This is the VOA Special English Health Report.
researchers say they still have much work to do on a vaccine against H.I.V. But
the first reports of some success have raised hopes. Scientists say an experimental
vaccine reduced the risk of infection in humans by thirty-one percent and was
study was designed to test for two abilities. One was the ability of the
vaccine to prevent H.I.V. infections. The other was its ability to reduce the
amount of virus in the blood of people who became infected during the study.
Volunteers received vaccinations over a
period of six months and were tested for H.I.V. for an additional three years. The
study began in two thousand three. It was the largest AIDS vaccine trial yet.
It involved more than sixteen thousand adults in Thailand.
received the vaccine. The other half received a placebo, an inactive substance.
The volunteers did not know which they were getting.
people in the placebo group became infected during the study. The researchers
say that was compared with only fifty-one of those who received the vaccine.
Supachai Rerks-Ngarm, who led the study for the Thai Ministry of Public Health,
called it a scientific breakthrough.
Surgeon General of the United States Army sponsored the study and released the
final results last week.
The National Institutes of Health also
took part. Doctor Anthony Fauci at N.I.H. called the findings an important step
forward. He said it represents the first time an investigational H.I.V. vaccine
has shown some ability to prevent infection. But he also said additional
research is needed to better understand how the vaccine reduced the risk in those
vaccine did not lower the amount of virus in the blood of volunteers who became
infected during the study.
The study was based on versions of H.I.V.
commonly found in Thailand. The volunteers received a combination of two
vaccines. The first, or prime, vaccine came from the Sanofi Pasteur company. The
second, or booster, vaccine was developed by VaxGen. The nonprofit group Global
Solutions for Infectious Diseases now has rights to it.
Neither vaccine had been successful by
itself when tested earlier. More detailed results of the study are expected to
be presented at an AIDS vaccine conference in Paris next month.
that's the VOA Special English Health Report, written by Caty Weaver. For more
health news, go to voaspecialenglish.com. I'm Steve Ember.