Across India, extreme temperatures are being felt most in the country's teeming megacities, where experts say that heat is fast becoming a public health crisis. Ajay Shukla, the director of New Dehli's Ram Manohar Lohia hospital, explains "we have set up the first of its kind heat stroke management unit", adding that "the mortality rate is very high" in a city where temperatures have this week hit the high forties Celsius. IMAGES AND SOUNDBITES