Dengue, a viral infection spread by the infamous Aedesaegypti mosquito, is the fastest growing mosquito-bornedisease in the world today. It is now a major internatioinalpublic health concerns. Over the past three decades therehas been dramatic global increase in the frequency ofdengue fever, dengue haemorhagic fever and dengue shocksyndrome and their epidemics. It is found in tropical andsubtropical regions around the world. Some 2.5 billionpeople i.e two fifth of the world's population in tropical andsubtropical countries are at risk of the disease. Anestimated 50 million dengue infection occurs worldwideannually and about 500,000 people with denguehaemorrhagic fever require hospitalization each year.Approximately 90 per cent of them are children aged lessthan five years, and about 2.5 per cent of those affected die.During epidemics, infection rate among those who havenot been previously exposed to the virus are often 40 to 50per cent, but can also reach 80 to 90 per cent.