India's heatwaves worsening, but no one knows how many dying
New Delhi: On a scorching May afternoon last year, a ragpicker in Delhi's Ghazipur area collapsed from heat exhaustion. "The family rushed him to the hospital," says Majida Begum, a sanitation worker who witnessed it. "But he was declared dead on arrival. They had no proof that he died due to heat, so they were not given any compensation." His death was never officially counted, just one of the countless lives lost in India's intensifying heatwaves that go unrecorded and uncompensated.
An investigation reveals that disjointed, outdated reporting systems are obscuring the true toll, weakening both public awareness and policy action. Accurate data on heat-related deaths helps identify who is most at risk. Without it, the government cannot plan effectively, create targeted policies or take timely action to save lives. But behind the missing numbers are real people, many poor and undocumented, whose deaths routinely slip through the cracks of India's incoherent reporting system. Currently, at least three separate datasets attempt to monitor heatstroke or heat-related deaths. The two most-commonly cited in the media are maintained by the National Centre for Disease Control (NCDC) under the health ministry and the National Crime Records Bureau (NCRB) under the home ministry. The India Meteorological Department (IMD) also carries figures on deaths caused by "heatwaves" in its annual reports, drawing data primarily from media coverage.
However, these three sources report widely-varying numbers. For instance, data obtained through an RTI query from the health ministry shows 3,812 heat-related deaths recorded between 2015 and 2022 under the Integrated Disease Surveillance Programme (IDSP), managed by the NCDC. In contrast, NCRB figures, cited in Parliament many times by Union Earth Sciences Minister Jitendra Singh, put the number at 8,171 deaths from "heat/sunstroke" during the same period. Meanwhile, the IMD's annual reports record 3,436 deaths due to "heatwave" between 2015 and 2022. While the NCDC and the IMD have already released the figures for 2023 and 2024, the NCRB is yet to publish the data for these years.
Since 2015, the health ministry has been collecting data on heat illness and deaths from April to July. In 2019, this was extended to March through July, covering 23 states. The NCRB has recorded heatstroke deaths since 1995, listing them as "accidental deaths from forces of nature" since around 2010. Media spoke to government officials and healthcare-policy experts to understand the large discrepancies between these datasets. A senior Delhi Police official explained that the NCRB data largely reflects the number of unattended individuals found dead by police at public spaces, homes and elsewhere. Such bodies are taken to hospitals where doctors conduct autopsies to determine the cause of death. According to the NCRB, 730 people died from "heat/sunstroke" in 2022, 374 in 2021 and 530 in 2020. By contrast, the NCDC data shows just 33 heat-related deaths in 2022, none in 2021 and four in 2020, as many states failed to report their figures. These states included Delhi, Uttar Pradesh, Rajasthan, Punjab, Haryana, Madhya Pradesh, Chhattisgarh, Bihar, Jharkhand, Karnataka, Kerala, Andhra Pradesh, Telangana, West Bengal and Tamil Nadu.
A health ministry official, speaking on the condition of anonymity, said the data from the NCRB and the NCDC are "not directly comparable" because they originate from different sources. "The NCDC reports deaths of patients who come to hospital OPDs or are admitted. But if a person dies and is brought for autopsy, that data goes to the forensic medicine department, which may not always share the information with the NCDC," the official said. He acknowledged the existence of multiple datasets on heat deaths in India and noted that "none of those alone gives the full picture". "While knowing the actual number of heat deaths is important for policy making, confirming such deaths is difficult even with health ministry guidelines," he added. The official said surveillance systems often capture only a fraction of actual cases for other communicable and non-communicable diseases. "We have some numbers, but never the full picture," he said.
One major challenge in data collection is the absence of an electronic record system. "Healthcare facilities still enter data manually. Confirming heat-related deaths is already difficult and manual data entry makes accurate reporting even harder," said another official. Though the Integrated Health Information Platform (IHIP) enables digital submission of surveillance data like that of heat-related deaths, the hospital staff manually enter the information into online forms. There is no automated data transfer from hospital records. Officials also said that while states are mandated to report data, compliance is poor. For example, the hospital staff sometimes omit reporting if temperatures drop due to cloudy weather. A senior doctor from a central government-run hospital in Delhi, speaking anonymously, said most hospitals are understaffed which hampers proper data collection and timely reporting.
The doctor also alleged that authorities may suppress death figures to avoid compensation liabilities. At the India Heat Summit 2025 in May, health ministry Advisor Soumya Swaminathan highlighted the weaknesses in the country's death-reporting systems. "I have been saying this since my time at the Indian Council of Medical Research -- death-reporting systems need strengthening because they provide the best source for the government and policymakers to understand causes of death, which should inform policy," she said. Abhiyant Tiwari, Lead for Climate Resilience and Health at NRDC India, said attributing deaths directly to heat remains a global challenge, not just in India. Tiwari, who has contributed to heat action plans at city and district levels, said the all-cause mortality data is more reliable for assessing vulnerability and setting early-warning thresholds, as it captures the total number of deaths during heat events, not only those officially classified as heatstroke deaths. Many heat-related deaths go unrecorded or are misclassified as heart attacks or other causes. By comparing mortality during heatwaves to normal periods, experts estimate that the excess deaths are likely attributable to extreme heat, he said. He stressed the need to improve the reporting of the all-cause mortality data and suggested appointing a single department responsible for its collection and dissemination. As climate change intensifies heatwaves, Avinash Chanchal, deputy programme director at Greenpeace South Asia, called for urgent reforms in how heat-related deaths are recorded. "Discrepancies between departments and widespread underreporting mean the true toll of extreme heat often remains hidden. The government must understand that hiding or ignoring the true numbers delays the urgent action needed to address heat," he said. Until India fixes its fractured data system, the dead will remain just a number or worse, not counted at all, Chanchal said.
