NEW DELHI, July 14 (Reuters) - India has approved human volunteer trials for the country's second preventive vaccine against HIV, the virus that leads to AIDS, health officials said on Thursday.

Home to the second-largest number of people living with the killer virus after South Africa, India started human trials on its first preventive vaccine in February and authorities say those are progressing well.

"All clearances have come for the human trials of a second vaccine," S.Y. Quraishi, director of the state-run National AIDS Control Organisation (NACO), told Reuters.

The trials on at least 30 volunteers will start in September. Scientists need to test different vaccines on the same or separate strains of a virus to develop the most effective antibodies.

A vaccine for the developing world, where anti-retroviral drugs are out of reach for millions of HIV-infected people, would be the ultimate prize in the fight against AIDS. But efforts to find one have been hampered by the virus's ability to mutate.

In February, researchers began trials on 34 healthy adult volunteers for tgAAC09 vaccine that targets HIV subtype C, widely prevalent in India, South Africa and China.

The trials for the second vaccine -- called the Modified Vaccinia Ankara (MVA) -- will be carried out at the Tuberculosis Research Centre in the southern city of Madras. The MVA will also target HIV subtype C.

PHASED TRIALS

Officials say in the first phase of such trials, vaccines are tested on healthy volunteers who are given a controlled dosage of the HIV subtype C virus to create resistance. All volunteers sign on to the trial, accepting the risks of possible HIV infection.

In the second phase, the vaccine is given to a small group of high-risk individuals -- sex workers, drug users and homosexuals -- to check for the efficacy of the dosage. They are not asked to alter their regular lifestyles.

If the vaccine is seen to work on both groups, it is given to a larger group of up to 1,000 people. All volunteers at every stage of the trial have to be HIV-negative when they sign up.

In the fourth and last phase -- if the results of earlier phases are found to be satisfactory -- marketing of the vaccine is done and post-marketing surveillance carried out. Experts say it takes years for a successful vaccine to be developed.

The International AIDS Vaccine Initiative (IAVI), which coordinates the global search for a vaccine, says India is important because of its advanced biomedical research facilities and strong pharmaceutical industry which has developed cheap and effective AIDS drugs that are exported across the globe.

India has an HIV/AIDS caseload of more than 5.13 million people and experts say that number could quadruple by 2010 as many people are still reluctant to discuss safe sex openly.

Many Indians cannot afford anti-retroviral drugs, which cost 1,300 rupees ($29.90) a month.

Human trials of vaccines against different HIV strains of the are being conducted in the United States, Europe and Africa. ($1=43.55 rupees)

US needle exchange programs declining

Thu Jul 14, 2005 07:21 PM ET

NEW YORK (Reuters Health) - Some needle exchange programs in the US have ceased operations in recent years, and public funding for these programs has declined, according to a report released today.

Needle exchange programs help prevent transmission of HIV and other bloodborne infections by increasing access to sterile syringes among injection drug users (IDUs) and safely disposing of used syringes. Exchange programs also offer social services, such as provision of condoms, referrals for substance-abuse treatment, and testing for HIV and hepatitis.

In 2003, Dr. C. A. McKnight, from New York's Beth Israel Medical Center, and colleagues conducted surveys among 148 exchange programs known to the North American Syringe Exchange Network.

"In 2002, for the first time in 8 years, the number of exchange programs, the number of localities with exchange programs, and the amount of public funding for exchange programs in the United States decreased," the authors note in the Morbidity and Mortality Weekly Report, a publication of the Atlanta-based US Centers for Disease Control and Prevention.

Specifically, the number of needle exchange programs declined from 154 to 148 from 2000 to 2002, primarily through loss of small programs, while the number of states and territories with exchange programs fell from 35 to 32. Public funding decreased 18 percent.

At the same time, the number of syringes exchanged increased 20.2 percent and total budgets increased 7.4 percent.

Such programs "provide health and social services to IDUs who might not otherwise be reached," the authors conclude. "Continued monitoring of exchange programs in the United States is necessary to evaluate the long-term effects of this public health intervention."

SOURCE: Morbidity and Mortality Weekly Report, July 15, 2005.

Rise in needle exchanges, study shows

Thu Jul 14, 2005 5:39 PM ET

By Paul Simao

ATLANTA (Reuters) - The number of syringes traded at needle exchange sites grew in the United States despite efforts by political conservatives to stop the programs, which they say promote drug use under the cover of HIV prevention.

About 24.9 million syringes were exchanged at clinics, mobile vans and other sites in 2002, compared to 22.6 million in 2000, according to a survey published on Thursday by the Centers for Disease Control and Prevention.

The increase occurred despite a decline in the number of known needle exchange sites as well as a drop in public funds for the controversial programs, said researchers at New York's Beth Israel Medical Center, which conducted the survey.

Many states and cities have cut needle exchange funding in a bid to cope with budget shortfalls.

Don Des Jarlais, one of the survey's researchers, said the findings highlighted the continuing importance of needle exchange programs, which mushroomed following the peak of the AIDS epidemic in the early 1990s.

HIV, the virus that causes AIDS, can be transmitted by sharing used syringes. AIDS activists see needle exchanges as a key weapon in the battle to halt the spread of HIV and other infections, especially among those who inject street drugs.

But needle exchanges are anathema for many politicians, especially in conservative states. New York, California and a handful of other states accounted for more than two-thirds of needle exchange programs covered in the 2002 survey.

"In New York City, we've seen a 75 to 80 percent decline in the rate of new infections with the expansion of syringe exchanges," said Des Jarlais, who added that the programs often provided other important health services, such as HIV testing and drug treatment referrals.

Needle exchange may also lead to a reduction in risky behavior in a group considered highly vulnerable to HIV.

Study: 6.5M South Africans May Have HIV