Need Clarification

[thankuverymuch123]

Dear Dr. Handsfield,

Thank you for your advice.
I am not sure if you remember me. The link below could help.
http://www.medhelp.org/posts/HIV---Prevention/Which-test-include-all-types-and-subtypes-of-HIV/show/1825334

Now I am the friend!!
Thanks God and as you predicted I return with 8 weeks and 3 months test results both negative with a 4th generation test.
A little concern is about the "exceedingly rare" subtypes which by your comment I comprehend could not be detected by 4th generation test and could be detected by PCR RNA.

If you could kindly answer my question in this regard, I would appreciate much.
Why I do not need a PCR RNA while I know that some subtype could be detected by that and could not be detected by the 4th generation test? Dont I lose something by not testing by PCR?

Your words in this regard could bring me peace.

Thank You.

[Edward W Hook, MD]

You are being paranoid and reading meanings that are not intended into Dr. Handsfield's comment.  Relax.  You did not get HIV and need to move on without further paranoid thinking.  EWH

[thankuverymuch123]

Dear Dr. Hook,

Thank you for your understandable description.
I am familiar with the concept of no zero in real world but the sentence of Dr. Handsfield meant something else. Please take a look again:

"The exceedingly rare exceptions can be detected by a PCR test for HIV RNA, but I believe such testing is not necessary in Thailand."

This means that he is speaking about some specific subtype which must be considered somewhere else but not in Thailand.

If you could verify this once more with him and confirm that he does not mean any special subtype, I would appreciate.

Thank you very much.

[Edward W Hook, MD]

Welcome back to our Forum. today I will be answering your questions.  Dr. Handsfield and I share the forum.  You got me.  FYI, the reason we share the forum is because we have worked together for nearly 30 years and while our verbiage styles vary, we have never disagreed on management strategies or advice to clients.

I think your lingering concerns represent a misunderstanding of how scientific data is explained and of your risk.  As Dr. Handsfield told you, based on the results you had earlier, there was virtually no risk that you had acquired HIV through your exposure to a Thai CSW.  Since then your repeat tests prove this.  

As far as why Dr. Handsfield said "exceedingly rare" it is important for both you and other readers, you must realize that we VERY frequently get questions asking if different types of exposures or prevention measures are 100% effective.  The answer to that is that this is scientifically impossible.  For a variety of mathematical reasons far too complex to go into here, all one can do with well conducted scientific studies is estimate probabilities.  By definition, any estimate, cannot ever be 100% certain because of the incredibly low possibility that someone will get HIV through a previously undescribed mechanism tomorrow.  On the other hand, when Dr. Handsfield or I say that something is exceedingly rare, virtually zero, very close to no risk, or of minimal risk, or use any other term to indicate a very small risk, that means "close to zero" in a world where zero cannot be attained.  You need not worry that you loose any meaningful likelyhood of detection by not wasting your money paying for PCR testing.  

Put another way, I cannot give you are 100% promise that you will not be struck by a satellite falling from the sky before you finish reading my response but it is "exceedingly rare".  Just as I hope you will not worry about falling satellites, you should not be worried about HIV from the exposure that you described.  EWH