A program here to give intravenous drug users new needles for old ones is helping to curb the spread of the AIDS virus, a new study says.
The study, released today by Yale University researchers and the New Haven Health Department, estimates that the eight-month-old needle-exchange program has reduced new infections with HIV, the virus that causes AIDS, by 33 percent among participants. The sharing of contaminated needles is the major way that the virus is transmitted in New Haven, New York City and other urban areas.
The project used a novel method to measure new infections: it tested the needles for HIV contamination.
The results of the study seem likely to add heat to the debate over whether needle-exchange programs that are intended to prevent AIDS encourage another ill -- drug use. This argument was made by the administration of Mayor David N. Dinkins when New York City scrapped a similar program last year.
While emphasizing that their study sample was small and the results preliminary, New Haven officials hailed the results as evidence that the programs work.
"This program is not a solution to AIDS or to drug addiction," Mayor John C. Daniels said. "It is one more Band-Aid, but it is a Band-Aid we cannot afford to do without."
At a news conference, Mr. Daniels, Police Chief Nicholas Pastore and state and city health officials released an evaluation of the program, whose key component was the tracking of syringe needles given to addicts.
Edward H. Kaplan, an associate professor at Yale University's School of Medicine and also its School of Organization and Management, devised the tracking system, in which a number was assigned to each fresh needle and the person receiving it was identified by a code name. Program workers also recorded the date and site of the exchange.
Infection Went Down
The system, he said, allowed researchers to determine whether the person who got the needle returned the same one -- or whether someone else returned it and sharing likely occurred.
By testing the needles for the presence of HIV, researchers were also able to estimate the prevalence of the virus and the incidence of new infections among participants.
In one sample of 741 needles returned between last November and March, the researchers found that 44.5 percent that were not shared tested positive for the virus, compared with 52.8 percent for those that were shared and 67.5 percent for those that originated elsewhere.
But as the program continued, the researchers found that HIV infection went down: 63 percent of the shared needles were infected in November, 51 percent in January and 26 percent in March, although Professor Kaplan said the number of tests for the most recent period was small and the figure less reliable.
The drop, he said, indicated that the needle-exchange program was having an effect by replacing the number of infected needles in circulation. The 33 percent reduction in new infections was an estimate using a mathematical model, he said.
"If you replace the needle, you're reducing the length of time the needle is in circulation," Professor Kaplan said. "It is by reducing the prevalence of HIV in circulating syringes that the incidence of new infections can be reduced."
Dr. Don C. Des Jarlais, a member of the Federal Commission on AIDS and director of research at the Chemical Dependency Institute at Beth Israel Medical Center in New York City, said the New Haven findings were consistent with other studies in the United States, Europe and Australia. But he called the testing of syringes, Professor Kaplan's method to detect reduced HIV transmission, "an important advance over self-reported behavior."
Sale of Needles Outlawed
Needle-exchange programs have been at the center of a debate over how to prevent AIDS among drug users. They become infected by sharing needles and can then transmit the virus through sex and pregnancy.
Eleven states, including New York and Connecticut, outlaw the sale or possession of hypodermic needles without a prescription, and advocates of people with AIDS have repeatedly been arrested for openly defying the law by distributing clean needles. The New Haven program was authorized by special state legislation.
The advocates argue that they are saving lives and have won acquittals in court, including a case in New York City in June in which a Manhattan judge ruled that eight members of Act-Up had been justified in trying to distribute clean needles. The judge said that "the harm the defendants sought to avoid was greater than the harm in violating the statute."
But opponents of the programs argue, as Mayor Dinkins did in New York when he eliminated the first government-sponsored needle exchange in the nation, that to distribute needles is "to surrender" to drug abuse.
The Bush Administration has barred Federal funds to pay for needles.
Needle-exchange programs are presently in operation in Honolulu; Portland, Ore.; Seattle and Tacoma, Wash., and Boulder, Colo.
In New Haven four workers from the city's Health Department distribute needles, bleach to sterilize the needles and condoms. The program, which uses a van that goes to areas with high drug traffic four times a week, has so far enrolled more than 700 drug users and exchanged more than 12,000 needles.
The workers have also helped enroll 107 addicts in drug treatment. But 60 other addicts who want to enter treatment have not been able to because of limited openings in the programs and the van's own staff limitations, Health Department officials said. They said state financing of the program for the current fiscal year was uncertain.
Mayor Daniels, a critic of needle-exchange programs as recently as two years ago, yesterday urged other mayors to support them. He said he had changed his mind after realizing how rapidly AIDS was spreading in his city and after talking to addicts and advocates of people with AIDS.
A spokeswoman for Mayor Dinkins said he would likely "take a close look at the findings." New York City has the highest AIDS caseload in the country, with more than 33,000 cases.