China's Health Ministry issued an alert on Tuesday for dengue fever, a potentially fatal, mosquito-borne disease, as the peak season continues in south China.

"Health departments at all levels must closely monitor the dengue fever outbreaks and strengthen detection to make sure that all prevention measures are properly carried out," Mao Qun'an, the ministry's spokesman said at a press conference.

He warned that south China is still at the peak season for dengue fever outbreaks as the average temperature of 28 degrees is prime mosquito breeding weather.

Mao called for great public effort to eradicate mosquitoes by cleaning up the environment.

China reported 502 dengue cases in September but no one has died from the disease. Most of the cases occurred in south China's Guangdong Province, where 492 cases have been reported Sporadic cases occurred in other provinces but they were mainly brought by people traveling from south China.

Dengue causes severe fever and can lead to vomiting, nausea and body rash. It can cause severe pain in the joints. Also called bone-breaker's disease, some dengue strains cause internal bleeding and death.

A larger outbreak sickened more than 1,000 people in Guangzhou in 2002 but caused no fatalities.