Will i get infected with non-infected person by oral sex?

I was just wondering that will i get infected with any virus when i have oral sex with a non-infected person? is there any risk?

 

Non-infected means he/she doesn't have a virus, so the answer is no. My question is how do you know he/she isn't infected? You can only really be certain from a pathology test and even then there are margins of error.

 

Because she does not have any history about sex ?

 

You could still catch Herpes from someone who's never had sex. Herpes can be transmitted from sharing straws and things like that. There's still many germs that are shared, although if she indeed has no sexual history then you are at least safe from the classic big STDs like Syphillis.