Scientists at Elan Corporation say an experimental vaccine to fight Alzheimer's disease passed its first test and appears to be safe for humans.

Read about attempts made by health authorities to prevent the spread of the West Nile virus. Includes a video clip of a CNN report.

Findings of a doctors' group say that antibiotics are not needed for treatment of most upper respiratory infections. Find out why.

Read about a new antibiotic, Zyvox, which is the first in a new class of antibiotics in 35 years. Find a video clip of a CNN report.

Members of the Global Polio Partners Summit say they have 30 countries to go before the eradication of polio.

Studies demonstrated that the flu was surprisingly common among babies and costly. Find out if this discovery will lead to infant vaccinations.