Bringing the total number of confirmed dengue cases to over 1,400 till September 30 this year, over 800 fresh cases were reported in Bangladesh capital Dhaka and the outskirts of the city over the last month.
The figure reported by the Institute of Epidemiology, Disease Control and Research (IEDCR) paints an alarming picture as the capital city has seen a rapid surge in the incidence of the mosquito-borne viral infection.
A total of 375 and 1,749 cases of dengue were reported in 2014 and 2013 respectively.
But there were no reports about casualties from dengue in 2013 and 2014.
"The number of cases reported so far in 2015 is the highest in the last nine years," an IEDCR official said.
"We have a lot of reasons to be worried as four people have already died this year," the official who preferred to be unnamed, said.
Dengue is transmitted by several species of mosquito within the genus Aedes.
The first case of mosquito-borne viral infection was reported in Bangladesh in 2000, and at least 100 people died from the disease between 2000-2003.
The IEDCR official said Bangladesh is now well prepared with enough trained doctors to handle the disease.
He stressed the need for cleanliness as part of the preventive measures to destroy breeding species of mosquito.