Modelling the links between transport, air quality and COVID-19 spread using naturalistic data from Dhaka, Bangladesh

The aim is to investigate the effects of covid-19 related policy interventions on the transport outcome and correlating these with potential changes in air quality, traffic fatality and spread of the disease.

Transport clearly has a large role in spreading contagious diseases. Standard response to fighting COVID19 in most developed countries has been imposing a lockdown – including on the transport sector – to slow down the spread. Though the Government of Bangladesh also imposed a lockdown quite early, due to economic reasons, it was forced to relax the lockdown.

Decisions from the leaders of the garment sector also led to changes in transport activities and potential step-changes in COVID19 spread. This makes the country, and its capital, Dhaka, a one-of-a-kind ‘living-lab’ to study the interaction between policy decisions, transport impacts, air quality impacts at several discrete steps. The significant policy changes also occurred quiet early on when the infection rate and death rate were still increasing.

Very few (if any) countries in the world – either low income or high income – can offer this unique naturalistic experiment opportunity to study these linkages between external policy or business decision-induced changes in transport activity and COVID19 spread.

Impact

The project is especially useful in understanding the differential impacts of different policy measures on transport, air quality and COVID19 spread, and thus help future evidence-based decision making. This study assesses the interactions between policy interventions, and transport, air quality and COVID-19 impacts in Bangladesh. Using aggregate time-series models relative contribution of different policies on mobility outcome and disease spread are estimated.

It is observed that policy interventions played a significant role in controlling the COVID-19 spread in Bangladesh.  In most cases, the policy interventions had the desired effect on COVID-19 infection as well as changes in people’s mobility patterns, although there were a few which were not as effective. Mobility changes were also highly correlated with COVID-19 spread.

There is a lag of approximately ten days between the introduction of an intervention and changes in mobility and corresponding changes in daily infections. Although the policy interventions resulted in a reduction in accidents and related fatalities, when normalised against reduced mobility, accidents and fatalities increased nationally.

Air quality improved noticeably in areas with large construction and transport activities, however, such improvements were not statistically significant in other areas in Dhaka. The outcomes of the project are especially useful in understanding the differential impacts of different policy measures on transport, air quality and COVID-19 spread, and can help evidence based decision making to combat the next waves of COVID-19 or similar pandemics.

You can read the report Modelling the links between transport, air quality and COVID-19 spread using naturalistic data from Dhaka and Bangladesh: Final Report, on the High Volume Transport (HVT) Applied Research Programme website. The summary report for policymakers, Links between Transport, Air Quality and COVID-19 Spread in Bangladesh Summary of Findings, is also available.

Further reading

A newspaper article on the leading newspaper in Bangladesh (in Bengali).