Terrific photograph. The title is the right sentiment but too long for a billboard. "Who's had their flu shot?" or something like it, would work better. Also a bit hard to figure out where the words would go on the billboard. However, I have not marked this excellent entry down for that, because this is about the image, and yours is very good. 8
I really like the idea behind this. I think it is the most imaginitive in the challenge. I think you could have made the open window more blue in post processing, just to make it stand out even more. Advertising is about punch. Best of luck.
I don't see a connection with your message and your image sitting here looking at it. (Don't slam me, I understand 1 in 10...) I'm sure that the message won't get through at 65 miles an hour either...
TC
ok, i am voting this challenge in 2 passes. in this pass, you will get a partial comment and a score. then i will come back to comment again. if you have any problem whatsoever with this comment, pm me and let me know. otherwise, take it with a grain of salt...i'm not trying to be a know-it-all, i'm just explaining where i'm coming from in voting this challenge. and, if this comment is NOT helpful (of if you think i'm full of $#!+), don't mark it helpful.
billboards are a science unto themselves. a lot of research has gone into determining just how much information a person can digest and retain in specific time spans. they use this information to develop formulas for determining the number of words and letters to use on billboards, as well as their sizes. they also determine the size and number of visual elements to include.
the graphics/photograph on a billboard are designed to get the point across in a moment. on the road, a driver will have less time with a billboard than a voter will give your image. this is a key element in the challenge: composing a shot that will get its point across quickly and succintly. along those lines, a strong composition will probably have few details and make strong use of negative space.