Vietnam detected nearly 20,000 dengue fever cases in the first half of this year, surging 54 percent over the same period last year, local newspaper Youth reported Wednesday.

Most of the cases were reported in the southern region, especially in Ho Chi Minh City, and the two provinces of Dong Thap and Soc Trang, where weather conditions and local people's habit of storing water in containers at their houses favor the breeding of mosquitoes -- the disease's transmitter, the paper quoted sources from the country's Health Ministry as saying.

In the six-month period, Ho Chi Minh City reported roughly 3, 000 cases of dengue fever infection, including two deaths, becoming the hardest-hit locality in the country.

The ministry is asking residents in localities nationwide to keep on cleaning environment around their accommodations, including keeping water containers clean and killing mosquitoes and their larvae.

Vietnam reported 49,400 cases of dengue fever infections, including 51 fatalities, last year, down 32.7 percent and 49.5 percent respectively from the previous year, according to the country's General Statistics Office.

Source: Xinhua