Yahoo pin

A conversation ensued between a couple after watching an advert on TV.
Woman: Honey this HIV thing is really real, you know.
Man: Sure it is.
Woman: You might want to avoid sharing sharp and unsterilised objects like your blackberry pin
Man: 'Oh that!', apparently lost to what his wife meant.
Woman: 'Yes', the woman reemphasised.
The man answered his companion with the intention of  putting her mind at rest,and stressing how safety conscious he is. He said: 'In fact, i don't share my pin at all, no matter how close. Neither do i take from others. I only give them my Yahoo pin because that is constantly soaked in antivirus like Dettol.