posted on Apr, 29 2010 @ 08:01 PM
reply to post by hautmess
They can't use it because HIV is an obligate intracellular organism, being a virus. For the large majority of it's life, it is inside the CD4 cells
of the host's immune system. The biocides in saliva are released by non-specific immune cells, meaning they can't be primed to specifically attack
HIV or HIV-infected cells. Most of them are anti-bacterial, as there are no instances of bacteria needing to be saved, not even our commensal bacteria
(they are integral to our health, obviously, but find other ways to evade the immune system).
The main reason HIV and other viruses can't commonly be spread via saliva is a matter of migration. There is little to no way for HIV particles or
HIV infected cells to find their way to your salivary glands. Of course, you'll have the stray infected CD4 cell that migrates there during an immune
response, if you have an infection in your salivary or parotid glands, but the number or viral particles needed to transmit an infection is rarely, if
ever, present in saliva.
Viruses and bacteria that DO target the cells of salivary glands, though, can of course be transmitted by saliva. A good example is mononucleosis,
which is called "the kissing disease" for obvious reasons.