The world's most polluted mega city- New Delhi- is once again shrouded in a blanket of thick smog. Pollution levels are over 50 times permissible limits. This was after firecrackers were set off to celebrate the Hindu festival of Diwali despite a court ban. Neha Poonia reports on how children are bearing the brunt of this air pollution in India's capital city.

Just like his toy cars, air purifiers and anti-pollution masks are constant companions for 4-year-old Avyan. He suffers from severe wheezing and chest infections - often leading to multiple hospitalizations this time of the year.

ANCHAL GARG KARANTH DELHI RESIDENT "Whenever I put a mask on him for giving him the nebulizer, some part of me cries. One I am pumping him with all those strong medicines, just to manage those symptoms and the other is that his body really needs that to survive in this environment. We want him to have a very nice happy healthy childhood, but it is sad that we are not able to give him that to him, just because we're in the place which has so much pollution."

Avyan knows the smog is to blame but doesn't understand why it must restrict his mobility.

AVYAN KARANTH DELHI RESIDENT "I really get bored at home, there are swings and slides outside, I don't have those at home."

As Delhi gasps for clean air, it's the children that can suffer the most.

NEHA POONIA NEW DELHI "Recent studies have shown that one in every three children in Delhi has impaired lung function according to the Centre of Science and Environment. Doctors also say a newborn baby in Delhi is taking in gulps of polluted air which is same to smoking 25 cigarettes on the first day of its life."

According to the WHO, over 100,000 children below the age of 5 died because of air pollution in India in 2016 - the highest rate in the world. Children are particularly vulnerable to bad air because they breathe more rapidly than adults and absorb twice as many pollutants.

ANUPAMA GUPTA PAEDIATRICIAN "If you are not oxygenating very well. your cognitive function in terms of behavior, intelligence, has a major impact, especially if it happens in the younger years, because that is when the neurological system is really developing. Apart from that, any lung issue could impact the cardio vascular system as well."

Delhi's smog is a toxic mix of vehicular pollution, construction dust and fumes from crops burnt by farmers in neighboring states. This year, the Delhi government banned all construction, digging and excavation work once pollution levels started rising. It's also speaking of taking private cars off of Delhi's roads if pollution levels deteriorate further."

ANUMITA ROY CHOWDHARY ENVIRONMENTALIST "In emergency response you are not solving the problem, but what you are doing is you are stopping from adding more where the situation is already very bad, but the more fundamental solution will come when you are doing a more round-the-year plan and a very stringent implementation of that plan."

The Indian government is currently working on a national clean air plan and has suggested it aims to reduce air pollution by 30% in the next five years. But until there's concrete action on the ground, it's children like Avyan who can't breathe easy. Neha Poonia, CGTN, New Delhi.