Summary

South Asia is at the epicenter of the global air pollution problems and still evolving in COVID-19 cases and fatalities. There is growing evidence of increased rates of COVID-19 in areas with high levels of air pollution. Air pollution is found to cause cellular damage and inflammation throughout the body and has been linked to higher rates of diseases, including cancer, heart disease, stroke, diabetes, asthma, and other comorbidities. All these conditions also potentially increase the risk of death in COVID-19 patients. The causal link between the exposure to air pollution and COVID-19 is still under investigation around the world, underpinned by rigorous scientific research and peer-review processes. However, in terms of the approach after a careful review of the literature, the instrumental variable (IV) approach is a prospective candidate to establish causality in a reduced-form analysis to overcome endogeneity and measurement errors of air pollution level. An analysis, therefore, using sufficiently anonymized individual and household level information on COVID-19, household air pollution, and other individual and household socioeconomic endowments in the same primary sampling unit (PSU) of the individual and household survey would be necessary to establish the causality. The PSU data are usually available from demographic health surveys (DHS) with randomly displaced location information to maintain anonymity. Also, for the instrument of the exposure to ambient air pollution, the use of thermal inversions is suggested conditional on weather-related variables—for example, temperature, precipitation, wind velocity and direction, and humidity.