New Delhi: Air pollution has emerged as India’s most serious public health crisis since the Covid-19 pandemic and will continue to worsen year after year unless urgent, large-scale action is taken, senior doctors have warned. Medical experts say the country is facing a looming tsunami of respiratory and cardiovascular disease driven by prolonged exposure to toxic air, much of which remains undiagnosed and untreated, quietly building pressure on an already stretched healthcare system.

Speaking to PTI, multiple senior doctors practising in the United Kingdom, including Indian-origin specialists with decades of experience, said the impact of air pollution in India is far more severe than official data suggests. They cautioned that what is currently visible in hospitals and clinics represents only a fraction of the true burden of disease, particularly in north India, where air quality frequently slips into the “very poor” or “severe” categories during winter.

Consultant pulmonologist Manish Gautam, based in Liverpool and a former member of India’s Covid-19 Health Advisory Committee, described air pollution as a slow-burning emergency. “Air pollution is arguably the biggest public health crisis India has faced since the pandemic. Unless urgent action is taken, it will continue to worsen every year,” he said. Gautam warned that years of sustained exposure have already caused irreversible damage to the lungs of millions of people.

“What we are managing right now is just the tip of the iceberg,” he said. “A vast, hidden burden of undiagnosed airway disease is building beneath the surface. For millions living in north India, the damage has already been done.”

Doctors say this hidden burden includes asthma, chronic obstructive pulmonary disease (COPD), early lung fibrosis and other airway disorders that often go undetected until they become severe. Many patients, particularly young adults and first-time sufferers, dismiss early symptoms as seasonal illness or minor infections.

The warning comes at a time when hospitals in Delhi and other major cities are reporting a sharp rise in respiratory cases. According to doctors, Delhi hospitals alone saw a 20 to 30 per cent increase in patients with respiratory complaints in December, including a significant number of young adults and people with no prior history of lung disease.

While pollution control measures such as restrictions under the Graded Response Action Plan (GRAP) offer temporary relief, Gautam said they are no longer sufficient on their own. “Prevention is critical, but it is not enough anymore. Years of exposure mean that a lung health emergency is already unfolding,” he said, calling for early detection programmes and the creation of a rapid “lung health task group” to identify and treat airway disease at scale.

The doctors also challenged the idea that rising cardiovascular disease rates are driven primarily by obesity and lifestyle factors alone. Rajay Narain, honorary cardiologist at St George’s University Hospital in London, said there is overwhelming scientific evidence linking air pollution to a wide range of diseases, including heart disease, stroke, respiratory illness, neurological disorders and systemic inflammation.

“Any delay in addressing air pollution will only add to the health and economic burden,” Narain said. He stressed that while short-term measures may reduce immediate exposure, the real solution lies in sustained, science-driven policies that prioritise clean air, protect vulnerable populations and hold polluters accountable.

Narain warned that early warning signs of pollution-related illness are often ignored. Symptoms such as headaches, fatigue, mild cough, throat irritation, digestive discomfort, eye dryness, skin rashes and recurrent infections are frequently dismissed as minor problems, he said, but may indicate the early stages of serious chronic disease.

Another senior cardiologist, Professor Derek Connolly of Midland Metropolitan University Hospital in Birmingham, said the cardiovascular risks of air pollution are largely invisible to the public. “Cardiovascular disease is an extremely slow process, with episodes of rapid deterioration. This is a silent killer,” he said.

Connolly explained that unlike blood pressure or cholesterol, particulate matter cannot be easily sensed or measured by individuals. “People are unaware of their exposure because particulate matter is invisible. We are all exposed to it, even on days when pollution does not seem too bad,” he said.

He added that while the rise in cardiovascular disease over the past decade has often been attributed to obesity, a significant portion of it may be linked to the rapid increase in automobiles and air travel, which release toxic substances into the atmosphere. “Urban transport emissions, including from cars and aircraft, are playing a much larger role than we acknowledge,” Connolly said.

Data from India itself supports these concerns. During the winter session of Parliament, the health ministry stated that more than two lakh cases of acute respiratory illness were recorded in Delhi over the past three years, with around 30,000 patients requiring hospitalisation. Despite this, the government reiterated that there is no conclusive data establishing a direct causal link between higher Air Quality Index (AQI) levels and lung disease or mortality, although it acknowledged air pollution as a triggering factor for respiratory ailments.

This position has drawn criticism from health experts, who argue that waiting for “conclusive” proof risks delaying life-saving action. “The science linking air pollution to disease is already robust,” Narain said. “What we need now is policy courage.”

Union transport minister Nitin Gadkari recently acknowledged that nearly 40 per cent of Delhi’s pollution is caused by the transport sector due to dependence on fossil fuels. He emphasised the urgent need for cleaner alternatives, including biofuels, electric mobility and sustainable transport systems. Doctors say such admissions must translate into rapid and measurable policy changes.

The scale of the problem is underscored by global research. According to the 2025 Report of The Lancet Countdown on Health and Climate Change, PM2.5 pollution led to more than 17 lakh deaths in India in 2022 alone. Of these, petrol use in road transport contributed to approximately 2.69 lakh deaths.

A separate global study by the International Council on Clean Transportation, published in May, found that policies targeting road transport emissions could save 1.9 million lives worldwide and prevent 1.4 million new cases of childhood asthma by 2040.

Doctors say India has demonstrated before that large-scale public health interventions are possible. Gautam pointed to the country’s fight against tuberculosis, where early diagnosis, structured treatment programmes and sustained investment have significantly reduced disease impact. “A similar level of urgency and investment is now required for airway diseases,” he said.

Healthcare professionals have repeatedly warned that air pollution is no longer an environmental issue alone but a full-blown health emergency. Without aggressive action on emissions, early screening and long-term healthcare planning, they say India risks facing a prolonged crisis that could rival — or exceed — the health toll of Covid-19.

“The cost of inaction will be paid not just in hospital beds and healthcare spending,” Narain said, “but in lost years of healthy life for millions of Indians.”