NEW YORK (Reuters Health) - US researchers believe they are on the road to developing a safe and effective vaccine for the more than 1.5 million Americans with life-threatening peanut allergy.

As reported in the Journal of Allergy and Clinical Immunology, researchers created a vaccine against three allergy-causing proteins in peanuts. The vaccine proved "very effective" in mice with a peanut allergy, Dr. Hugh A. Sampson, from Mount Sinai in New York, said during a telebriefing Thursday.

"The highest dose gave markedly extended protection," according to Dr. Sampson. "Mice that were challenged [with peanuts] three months out after [receiving the vaccine] still retained full protection."

"This vaccine, which could be adopted for human use, provides some hope that within the next several years, we may be able to treat patients with [serious peanut allergies] and actually turn off the reaction," he said, predicting the start of human trials "within one year."

Elsewhere in the journal, Dr. Sampson and others describe a new method for diagnosing peanut allergy. "This test could dramatically reduce the need for oral challenge." Dr. Sampson told reporters.

The test, which relies on antibody differences between patients, could be commercially available within a few years, according to the report.