is there any chance for not getting infection

[moinresh2009]

Hi Dr. I wana aske one question, if A perosn had  unprotected sex with HIV positve person than 100% he will be infected or there is chance that he might not get infection ?
My question is in General? becz always I m reading this sentenses 10 out of 100 or 10 out of 1000 etc etc.plz explain

[Teak]

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[sam6386]

are those statistics of an HIV negative person? or positive?

[yarrak]

No, not every unprotected sex mean infection, although it's very risky. Unprotected vaginal transmission rate averages 1/2000 per exposure (more for receptive party, less for the insertive... duration of the intercourse, other pre-existing STD's and viral load of the infected partner are also important factors)but worth to remember that when all conditions and chances are together it does happen.

[Igotaboner]

I've read that even if the sex is unprotected, its not guaranteed you'll contract HIV