Affected states include Arizona, Illinois, Indiana, Kentucky, Minnesota, Montana, New Hampshire, Oregon, Texas, Utah, West Virginia, Washington, Wisconsin, and Wyoming.
APHIS also notes several outbreaks in backyard flocks.
The vaccine will be developed on a baculovirus platform.
All 21 cases in 2025 have been reported from mainland China.
A seventh young child in Israel, a 1-year-old, has died this year from measles.
Over the last 30 days, highly pathogenic avian influenza (HPAI) has been confirmed in 38 flocks.
Infectious virus persisted throughout the cheese-making process and aging in cheeses made with raw milk at pH levels above 5.0.
Mexico has seen 55 human cases of New World screwworm this year.
Iowa, Minnesota, and Wisconsin report new detections, part of rising activity over the past several weeks.
The outbreaks are part of an early uptick in H5N1 activity in poultry that began in late August, mainly in the Midwest.
