New Delhi:As many as 247 people died due to dengue in India last year. Latest data on the disease prevalence released by the health ministry also shows a significant rise in the incidence of dengue — from 18,860 cases in year 2011 to 49,606 in 2012. About 1,700 dengue cases were reported from Delhi and four people died due to the disease last year.

Scientists say dengue is becoming hyper-endemic — a term used when different strains circulate together or coexist. This means that a person who has got infected with one kind of virus can still get infected by another serotype because he is not exposed to it; thus causing more cases.