At least 63 locally contracted cases of dengue fever have been reported in the city of Zhongshan in south China's Guangdong Province, local authorities said on Monday. The cases have been reported in Huangpu Township since July 16 and more cases may be reported soon, Xinhua quoted a statement from the provincial health department as saying. All of the patients have been hospitalized. None of them have recently traveled to Southeast Asia, where most infections occur, indicating that the outbreak is not imported, it said. 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 mosquitoes that transmit it.