Potential Changes in Air Pollution Associated with Challenges over South Asia during COVID-19: A Brief Review

The severe acute respiratory syndrome (SARS-CoV-2), also referred to as COVID-19 originated in the Wuhan city of Hubei Province of China in late December 2019 and spread to more than 200 countries, including many in Southeast Asia. This review has established a close relationship between the spread of coronavirus and air pollution and suggests that the prevailing environmental factors played a role in the spread of infection in the region. The rate of coronavirus transmission significantly declined as effective strategies and measures such as lockdowns, quarantine curfews, and country-wide lockdowns were adopted, eventually resulting in a dramatic improvement in air quality in different South Asian countries. The imposition of the lockdown improved air quality, contributing to lower incidences of COVID-19 infection and fatality rates across the region. Studies conducted by various scientists indicated a significant reduction in the level of air pollutants, especially the particulate matter (PM₁₀, PM_2.5) CO, SO₂, and NO₂ due to stringent restrictions on movement, shutting down of most industries, and halting of commercial and construction activities. However, ozone levels did not show any significant decrease. The results provided by the various agencies clearly suggest that the respiratory spread of infections is directly proportional to the air-quality parameters, and steps taken to decrease the particulate matter and other pollutants can help in containing the infection. The studies can help understand the epidemiology of the disease and thus serve as a useful tool for governments to manage the spread of respiratory infections and help mitigate air pollution and disease spread by adopting staggered lockdowns.