Solution:Dengue virus (DENV) is the cause of dengue fever. It is a mosquito-borne single positive-stranded RNA virus of the family Flaviviridae; genus Flavivirus. This virus causes bone marrow suppression leading to reduction in number of blood platelets. A typical person has a platelet count of between 150,000and 250,000 per microlitre ofblood. About
80 to 90 per cent of patients with dengue will have levels below 100,000, while 10 to 20 per cent of patients will see critically low levels of 20,000 or less.