Is anyone familiar with the Needle Exchange Program? I need to know why it helps reduce HIV in drug users...?

Doing a reserach paper and the question/ topic is Does the implentation of the Needle exchange Program help reduce the spread of HIV in injection drug users of the US... Any bit of info will help plz

Someone addicted to heroin for example WILL use a needle to get their drug. It doesn't matter where that needle comes from, old insulin syringe, reuse the same one a number of times, etc. People can share needles, two people doing heroin together. If one has HIV they can easily give it to the other.
With an exchange program, a person gets a known clean needle, thus drastically reducing the potential to transmit disease like HIV in that manner.
It might sound like a bad thing to subsidize one's drug habit, and it is. But compared to the burden placed on the healthcare system for these diseases, it can prove to be a better use of our money. The taxpayers, and people's insurance premiums, and healthcare costs, all reflect money spent to provide an uninsured AIDS patient with care for example. So it would be best to prevent that infection in the first place.

It also helps because a person might contract disease from sexual intercourse with someone that used drugs, and such. So it even effects non-drug users.

Another reason to end the drug war. We could seriously reduce the spread of hepatitis and HIV, and the drugs could be screened for purity and dosage, so fewer would become sick from contamination, and fewer cases of overdose.

Yes it does.. The way I understand it, doctors and other medical professionals give steralized needles to drug users and the users give the used needles to the professionals to dispose of properly. This helps prevent the sharing of needles and the re-use of needles, both common causes of spreading HIV and Hep.