Heidi Klum Heidi KlumSomebody hold her back.

Just what's up with Heidi Klum?

Well she's got an acute case of scarlet fever.

And it seems to have sent her a little crackers.

She isn't the only celeb to have come down with it, either.

Heidi and a whole host of stars took to the runway in the red.

It was all part of the Heart Truth's Red Dress Collection fashion show during Mercedes-Benz Fashion Week in New York.

And it was a cracker.

Check out Heidi and all the other glitzy lasses as they take to the catwalk in our gallery red frocks on the runway at MBFW.