A handful of children once severely allergic to peanuts now can eat them without worry. Scientists have retrained their immune systems so they're allergy-free.

It's a small study and doctors stress not to try this at home — it could spark a deadly reaction. But scientists at Duke University and Arkansas Children's Hospital gave children very tiny amounts of peanut flour daily for over two years.

Gradually the kids became less sensitive. So far, five show no remaining sign of the allergy.

Larger studies are beginning to see if the treatment works for more people and how long it lasts. But it marks new hope for the nearly 2 million Americans who are allergic to peanuts.

The findings were announced Sunday at a meeting of allergy specialists in Washington.