<prompt> All are true regarding dengue fever except:Common in south Asian regionSubclinical cases are not seenTransmitted by Aedes aegyptiThrombocytopenia  <response>: Ans: b Subclinical cases are not seenRef: Park 19 ed, p. 206,207Dengue virus is an arbovirus, vector being Aedes aegypti and Aedes albopictus with 4 serotypes:Epidemiology of dengue fever:About 1.3 billion people are living in dengue endemic areas. By 1997, most of the countries of SouthEast Asian Region have experienced large outbreaks of the disease. Over the past 10-15 years, next to diarrhoeal disease and acute respiratory disease, dengue has become a leading cause of hospitalization and deaths among children in SEAR.Countries in SEAR have been divided into 4 categories based on prevalence of the disease.Cat A: Major health problemCat B: Emerging disease with cyclical epidemics India falls this categoryCat C: Endemicity uncertainCat D: Non endemicCriteria for clinical diagnosis of DHF:1 High grade continous fever lasting for 2- 7 days2 Hemorrhagic manifestations including atleast a positive tourniquet test.3 HepatomegalyLab diagnosis1 Thrombocytopenia 100,000Mm3 or less2 Hemoconcentration: Hematocrit increased by 20Dengue shock syndromeDSS1 All the above criteria plus shock manifested by rapid and weak pulse and narrowing of pulse pressure or hypotension with cold clammy skinManagement::Symptomatic and supportive 