After years of fighting, AIDS prevention advocates have won two major but little-noticed victories - one in Harrisburg, the other in Washington - that experts say should reduce the transmission of diseases spread by drug addicts.

The omnibus appropriations bill that President Obama signed last week drops a long-standing ban on federal funding of needle exchange programs. And the Pennsylvania State Board of Pharmacy three months ago lifted the requirement for a prescription to buy syringes at a pharmacy, leaving New Jersey and Delaware as the only states still requiring a script.

Both actions had been delayed for years over fears that they could increase crime, despite mounting evidence that easing access to sterile syringes reduces transmission of HIV and hepatitis C without increasing drug addiction.

That can seem counterintuitive. But dirty needles are a leading source of HIV infection, and people in the field say so-called structural changes often are more effective than trying to change an addict's behavior. Philadelphia has ample reasons to participate; its HIV rate is three times New York City's, and is high even for a metro area.

Needle-exchange programs, in which addicts turn in used syringes and get new ones in return with no questions asked, have been highly successful worldwide. "The number-one thing you should be doing is making sure people have access to clean needles," said Roseanne Scotti, director of the Drug Policy Alliance of New Jersey,

"Addicts are not stupid people. If they are able without too much hassle to keep themselves disease-free, they will do that," said Harvey Weiner, an addiction counselor and program manager around the region for 35 years.

If prescriptions had not been required when she was shooting up several ago, one former addict said, "I definitely would have made an effort to get a clean syringe."

Now a full-time college student and a counselor at a suburban treatment center, the 29-year-old woman, who discussed her history on the condition that she not be identified, recalled searching for clean needles to buy from friends, dealers, and people on the street for a dollar or two. She used the needle-exchange program.

At the height of her addiction, homeless and desperate for a fix, she would find needles lying around houses where addicts shot up. She knew the risks.

"But when you are under the influence, you don't make good choices. To overcome the sickness, the withdrawal, I was OK with that," she said.

She had snorted at first but switched to injecting to save money - $20 to $30 a day, instead of $60 to $70, as the opiate went more efficiently into the bloodstream. She got a new needle perhaps every other day and would use it for 10 or 20 sticks, the tip becoming duller each time.

"I had abscesses all over my body," she said. "My abdomen, my hips, my thighs, my back." She sought treatment in 2005 and said she has been sober ever since. "Thank God I only walked away with hepatitis C."

Hepatitis C is a usually chronic and sometimes fatal disease spread mainly through dirty needles, and more easily than HIV. More than three million people in the United States are infected, and they come from all walks of life.

"The typical drug user is employed, is more likely to live in suburbs [than] in the city, and is as likely to be white as black," said Scott Burris, a Temple University law professor and an authority on syringe regulation and HIV.

About 424,000 Americans a year over age 12 inject illegal drugs, the Substance Abuse and Mental Health Services Administration reported in 2007, the most recent data available.

Pennsylvania has only two needle-exchange programs, in Philadelphia and Pittsburgh. So Burris said he believes that the new regulation allowing pharmacies to sell syringes without a prescription will make the most difference in suburban areas and the state's vast rural middle.

The rule, which took effect Sept. 12, simply allows pharmacists to sell syringes without a prescription. There is no limit on age or number. Syringes still must be kept behind the counter, however, and the regulation does not require that they be sold. Major drugstore chains, however, said they had moved quickly to comply with the new rule.

The ban had been in place since 1973, when recreational drugs were a big concern and governments sought to crack down on head shops by prohibiting drug paraphernalia.

The AIDS epidemic began a decade later. Injection drug use soon was identified as a major source of HIV transmission, although the size of its role has varied over the years as patterns of drug use changed. Advocates say that needle-exchange programs, now about 200 nationally, also made a difference.

One study compared injection-drug users in Newark, N.J., where needles were not then available at an exchange or in pharmacies without a prescription, with those in New York City, where both were permitted, between 2002 and 2004. Rates of HIV were 26 percent in Newark vs. 5 percent in New York; hepatitis B, 70 percent vs. 27 percent; and hepatitis C, 82 percent vs. 53 percent, the researchers wrote last year in the Journal of Urban Health.

Other research has found even less litter and reductions in accidental needle-stick injuries among police (presumably because needle-exchange programs make a point of scouring the area). A National Institutes of Health panel endorsed improving access to syringes in 1997.

By the time the Pennsylvania State Board of Pharmacy published its final proposed regulation last summer, there were no negative comments.

In New Jersey, bills that would make a similar change have passed the Assembly twice but got stuck in the Senate. Scotti of the Drug Policy Alliance notes that legislators approved pilot programs for needle exchanges in 2006, including one operating in Camden. She says that legislators did not want to change too much too fast and that she hopes a bill will pass next year.

In Washington, the new budget for fiscal 2010 for the first time lacks a rider that had been attached for years banning federal funding of needle exchanges.

The change adds no money for needle exchanges; such programs will now be able to apply for funding from the AIDS-prevention pie, most of which comes from the federal government.

Nor does it change state laws. Needle exchanges remain banned in Pennsylvania, where then-Mayor Edward G. Rendell in 1992 issued an executive order allowing one in Philadelphia to combat a public health emergency caused by AIDS, and in New Jersey, where six pilot programs are authorized, and four are operating.

"It means that there is a change in public opinion," said Jose Benitez, executive director of Prevention Point Philadelphia, the city's needle exchange.

He says he hopes federal funds might replace some of the $343,000 in city money that currently pays for six locations, five of them serviced by a van, on different days. That might allow an expansion to three more sites that have high rates of HIV and hepatitis C.

Last week in the Mantua section, Yaya Liem stood in the door of the retrofitted Coachman and chatted with a man who had wandered by, asking about legal services.

Did he need help applying for an ID? Training for how to respond to an overdose? Liem, the coordinator of the exchange program, could could test him for hepatitis C, but results would take two weeks.

The 1.6 million needles that are exchanged each year, Liem said earlier, are "sort of our first line" of contact with the most hard-core, least-trusting addicts who are often in the worst shape.

That day, one addict exchanged 350 dirty needles for clean ones, another did 50, a third 400 (for eight people, he said), a fourth got 10 needles plus condoms. One or two diabetics made exchanges, too. It was a slow two hours, about 15 people in all.

Liem told many of them about the relaxation of pharmacy rules, adding in the results of an informal survey: Rite-Aid charges more ($6.90 for a BD-brand 10-pack, although the store brand may cost as little as $16.99 for 100), CVS less, "some pharmacists give no problem," but "other places say no."

A decade ago, when Karen Day left Oregon to care for her elderly mother in Havertown, the longtime addict was surprised to find that she could not buy syringes in pharmacies here. She exchanges about 300 needles a month.

Most are for the mix of Ritalin and Dilaudid that she cooks up and injects 10 to 20 times a day. The rest are for her 8-year-old chocolate-colored labrador, a diabetic.

"The only way I have coped with anything my entire life has been the drugs," said Day, 48. She has never shared a needle, she said. "I try to be as smart as I can about the idiotic things that I do."