Here's how to make the H1N1 costume:
For the syringe, find a plastic trash can large enough to slide over your head and shoulders.
Remove the bottom and cut two holes in the side for your arms.
Cover the can with white paper and make syringe gradations with black tape or a marker.
Add a bottom rim made of poster board or construction paper.
For the needle, stick a dowel into the narrow end of a funnel.
Attach string that can be tied under your chin as with a hat.