HIV Transmission question

I am not posting this question to question my "no risk" encounter. I just want to help ease my anxiety by learning about how HIV transmission could take place in oral sex.

I understand that HIV is transmitted from one person to another through either blood, semen, pre-cum or through mother's milk to baby.

Since my anxiety is specifically in insertive oral sex, I want to understand why it is a no risk situation. So for the insertive partner to be infected, there first needs to be blood in the giver's mouth and there needs to be enough blood so that the saliva is not able to neutralize it in time before it gets to the urethra. Now if blood gets to the penis opening, what else has to happen for transmission to complete? Does there need to be blood with virus still intact only and that virus gets soaked into the opening's membrane?
And how much blood would be needed in order for this kind of transmission to occur?
Also, what if the giver has very little saliva and is not able to neutralize the virus? How much saliva is needed to keep the act "safe"?

[joggen]

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[madeabigmistake]

Dear medhelp admins, I am not questioning a no-risk situation at all. I am just trying to understand the mechanics of how transmission could theoretically could take place. For the sake of the forum rules, I accept that oral sex is a no-risk situation and I am not trying to question that. I want to understand the details of the mechanics of transmission, even hypothetical so that I can understand how impossible it really is.

[joggen]

If you accepted that it wasn't a risk you'd be doing something other than posting questions about it.

If you really need to know more, read Nursegirl's journal.

[tonster246]

Saliva inhibits the transmission of HIV...oral sex carries the lowest risk of HIV transmission and is more of a theoretical risk than an actual one..this is due to the ultra conservative fear based education and knowledge that we are receiving these days..if oral sex was a genuine risk a lot of people would get HIV.. The doctors in the medical forum would tell you that the odds are 1 in 10000 and it means you could possibly get struck by lightning than contract HIV from oral sex and that too from a single exposure!! It just doesn't happen!

[nursegirl6572]

http://www.medhelp.org/health_pages/HIV/HIV-AND-ORAL-SEX-THE-FACTS/show/1278?cid=68