Update a bean object of one page as a result of change in other screen

I have a web application with 4-5 screens. Currently a bean object is getting populated by querying the DB at the start up. Now I have a add variable functionality which can be done in two screens. If I add a variable in screen 1 and go to screen 2 the variable I added in screen one is not seen, simply because the bean object is not getting updated. Now one solution could be to read into the bean object every time I navigate to the screen . This I think is not the right way. Is there any other way wherein if there is a change in screen1 we can signal the other screen objects to update themselves or vice versa ?

Thanks, Sahana