Consecutive days of high temperatures in Shanghai since the weekend have caused a sudden increase in people seeking emergency treatment for colds.

The heat wave continued in the city on Tuesday, with the high temperature hovering around 36 C after breaking a record in each of the past three days.

Nurses from Shuguang Hospital in Shanghai's Huangpu district said the number of people seeking emergency treatment is noticeably higher and 20 percent more patients required injections or transfusions.

Most of these patients were treated for fever.

Li Jianyun, a white-collar worker, sought treatment during her lunch break from work. She attributed her illness to the huge difference between the indoor and outdoor temperatures.

Few people welcome the sweltering heat, but beverage and ice-cream sellers see it as an opportunity to make a killing.

"Beverages and ice cream sales have tripled in the past few days," said Li Bo, the owner of a grocery store in the Shanghai's bustling Xujiahui shopping area.

Bottled water vending machines are doing brisk business. Almost all the mineral water and other beverages in vending machines in Xujiahui metro station were sold out on Tuesday afternoon.

The heat will stay above 35 C for another week, according to the Shanghai Meteorological Bureau, and the temperature is expected to peak at 38 C on Wednesday and Thursday.

Temperatures also soared on Tuesday in other parts of the country, including Hebei, Jiangxi, Zhejiang and Fujian provinces, according to the National Meteorological Center. The heat is expected to continue for the next three days.