Influenza virus has daring capability to transform its shapes briskly and to covert in latest forms. Influenza vaccine spoils with in one to two years because during it this virus has alternated itself as far extent. Therefore old vaccine cannot compete it and a new vaccine is to organize for it.
Devastations of flu can be judged by this that from the beginning of twentieth century till now its five international plagues have been spread due to which two point five million deaths have occurred.
By the preparation of universal vaccine against influenza it will be no need to formulate influenza vaccine every year. Once this vaccine will have been developed then it will be not effective for existing and old but also for new forms coming in future.