A study conducted at a Dhaka laboratory has found that three out of every four dengue patients got infected with the DENV-2 type, the most severe of all dengue virus types.

In addition to fever, DENV-2 can cause two or more other symptoms of typical dengue infection and can be fatal, say physicians.

Dengue infections are caused by four closely related viruses -- DENV-1, DENV-2, DENV-3, and DENV-4.

These four viruses are called serotypes because each of them has different interactions with the antibodies in human blood serum, according to Nature science journal.

To know about the most circulated dengue serotypes in Dhaka, virologists at the National Institute of Laboratory Medicine and Referral Centre (NILMRC) tested 200 samples recently.

In the study, DENV-2 serotype was detected in 151 samples, DENV-3 in 37, and both DENV-2 and DenV-3 in 12, according to a press release of NILMRC.

The institute is also preparing to start dengue genome sequencing soon, read the press release.

"Genome sequencing is urgent to identify any potential changes in the dengue virus gene, which will help the authorities take actions accordingly," Dr Arifa Akram, assistant professor at the Department of Virology at NILMRC, told The Daily Star today.

In June, the Institute of Epidemiology, Disease Control and Reserach (IEDCR) also found DENV-2 as the most prevalent serotypes after testing 40 samples.