A&E Admissions Rise In Britain's 30C Heatwave Hospitals have reported a rise in A&E admissions as Britain's 30C heatwave continues. Doctors at North Middlesex University Hospital said they have treated people for severe dehydration, heatstroke and breathing difficulties. In Plymouth, the Derriford Hospital urged people to take extra care after heat-related admissions soared. A Level Three health warning has been put in place by the Met Office in London, the South East, the West Midlands, and the South West due to the unusually high temperatures. Public Health England advised people to stay out of the sun between 11am and 3pm, store medicines in the fridge and keep an eye on elderly neighbours. Crowds of people have headed to the beach in the hot weather The aged, the very young, and those with respiratory and cardiovascular illnesses, are among those most at risk. "The risk of death and risk of illness really concerns us," Professor Virginia Murray, head of extreme events and health protection at Public Health England (PHE), said. Those with pre-existing illnesses are at much greater risk of not being able to cope with heat. It's much harder for them to cope with cooling. She warned that those with breathing difficulties could find themselves struggling to regulate their temperature, while those with heart problems were more likely to suffer a heart attack. As part of the heatwave plan in the South East, high-risk people are being contacted by hospitals. Health experts have estimated that hundreds may have died already as a result of the heatwave. The death toll for the first nine days of the heatwave is between 540 and 760 people in England alone, according to the London School of Hygiene & Tropical Medicine (LSHTM). If the hot weather continues until the end of next week, as many predict, the number could rise substantially. The figures were produced by using temperature data supplied by the Met Office and comparing it with studies conducted on death rates during previous heatwaves in Britain. Ben Armstrong, a professor in epidemiological statistics at LSHTM, said risk increases at temperatures above 26C. "A lot of evidence has been pulled together that the risk in London, for instance, is greatest when it is above 32C in the day and above 18C at night," he said. On Wednesday, temperatures in London reached 32C (89F), the hottest day of the year so far. On Call Clegg the Deputy Prime Minister said that temperatures on London transport were brutally hot, after being told the temperature on a Northern Line tube had hit 35C. He said: "Other countries are used to very hot summers, we are not ready for this. 35 degrees is pretty brutal and you need to be careful, particularly if you're frail. My small kids don't realise when they're overheating. I was padding around in the office wearing no shoes yesterday, and I am relaxed about staff not overheating in my private office - providing they're not engaging in public facing tasks. Extreme heat can lead to heatstroke, in which the body is unable to stay cool - leading to brain damage and death. Temperatures are considered significant if they are high relative to the normal temperature for that area. During the summer of 2003, there were 2,000 excess deaths in Britain.