Avian influenza has killed millions of birds and caused egg prices to soar since it first emerged in U.S. poultry in 2022.
The virus has since jumped to mammals and even people. The Centers for Disease Control and Prevention have confirmed 973 dairyherds infected with bird flu as of Feb. 21. And 70 cases among people in the U.S. since March of last year.
Cases of the avian flu, or H5N1, in dairy cows in Nevada and Arizona have scientists rethinking how the virus spreads.
One scientist, influenza virologist Seema Lakdawala, told the Guardian the virus is now endemic in cows, and is unable to be contained. What do we know about the strain detected in cows and how it might affect mitigation efforts?
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