Dengue fever, a potentially fatal, mosquito-borne disease, will be on the minds of many Guangdong residents in the coming months, after a large number of cases were reported in July, said an expert with the provincial center for disease control and prevention.

Eighty-five cases had been reported in July by Monday, although none of them were serious, according to the provincial health department.

The figure represents a big jump from seven in the same month last year, with just three in July 2011 and one in July 2010.

Over the same three-year period, though, October has proved the worst month, with 185 cases in 2012, 22 in 2011 and 66 in 2010.

"Dengue fever occurs mainly between July and November in Guangdong," said He Jianfeng, an expert from the disease control and prevention center.

"Some Southeast Asian countries, including Thailand, Vietnam and Malaysia, have had worse outbreaks this year. It is the rainy weather since late June and the subtropical summer temperatures in Guangdong that have helped mosquitoes to breed in large numbers."

Of those cases reported in the southern province this month, 63 were in the city of Zhongshan. Another 22 cases struck in eight cities, including Shenzhen, Zhuhai and Guangzhou, and mainly affected people who had traveled outside China.

The discovery of cases contracted locally is often an indication that the number of cases is likely to grow, the health department said.

The department issued emergency notices in the province’s cities on Monday, urging rigorous enforcement of mosquito control methods, such as the draining of stagnant water in homes. The disease control center has also sent professional teams to spray pesticides in public area.

"The disease is spread by Aedes albopictus, also known as the tiger mosquito, which is common in Guangdong and present to varying degrees in most parts of China," He said.

It favors clear water, such as that found in vases, aquariums and plant pot trays, and tends to bite humans during the day.

The symptoms of dengue fever include aching bones, pain in eye sockets, a reddish face, fever and significant reductions in white blood cells. The disease is often misdiagnosed as a blood disease.

Patients are treated in mosquito-free wards for five to seven days before they are transferred to general wards.

The health department in Guangdong makes clear that the disease is both preventable and curable and adds that the main way to prevent infections is to control mosquito populations.

No fatal cases of dengue fever have been reported in Guangdong in the past two decades, He said.

The expert advises tourists to Southeast Asia to take preventative measures, such as wearing a long-sleeve shirt and using mosquito repellent.