Chinese scientists have discovered the first case of human-to-human transmission of the H7N9 bird flu.
In research published in the British Medical Journal, scientists said that a 32-year-old woman contracted an infection while caring for her father. Both the woman and her father have since died.
(Read more: Could China's Bird Flu Be the Next SARS?)
While this is the first identified instance of a person catching the H7N9 virus through means that did not involve direct contact with birds, experts have noted that it does not mean the virus can now spread easily among humans.