Dengue remains one of those diseases that seem to rear its ugly head every monsoon and affects people all over the country. Even cities like Delhi Kolkata Mumbai and Chennai has more than its share of dengue cases. So what is dengue? It is a tropical disease usually transmitted by mosquitoes and the common symptoms include fever headache muscle and joint pains and skin rash. There is no vaccine for dengue and the only way to reduce infections is to improve hygiene levels so as to prevent mosquito-bites and prevent mosquitoes from breeding. It's particularly difficult to create a vaccine