbate a wide range of cardiovascular illnesses.
COVID-19 also may cause similar damage to the blood vessels due to disproportionate immune system reactions and results in the formation of blood clots.
Therefore, if both air pollution and COVID-19 come together, they may cause an additive adverse effect on heart and blood vessels.
If having underlying heart disease, diabetes, obesity, then COVID-19 and air pollution together may increase the risk of developing a heart attack, stroke and multiorgan failure.
Some scientists have suggested that air pollution may have worsened the outbreak and increased the deaths due to COVID-19.
A study by Harvard school of public health reported that an individual who lives exposed to high levels of fine particulate matter long term is 8% more likely to die from COVID-19 compared to someone who is exposed to one unit less of such pollution.
Another study suggested that a high level of pollution in Northern Italy may act as a cofactor for the high levels of mortality due to SARS-CoV-2.
A 2003 study reported that each ten microgram elevation in the particulate matter 10 increased the risk of cardiopulmonary mortality by 6% due to SARS, a virus closely related to COVID-19.
According to the European Protection Agency, a decrease in one microgram of particulate matter per cubic meter of air may reduce the number of new COVID cases by 2% and deaths due to COVID by 3 to 5%.
5. Impending winter and indoor pollution may aggravate the COVID-19 burden
Pollution levels increase every autumn and winter due to agricultural waste burning, industry emissions, vehicle fumes and brick kilns.
As a result, there is more concentration of particles in the air that stays for a longer duration of time.
Also, women in rural areas are more susceptible to household air pollution due to exposure to biomass like fuelwood or animal dung.
The experts warn that bad air during winter, and household air pollution may worsen the spread and severity of coronavirus, leading to complications like pneumonia due to compromised lungs.
Preliminary studies have identified the possible connection between air pollution and COVID-related mortalities.
However, more research studies are required to understand what fraction of the burden of COVID-19 could be attributable to ambient air pollution.
The existing studies suggest the importance of enforcing air pollution regulations to minimize the effects of coronavirus and protect human health during and after the COVID-19 crisis.