Six new cases of highly pathogenic avian influenza (HPAI) have been reported in Mexico and one new case has been reported in Argentina, according to the World Organisation for Animal Health (WOAH).

All seven cases involved commercial poultry operations.

Avian influenza in Mexico

Six broiler breeder flocks in Samahil, Mexico, were affected by HPAI, a recent report from the WOAH pointed out.

The total number of birds affected in these flocks amounts to 157,098. The smallest of the six flocks included 16,331 birds, while the largest included 36,032.

These six cases follow four other cases in Samahil, but all four of those cases involved commercial layer operations. In those cases, 1,736,040 hens were lost.

Samahil is a city in the Mexican state of Yucatán.

To date, Mexico has lost 18 commercial poultry flocks collectively involving 5,632,389 birds, to HPAI, according to WOAH data. Most of those birds – a little more than 5.2 million -- have been laying hens. The country has lost 18 layer flocks, seven broiler breeder flocks, one broiler flock and one layer breeder flock.


Avian influenza in Argentina

The second case of HPAI in Argentina was also reported by the WOAH. The most recent case involved “heavy breeder farm” in General Alvear.

There were two houses on the premises, involving a total of 17,000 birds. Of those, 6,082 had already died.

“On March 1, 2023, a notification was received at the local office due to mortality and official attention was given to the suspicion on the same day, with quarantine of the premises and sampling for diagnosis. On March 2, samples were received at the laboratory and on March 3, a positive result for AI type A subtype H5 was obtained at the official SENASA laboratory. On March 4, the official outbreak control measures began. All birds were culled and disposed of,” the WOAH report stated.

The report of this case came just days after Argentina’s first case of HPAI in commercial poultry was reported by WOAH. 

In that case, approximately 190,000 broilers were lost.

To learn more about HPAI cases in North American commercial poultry flocks, see an interactive map on

Read our ongoing coverage of the global avian influenza outbreak.