BENGALURU: As temperatures continue to rise across Karnataka, despite temporary relief from sudden rain in some parts, doctors report an increase in heat-related illnesses, with symptoms ranging from dehydration and dizziness to confusion and seizures.
While severe heat stroke cases remain limited, health experts warn that the risks are growing, especially for vulnerable groups such as children, the elderly, pregnant women and outdoor workers.
Heat-related illness often begins with symptoms such as headaches, fatigue, muscle cramps, irritability and dizziness, but can quickly escalate into heat stroke if left untreated. Heat stroke is a medical emergency that occurs when the body’s core temperature exceeds 40 degrees Celsius and loses its ability to cool itself. Normally, sweating helps regulate body temperature. But under extreme heat and severe dehydration, that cooling mechanism can fail.
“Heat stroke is not just dehydration. Once body temperature crosses 40°C, it can affect the brain, trigger seizures, confusion and even coma if treatment is delayed,” said Dr BK Madhusudhan, a neurologist.
Once the body overheats, doctors say the brain is often the first organ to be affected, leading to disorientation, delirium, seizures and loss of consciousness. Other organs, including the heart and kidneys, can also come under stress.
In many parts of the state, hospitals are already seeing patients with early warning signs such as dehydration, severe headaches, giddiness, vomiting and weakness. “There is a rise in dehydration, headaches, fatigue and heat exhaustion, all early warning signs of heat-related illness,” said Dr Ashwin Kulkarni, consultant, palliative care, at a private hospital.
Doctors say children are particularly vulnerable because they lose fluids quickly and often do not realise when they are dehydrated. “Before heat stroke happens, many children first show dehydration through body ache, headaches and fatigue. Regular hydration is the first line of prevention,” said Dr Anil Kumar Pura Lingegowda, HOD, paediatric surgery, of a private hospital.
Parents are advised to restrain children from playing outdoors during peak heat hours and ensure they consume water, buttermilk, tender coconut water and fruit juice regularly.
The elderly and pregnant women are also at higher risk, as they tend to lose water faster and may have lower heat tolerance.
FOOD AND WATER-BORNE INFECTIONS
Apart from dehydration and heat stroke, doctors are also warning of a rise in food- and water-borne infections during extreme heat, as food spoils faster and unsafe hydration practices increase the risk of gastroenteritis. Across hospitals and public health circles, the message remains consistent: prevention is critical.
Outdoor workers at high risk
For outdoor workers, however, avoiding peak heat is often not an option. The Karnataka government has issued advisories recommending access to cool drinking water, shaded rest areas and rescheduling heavy work to cooler parts of the day, while its proposed 2026 Heatwave Resilience Framework identifies construction workers, street vendors, agricultural labourers and the elderly as priority groups, said Apekshita Varshney, founder, HeatWatch.
But she cautioned that advisories alone are not enough. “Advisories only work when there is an employer to enforce them,” she said, pointing out that informal workers often remain outside the protection net. She said a study of waste workers in Bengaluru showed that many spent 6-7 hours outdoors during peak heat without access to shade, mandatory rest breaks or health coverage when they fell ill.
She added that one of the biggest gaps in Karnataka’s heatwave response is the absence of binding protection for informal workers. “All measures are advisory. Waste pickers, gig delivery workers and domestic workers are structurally excluded from every protection on paper,” she said.
She also highlighted the lack of transparency in heat-related illness data. While cases are collected through the Integrated Health Information Platform (IHIP), the data is not publicly accessible or broken down by occupation, making it difficult to assess the impact on outdoor workers. “There is no systematic tracking of occupational heat illness, which means deaths and hospitalisations among informal workers often go unrecorded,” she said.
Varshney called for heat stress to be legally recognised as an occupational health hazard under labour frameworks, with guaranteed access to water, shade and rest for all workers, regardless of employment type.