Guangdong Province's dengue outbreak worsened over the weekend climbing from 8 infected to 78, said the provincial health bureau on Monday.

Five of the cases involved people from Indonesia, Cambodia, Malaysia and Thailand, but the others affected were all local residents.

Dengue is a serious infectious disease transmitted by mosquitoes. It kills 25,000 people and infects more than 100 million each year in tropical and subtropical regions worldwide, according to China's Ministry of Health.

Since the 1990s, dengue has broken out occasionally in Guangdong and neighboring Fujian Province, mostly on a small scale. However, large outbreaks occurred in Fujian in 1999 and in east Zhejiang Province in 2004.

To facilitate the disease's rapid detection and treatment, the ministry has announced a nationwide monitoring of dengue to gather details on epidemic conditions and its dissemination patterns.

Sixteen monitoring sites will be set up in the southern provinces of Guangdong, Fujian, Yunnan, Hainan and Guangxi Zhuang Autonomous Region.

(Xinhua News Agency August 29, 2006)