<prompt> Dengue fever is characterized by all exceptRashFeverThrombocytopeniaIncreased clotting time  <response>: Ans. d Increased clotting time. Ref. Harrison, Medicine, 18thTable. 17-1DENGUE HAEMORRHAGIC FEVER Vector of transmission is Aedes aegypti. Acute onset with fever, arthralgia, headache, adenopathy, conjunctival injection and bradycardia. Continuous saddle back fever with break on 4th5th day. Morbilliform rash--3 to 5 days, centrifugal spread. Hemorrhagic form of dengue fever is characterized by thrombocytopenia, hemoconcentration, hypotension and fever. AI2005.Dengue fever caused by Dengue virus 4 serotypes; flavivirusesRash in 50 of cases; initially diffuse flushing; midway through illness, onset of maculopapular rash, which begins on trunk and spreads centrifugally to extremities and face; pruritus, hyperesthesia in some cases; after defervescence, petechiae on extremities in some casesHeadache, musculoskeletal pain breakbone fever; leukopenia; occasionally biphasic saddleback fever. 