On Feb. 13, 2026, the Arizona Department of Agriculture announced that the United States Department of Agriculture officially advanced Arizona to Stage 4 Unaffected State Status under the National Milk Testing Strategy.
This development follows a year-long effort by the department to monitor and contain Highly Pathogenic Avian Influenza in the state’s dairy herds. The strategy was implemented to safeguard consumer health and safety while promoting Arizona’s agriculture sector, according to the official website.
The department agreed to support the USDA’s Highly Pathogenic Avian Influenza National Milk Testing Strategy in January 2025 through On-Farm Bulk Tank Milk sampling. This approach was chosen over silo sampling due to most Grade-A dairies supplying a single cooperative that markets to one large processor. The department said this structure made on-farm sampling more effective for rapid identification, quarantine, and investigation of non-negative detections.
Additional measures included three Director’s Administrative Orders that placed restrictions on Certificates of Veterinary Inspection validity periods, required testing of lactating dairy cattle at livestock auctions, and mandated nasal swab PCR testing for non-lactating dairy cattle destined for licensed Arizona dairies. The first two orders remain active; the third was rescinded on Aug. 20, 2025.
The first non-negative detection occurred at the end of January with a D1.1 genotype HPAI virus found in a dairy herd with no clinically ill cattle or reduced milk production. The last detection from on-farm bulk tank milk sampling was reported on July 24, 2025. Since then, six rounds of monthly sampling have yielded all non-detected results.
The department recognized its employees’ efforts in collecting nearly 1,000 samples and acknowledged diagnostic support from the Arizona Veterinary Diagnostic Lab and partnerships with public health agencies and dairy producers. Testing and monitoring will continue until USDA achieves Stage 5 eradication from the national dairy herd. The department operates within the agriculture sector and facilitates connections among people, food resources, and producers while offering services such as licensing, inspections, and oversight of agricultural practices according to its official website. Arizona agriculture benefits from a climate that supports year-round growth according to the official website.
For more information about these efforts and ongoing initiatives, visit the official notification.
