Test Finds Easily Transmitted Bird Flu Hard to Create CDC researchers swapping genes in the H5N1 bird flu virus say it won't be simple for that strain to mutate into a pandemic form.
NPR logo Test Finds Easily Transmitted Bird Flu Hard to Create

Test Finds Easily Transmitted Bird Flu Hard to Create

Researchers at the Centers for Disease Control and Prevention are trying to find out what it will take for the Asian bird flu virus to touch off a pandemic. They report that it won't be simple.

In a high-security lab in Atlanta, scientists have been swapping genes between human flu viruses and H5N1, the Asian bird virus that's killed 131 people so far. They want to see what would make the virus easily transmissable from one person to another.

So far, it's not easy to do. The gene combinations they've tried don't create a laboratory virus with pandemic potential.

That's good news. But CDC Director Julie Gerberding says she's not reassured.

Though we weren't able to do this through simple gene exchanges, there are many other combinations and subtle changes the virus itself could make," Gerberding said. "So let's not use the word reassuring."

The report appears in the Proceedings of the National Academy of Sciences. -- Richard Knox

No 'Black Box' Safety Warning for ADHD Drugs

July 31, 2006 -- Manufacturers of attention deficit-hyperactivity disorder drugs will not have to add new "black box" safety warnings.

ADHD drugs already carry special warnings about addictiveness and misuse that can lead to heart problems. The FDA asked two advisory committees last winter if more were needed. One committee called for a new black box warning about increases in blood pressure and heart rate. The second said an information packet would be enough.

Last week, without fanfare, the FDA approved a new label for Shire Pharmaceutical's ADHD drug Adderall -- with no black box. However, new warnings in the middle of the label carry more specifics on cardiovascular problems. They also now advise doctors to be cautious in prescribing Adderall to people with manic-depressive disorder , and to watch patients for psychotic symptoms or increased aggression. -- Joanne Silberner