|MadSci Network: Virology|
A study published in the scientific journal AIDS in december of 1996 reported that in a cross-sectional study of the levels of HIV viral load in body fluids (plama, semen and saliva) of 26 seropositive patients, the median levels of HIV-1 RNA copies in plasma was 14,817/ml (range: 167 - 254,880), in semen was 515/ml (range: 0 - 196,050) and in saliva was 162/ml (range: 0 - 72,080). This study thus tell us that there is approximatively 100 times less HIV in saliva than in plasma so that there would be less HIV in 1 liter of saliva than in 10ml of blood.
BUT! There is a difference between the amount of infectious virus and just the number of copies of HIV-1 RNA (ie: the genetic material of HIV). In fact, many reports have demonstrated that the low level of salts (hypotonicity) in the saliva as well as the exposure to high levels of oxygen in the mouth have a very potent inhibitory effect towards HIV.
So not only does the virus load is very low in saliva, it is probably not infectious. BUT! It must be stated that deep kissing could lead to transmission of HIV in the case of an individual with a high viral load AND injuries or scratches in the mouth. So deep kissing with an unmedicated infected individual who does not take care of it's buccal health is not recommended... Seriously, the important thing to remember is that BLOOD is the issue in that case, not saliva. Also notice that the HIV viral load in semen is pretty low but HIV IS infectious so that both free virions and infected macrophages in the semen can lead to HIV transmission following unprotected intercourse.
A risk analysis done in the journal of acquired immune deficiency sydrome in April of 1993 reported that there was 20 times less risk of acquiring HIV from a bite of an infected individual than by a needle stick (0.3 to 0.5%).
I hope these facts answered your question... altough I didn't really answer it.
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