H7N9 Bird-Flu Outbreak is Harder to Track

The Wall Street Journal
December 03, 2013 AT 12:25 AM
Hong Kong is on public-health alert after the city confirmed its first human case of the deadly H7N9 bird flu. The WSJ's Deborah Kan speaks with Professor Ben Cowling from the University of Hong Kong about how this bird-flu virus is harder to track.