In the rare cases when the H1N1 virus kills, scientists have found, it penetrates deep into the lungs, creating widespread damage -- a pattern similar to what killed millions during previous flu pandemics in 1918 and 1957.
Over the past week, I've been inundated with questions about swine flu, via Facebook, Twitter, CNN blogs and e-mail. So this week I'm empowering people with information about swine flu: how to protect yourself, what all the numbers mean and why you shouldn't freak out.
A year ago, headlines were screaming about a looming disaster: the rapid spread of bird flu across two-thirds of the globe. The H5N1 strain of the virus was killing more than half its human victims. Experts were urging the government to stockpile medicine and experimental vaccines.
Elderly people, whose immune responses typically weaken with age, can be safely protected against common influenza with doses of vaccine that are up to four times stronger than usual, researchers said Monday.
Health experts warn that things are falling into place for a global flu pandemic like the one in 1918 that killed tens of millions of people worldwide. They say it might not be quite as extreme, but by all calculations, will be very dangerous.