Expert: Terry B - 10/28/2008

Question
Hello i was wondering what the chances are of catching HIV from some one im not sure if they have HIV but i had unprotected sex with them what are the chances i could catch it from them ?? .....

Jack Male Age 16

Answer
Dear Jack:

Peace and thank you for writing.  The "chances" of your contracting HIV from someone through unprotected sex depends on a lot of factors, some of which you can control.  HIV - the virus that causes AIDS - is transmitted primarily through semen (the fluid in which sperm swims), blood or blood products, vaginal secretions (fluids produced by and in the vagina), and in breast milk.  

There is more virus (concentration) in the fluids of a person who is recently infected or in late stage disease, less in a person who is being effectively treated for HIV infection through medications.  Your risk increases generally by where you live - in some countries the rate of HIV infection is over 25% and in others much lower.  

The number of times you have sex (frequency) and the number of partners you have; how much of these fluids to which you are exposed (amount); whether you receive these fluids from another person into your body (receptive) or your contact is through your skin or mucous membranes (insertive); whether you or the other person have breaks in the skin or mucous membranes (other infections); how much area of your skin or mucous membranes is exposed (area); how long you are exposed to the fluids (duration), and; the means (route) of exposure - an exposure that breaks through the body's natural barriers to 'germs' (pathogens) such as an injection or direct fluid to blood contact is tremendously risky.  The problem with estimated "chances" is that it takes only one exposure to become infected.  

You can reduce your risk by taking control of your health.  Abstaining from fluid exchange is 100% effective; if you and your partner know your HIV status is negative (only known through appropriate blood test) and don't exchange fluids outside the relationship, you are also protected.  If you don't abstain (and it appears you haven't in the past) and you don't have that level of relationship with someone, you should carry a condom even if you don't plan on using it.  A condom reduces the amount of fluids to which you are exposed or to which you expose your partner; it provides additional protection and reduces the area exposed to the fluids; properly used it is effective in preventing transmission.

I would recommend you to to www.avert.org and/or www.thebody.com and read up more generally about HIV and how to reduce your risk while still enjoying life.  And I would recommend to find a voluntary counseling and testing site near you to talk with a counselor and be tested.  Though your risk thus far (one possible exposure) is low, it is helpful to talk one-on-one with a counselor and know your status for sure.

Best to you and yours,

Terry