In other H5N1 developments, the FDA's vaccine advisory group said it will discuss the composition of H5 vaccines when it meets next month.
Massachusetts is the only state to test all dairies, which involved bulk-milk tank sampling in August.
Like most other H9N2 cases, China's latest illness involves a young child.
Also, sequencing confirmed N1 and identified two HA mutations, one of which could affect vaccine development.
Afghanistan's polio vaccine campaign raises concerns, given that WPV1 is endemic there and cases are rising.
Before March 2024, H5N1 had not been detected in 1,337 wastewater samples analyzed by the team.
The contract option will cover steps such as scale-up process validation and commercial readiness.
While sequencing shows similarity to the virus in cattle, the epi investigation might not be able to pinpoint a source.
The three farms were targeted for testing due to their connections with the first avian flu outbreak locations.
CDC lab experts are working on sequencing to identify the neuraminidase and detail the genome, which could yield clues about the source.
