Two people have died of the disease so far, although it is the dry season in the south and Ho Chi Minh City, normally not the peak transmission time for dengue fever.
Dengue occurs all year round in Vietnam, but peak transmission falls during the rainy season, April through October in the north, and June through December in the south.
Doctors at local hospitals say that because it is not the usual season for dengue fever, most patients do not pay much attention to checking their health even after getting symptoms of the disease.
Doctor Nguyen Thanh Phong with the city’s Tropical Disease Hospital said that with the number of dengue cases staying high, the situation was "quite abnormal." He advised residents not to neglect their health at this time.
Most patients admitted to his hospital for dengue fever are adults who have not tested themselves soon enough, Phong told the Tuoi Tre newspaper.
In the first nine months of last year, Vietnam recorded more than 64,000 cases of dengue fever, including 11 deaths. Corresponding figures for 2017 were 183,287 and 30 respectively.