GUANGZHOU - South China's Guangdong province reported 1,431 new dengue cases on Sunday, bringing the total number up to 21,527, said local health authorities on Monday.

The number was rising quickly, with more than 1,000 new cases found each day last week. One new fatality case was reported by the provincial health and family planning commission on Sunday, bringing the death toll in the province to six.

The latest case was found in the Liwan district in western Guangzhou, Guangdong's capital, which has seen five deaths of dengue so far this year. With 18,192 cases confirmed, Guangzhou is the worst-hit city in the province.

One fatality was reported in Foshan, a city adjacent to Liwan with a total of 1,997 cases, according to the commission.

The disease has been detected in 20 out of 21 prefecture-level cities in Guangdong.

Dengue is a mosquito-borne, potentially fatal disease that affects between 50 and 100 million people in tropical and subtropical regions every year, causing fever combined with muscle and joint aches.

Chen Jianhua, mayor of Guangzhou, urged at a seminar on Sunday to step up efforts in killing mosquitos. He also called for early detection of the epidemic, early medical treatment, and early quarantine so as to check the spread of dengue.

On Monday, the sixth day of China's week-long National Day holiday, Xinhua reporters saw vehicles spraying pesticide in the streets of Guangzhou. People were also disinfecting sewers, garages, channels and green belts in a bid to eradicate mosquitos. Residents could get free mosquito repellent at local communities.

As the holiday is drawing to an end, Guangzhou will launch a clean-up campaign on Tuesday, especially in schools and construction sites that remained unoccupied during the long holiday.

The outbreak of dengue this year is believed to be the worst in 20 years.

Health authorities attribute the outbreak to high temperatures and wet weather in Guangdong, where the mosquito population is five times the normal level.

Apart from Guangdong, some other southern provinces and regions also reported dengue cases lately, including Fujian, Hunan and Guangxi.