At least 63 locally contracted cases of dengue fever have been reported in the city of Zhongshan in south China's Guangdong Province and health officials have warned of more cases.
The cases have been reported in Huangpu Township since July 16 and more may be reported soon, according to a statement from the provincial health department.
All of the patients have been hospitalised.
None of them have recently travelled to Southeast Asia, where most infections occur, indicating that the outbreak is not imported, state-run Xinhua news agency reported.
Experts have attributed the outbreak to rainy weather that has resulted in greater numbers of mosquitoes.
The number of infections of the potentially fatal, mosquito-borne disease has been rising year-on-year.
Experts have called for controlling the Aedes aegypti mosquito that transmits the disease.
