I love this. Just love it. Short, simple, and to the point.
This was a billboard designed by Every Child By Two, a vaccination advocacy group I like a lot and strongly support (in fact, if you buy a Zen Pencils print of my Science Fare speech half the profits go to ECBT). While people like Meryl Dorey and Judy Wilyman vilely attack parents of babies who have died from vaccine-preventable diseases, groups like ECBT are trying valiantly to save babies' lives.
Go talk to your board certified doctor and find out if you need to be vaccinated, and if you need your TDAP booster. Help save lives.