NEW DELHI - As Delhi's air quality starts to deteriorate in what has become an annual occurrence in the run-up to winter, concerns are growing over how the coming pollution could potentially complicate the Covid-19 situation.
India's capital has been among the cities in the country worst affected by the coronavirus pandemic, with more than 300,000 people infected and a death toll of 5,653. On Wednesday (Oct 7), the city recorded 2,726 fresh cases as it battled a second wave.
Health experts fear air pollution could increase the risk for patients who have ailments like chronic bronchitis and other respiratory diseases.
"We might see a spike. Right now the trend is slightly going down but we don't know how air pollution will contribute to an increase," said Dr Chandrakant Lahariya, an expert on public health, policies and strategies, adding that air pollution exacerbates the condition of people who have respiratory or pulmonary disease.
He warned: "There are studies in which air pollution is linked to increased mortality but such evidence is limited."
Studies have also pointed to increased Covid-19 infection rates in areas that suffer from high pollution.
A study by the Harvard T.H. Chan School of Public Health in the US in May found that someone who lived in an area of high-particulate pollution for decades was 8 per cent more likely to die from Covid than someone in a place with less pollution.
A study by environmental scientists at Denmark's Aarhus University and health researchers at Italy's University of Siena found that the mortality rate from Covid-19 came up to 12 per cent in the northern part of Italy, while it was around 4.5 per cent in the rest of the country. The researchers concluded that there was a probable correlation between pollution and mortality.
Delhi could hit 15,000 new coronavirus cases per day because of respiratory problems related to winter and festive gatherings as the festive season kicks off this month, a report by the National Centre for Disease Control has warned.
During the winter months, cold air traps pollutants in the atmosphere, and it is also the time when farmers burn the stubble in their fields to prepare them for the next set of crops.
All this adds to existing pollution from vehicles, construction activity, burning of waste and use of unclean fuels.
A report by the US' Health Effects Institute said around 1.2 million people died in India in 2017 because of air pollution.
According to weather forecasters, pollution levels have already started climbing and will get worse from the middle of October.
Air quality had improved following a stringent lockdown, now eased, that shut down economic activity, and Delhi's air quality turned "poor" this week for the first time since June.
According to Safar (System of Air Quality and Weather Forecasting And Research) under the Ministry of Earth Science, air quality is set to deteriorate further over the next three days as winds will push pollutants into the capital city, where conditions are right for them to accumulate.
Delhi Chief Minister Arvind Kejriwal on Monday announced a campaign against pollution, with plans to control dust by filling up potholes and closely monitoring construction sites, among other measures.
"Polluted air can be life-threatening in view of the Covid-19 pandemic," said Mr Kejriwal, while announcing the measures. "Both affect the lungs."
Environmentalists say the problem with solutions, as in previous years, has been with implementation.
"Delhi has done some things successfully like shutting down (polluting) power plants. But there are still gaps in sectors like waste burning. Our infrastructure for waste management is weak," said Ms Anumita Roychowdhury, executive director of the Centre for Science and Environment. Waste burning is illegal but still happens.
"The time has come to ensure a system audit to see whether you have been able to roll solutions out on the scale needed across all sectors. It's an enforcement challenge."