A new generation of HIV tests requiring just a swish of a plastic stick around the gums or a finger prick is being offered throughout the city, providing patients with fast results and giving health officials better hope that they can stop the spread of AIDS.

The tests for the presence of HIV antibodies produce results in 20 minutes. They are being administered in every borough.

In the Bronx, where nearly a quarter of the city's HIV infections and a third of AIDS deaths occur each year, tens of thousands of people are getting screened.

For decades, health workers have checked for HIV by drawing vials of blood and testing the samples in labs, requiring patients to wait for up to two weeks for results. The technique is still used, especially to double check positive results in rapid tests. The blood test, though, has drawbacks, health workers say, because patients sometimes can't be contacted or fail to return to the clinic to learn their results, increasing the chance they may infect others.

The new tests, which allow samples to be collected by scraping the gum line or pricking a finger for blood, ensure that almost every patient learns results the same day. They allow doctors and clinicians to refer the patient to counseling and treatment immediately if need be, said Judith Berger, chief of the infectious-diseases division at St. Barnabas Hospital in the Bronx.

In the past, "we've actually had patients die before they could get their results," said Ralph Belloise, director of HIV services at St. Barnabas. "The more people who know their status, the more people we get into care.... We decrease the community viral load and decrease the number of infections."

St. Barnabas Hospital began to offer rapid oral HIV testing in 2008 in inpatient and outpatient units and through the emergency department. Since May, tests also have been performed in the dental clinic, a natural place to scrape the mouth, workers say.
The multiple sites, and a grant that allows the hospital to offer the test for no charge, has led to a jump in the testing numbers. In 18 months between 2008 and 2009, the hospital performed 25,000 of the rapid and traditional HIV tests, while it's on track to do 18,000 this year.

"Some people come back constantly," said Toni Durand, the coordinator of the HIV testing grant at St. Barnabas Hospital. As a result, tests are being done on all kinds of patients, not just those in high-risk groups such as intravenous drug users and men who have sex with men. "Now we get grandmas and grandpas," she said.

Nearly 106,000 people were living with HIV/AIDS in New York City in 2008, a number that has grown steadily for the last 10 years, according to the city's health department. One in five people living with HIV do not know they are infected with AIDS.

Health advocates in the Bronx said they were especially eager to begin rapid HIV testing because of the borough's high incidence of HIV and AIDS. In 2008, the health department started The Bronx Knows, a borough-wide effort to increase voluntary HIV testing to ensure that all residents know their HIV status. About 75 community organizations, including hospitals, have administered more than 375,000 HIV tests as of June, yielding 1,275 positive diagnoses, according to the health department.

Other city hospitals and agencies are testing more people than ever and getting rapid results. The Health and Hospitals Corp., which runs the city-owned hospitals, tests at every hospital and many clinics. HHC performed 50,000 tests in 2004. Last year it tested nearly 190,000 people, said Terry Hamilton, director of HIV services. Nearly 90% of the tests offered this year will be rapid tests.

OraSure Technologies, Inc., based in Bethlehem, Pa., has sold the rapid oral test since 2002, and is working with the U.S. Food and Drug Administration to get approval for an over-the-counter oral-test kit for home use, said Doug Michels, the president and CEO. The kit is still years off, he said.

For now, vans run by nonprofits are trolling Bronx streets, carrying clinicians offering free tests. That's where Matthew Acevedo, 19 years old, got his first test, 18 months ago. He decided to check because he has four friends who are HIV positive.

He was relieved to discover he was negative. "You never know," said Mr. Acevedo, who hopes to start college next year. "You should just check yourself. I just want to know if I have it."