Question regarding new HIV vaccine

I haven't heard anything regarding the testing process for the new HIV vaccine the US Army was helping with. I've only heard the CNN version so far, but my question is this:

How are they able to determine exactly how many instances in which the vaccine prevented transmission of HIV in the test subject? Wouldn't they have to purposely expose the subject to potential infection to be sure?

And they did mention a control group as well. Does that mean that there were people exposed to HIV who had not received the vaccination?

If this thread is redundant, please redirect me. After a simple search, all I could find on the subject was a thread from months ago.

my assumption would be that they tested it with animals. and i also saw something about that and they made it very clear that it was just initial testing and that it was not a cure and it will be a while before its on the market.

reply to post by DeltaChaos


The new vaccine that they're talking about in the media now probably was tried on animals first. If you're talking about the same one or not or an older one I don't know.

I guess it takes six shots over a period of time and works about 37 percent of the time.

What I heard was they took two groups of people. All the people in both groups were considered high risk for contracting HIV due to their lifestyle and geographic locations.

One group was given the vaccine. The other was given a placebo that didn't do anything.

Over the course of a couple years they checked backed on the two groups and found the group that got the vaccine had about 40 percent fewer people contract HIV in comparison with the other group where the people had contracted HIV at the normal rate.

So they didn't expose anyone directly, but they just studied people they basically knew were going to get it on their own anyway.

[edit on 27-9-2009 by tinfoilman]