According to Minhang District Center Hospital, two out of the eight patients who suffered serious heat stroke since July 26 have died, despite a series of emergency treatment measures. Treatments include both physical and drug-induced methods of reducing body temperature, correcting dehydration and prevention of multiple organ failure.

"Most of these patients are aged 50 or above and face a higher risk of heat-related medical problems," said Deng Xingqi, a doctor from the Minhang District Center Hospital.

Deng said that among the eight patients, only one became sick outdoors, while the rest suffered heat stroke indoors.

Songjiang District Center Hospital says it has received five serious heat stroke cases, three of them with patients aged over 60. A 70-year-old patient used an electric fan to cool himself down but fainted at home when the outside temperature reached 40 C.

Many older patients have suffered from cardiovascular and cerebrovascular disease for years. The high summer temperatures and high humidity have increased health risks, the doctor said.

In addition to Shanghai, some neighboring provinces have also reported a number of heat-related fatalities. At least seven fatal cases caused by heat stroke were reported in Jiangsu province. And Zhejiang province has reported at least eight deaths from heat stroke, most of them people who spent a long time in the sun.

Doctors advise that those who faint due to heat should be quickly removed to a cool place with plenty of air, and measures should be taken to lower their body temperature, such as pouring cold water on the body or wiping the body with a wet towel. Meanwhile, it's important to give patients lots of water to replace lost fluids, and if possible, salt to replace salts lost through sweating. Rehydration powders mixed with water can be useful for this purpose.

On Wednesday, Shanghai saw the 25th straight day of temperatures above 35 C in July, with its maximum temperature reaching 39.8 C.

The city's meteorological department said the mercury is likely to stay around 39 C in the coming days despite thunderstorms in some parts of the city.

wanghongyi@chinadaily.com.cn