Likelihood of gettings AIDS from needle stab

[El Zagna]

Over in the Pit (3rd grader sticks 19 with needle...one tests positive for HIV)they are discussing the hysteria of contracting AIDS from a diabetes test needle. That got me to wondering just how great the likelihood really is of getting infected from an accidental needle puncture, vs, say, unprotected sex with an infected partner. There is one thread that discusses it, (Important Question re: HIV infectability ) but it's pretty old.

I assume it's one of those probability things where if you get a single HIV virus you have a chance - albeit tiny - of contracting AIDS, if you get two viruses the probability goes up and if you get a whole syringe full of the virus you have a chance - albeit small of NOT contracting AIDS.

Does anyone have any better numbers than this?

[KarlGauss]

The figure usually given is 1 in 300 for contracting HIV after a needle-stick or similar exposure. (Reference)

[aerodave]

None of the news stories I've seen have been very good at describing exactly what the "weapon" actually is. The AP stories all use the word "needle" pretty ignorantly.

A diabetes testing lancet has a little push-pin sized point that pierces the skin by a fraction of an inch. It withdraws so quickly after breaking the skin (probably on the order of a couple hundredths of a second) that there's very little opportunity for blood to get on it. In fact, blood usually doesn't even start appearing from the hole for a good second.

I'm not saying the kid was using it as intended, although that's pretty likely. The reason she did it was probably just a fascination with the spring-loaded actuation of the device.

Even so, I'm not saying that using it properly totally eliminates the possibly of virus transmission. But it's important to make a distinction between a device like this and some Psycho-esque attack with a blood-dripping hypodermic needle.