Gosh, I don't think it's that easy to get. You do have to be close to someone who actively has wc. I was exposed to three cousins all at the same time, with wc and I didn't get it. Funny.
Anyway, I would get sodium ascorbate (Vita C) at home plus pulsatilla a homeopathic remedy.
The SA (sodium ascorbate) works really well. You probably have to order it on line from a vitamin shop.