Highly Pathogenic Avian Influenza A (HPAI) H5N1 virus is an emerging disease in cattle. Federal and State
agencies are moving quickly to conduct additional testing for HPAI (H5N1) virus, including viral genome
sequencing to provide a better understanding of the situation to characterize the HPAI (H5N1) virus strain
or strains associated with these detections as well as other components of this disease event at the
connection between animals, people, and the environment. The genetic and epidemiological data indicate
spillover of the virus from wild birds to dairy cows and some instances of spread from dairy to dairy and
from dairy premises to poultry premises. Based on this analysis, we have learned that the whole genome
sequence for virus found in positive herds in 8 states and on two recent commercial poultry premises in
two different states indicates it is the same strain affecting both dairy cattle and poultry. While it is still
unclear exactly how virus is spreading, the virus is shed in milk at high concentrations; therefore, anything
that comes in contact with unpasteurized raw milk, spilled milk, etc. may spread the virus including other
animals, vehicles, and other objects or materials. Therefore, both dairy and poultry producers should re-
double biosecurity efforts and be vigilant about monitoring for and controlling disease in their herds and
flocks.
Additionally, in order to continue to monitor and understand the extent of this virus and reduce the risk of
further spread of HPAI H5N1, resulting in greater threats to poultry and livestock, APHIS issued a Federal
Order on April 24, 2024 that requires premovement testing for lactating dairy cattle moving interstate and
reporting of positive test results from all laboratories and State Animal Health Officials (SAHO). This
document outlines both the interstate movement requirements, as well as APHIS recommendations to
limit the spread. Updated laboratory guidance, including details on required reporting, are located on the
APHIS website.
Our goal is to safeguard the health of U.S. livestock and poultry, protect the industry, keep our food supply
safe, and protect public health and human safety based on the most up-to-date information we have. We
continue to work diligently to understand the risk factors associated with this virus, transmission routes,
and pathogenicity in cattle. This continues to be a rapidly evolving situation. USDA and Federal and State
partners will continue to share additional updates as soon as information becomes available.
Scope and Definitions
Per the Federal Order, these steps are immediately required for lactating dairy cattle. Any requirements for
other classes of dairy cattle, or expansion beyond dairy cattle, will be based on scientific factors concerning
the virus and its evolving risk profile.
Definitions used in this document:
•
Cattle – The requirements outlined within this guidance apply to the movement of members of the
Family: Bovidae; Subfamily: bovinae; Genus: Bos; Species: Bos taurus and Bos indicus.
•
Lactating – The requirements outlined within this guidance apply to the movement of dairy cows
currently in one of the lactation phases (i.e., early, mid, and late) of their current production cycle.
•
Dairy – The requirements outlined within this guidance apply to the movement of lactating cattle
breeds raised for the primary purpose of milk production.
•
Nonlactating – Nonlactating cattle include: heifers, dry cows, and bull calves.
•
Affected herd – Any dairy cattle herd with suspect, presumptive, or confirmed positive cattle cases
present as defined in the case definition,
or exposed cattle present.
•
Exposed cattle – Any cattle that have been on the same premises as an affected herd within the