PubMed study finds no evidence of efficient airborne transmission of clade 2.3.4.4b H5N1 between ferrets in controlled laboratory setting.
Public note
For situational awareness and research transparency. Not medical advice.
Monitoring clade 2.3.4.4b evolution, mammalian adaptation markers, and zoonotic spillover events across dairy cattle, poultry, and wild bird populations.
Open assessments
Tracked assessments currently open in this scope.
Evidence items
Source-attributed evidence available to this scope.
Source feeds
Configured sources contributing data to this investigation.
Last activity
Most recent scope activity captured in the system.
Evidence quality mix
01
The current analyst view of this scope, at increasing levels of depth.
Active monitoring. 5 open assessments, with rising confidence in mammalian adaptation.
Clade 2.3.4.4b H5N1 continues to circulate widely in wild birds and poultry across multiple continents. Since late 2024, dairy cattle outbreaks in the US have raised concerns about mammalian adaptation. GISAID sequences show PB2 E627K and D701N mutations in several bovine isolates. WHO has not declared a PHEIC but maintains elevated risk assessment. The system is following 5 open assessments covering sustained cattle-to-cattle transmission, human spillover probability, and antigenic drift away from candidate vaccines.
02
Open assessments being tracked inside this scope, ordered for fast review.
03
The most recent source-attributed evidence flowing into this investigation.
PubMed study finds no evidence of efficient airborne transmission of clade 2.3.4.4b H5N1 between ferrets in controlled laboratory setting.
GISAID sequences show PB2 E627K mutation in 4 new bovine H5N1 isolates from Texas and Ohio dairy herds, collected March 2026.
WOAH-WAHIS notification: 12 new HPAI H5N1 outbreaks in US dairy cattle, spanning Texas, Ohio, and Michigan. Case fatality rate in affected herds estimated at 2%.
ProMED post reports farmworker in Texas hospitalized with conjunctivitis and mild respiratory symptoms following exposure to infected dairy cattle. PCR-positive for H5N1.