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Bird flu outbreak at dairy farms continue to raise concerns
5m 52s
The H5N1 virus, also known as bird flu, is spreading among dairy cows. It's been found in over 85 herds across 12 states and at least three farm workers have been sickened. While public health officials say the risk to humans remains low, concerns are growing. William Brangham discussed the threat with Rick Bright, former head of the Biomedical Advanced Research and Development Authority.