About 10,000 chickens died as a result of exotic Newcastle disease and more than 10,000 others were depopulated during containment efforts following an outbreak in Mexico just south of California.
A report from the World Organisation for Animal Health (OIE) indicates the outbreak was discovered Jan. 26 in the Mexican state of Baja California near the California border. A second outbreak was discovered Jan. 31 in the state of Hidalgo in central Mexico. The infection sources were not immediately determined for the outbreaks, and few details on the second outbreak were available in the weeks following the report.
Exotic Newcastle disease is a frequently fatal viral disease that affects all species of birds and is one of the world's most infectious poultry diseases, U.S. Department of Agriculture information states. Some birds show no signs of infection prior to death, and others display signs such as sneezing, gasping, nasal discharge, diarrhea, depression, tremors, drooping wings, circling, paralysis, and swelling near the eyes and neck.
The Baja California outbreak involved 21,000 birds at a fattening farm, of which about 10,000 died of the disease, 10,050 were depopulated, and 50 were sent to slaughter, according to the OIE. Information on the remaining 900 birds was not available.
The Hidalgo outbreak involved at least 500 birds at a poultry breeding farm, and OIE information indicates planned control measures included depopulating sick and contaminated animals.
Joelle R. Hayden, a spokeswoman for the USDA Animal and Plant Health Inspection Service, said U.S. poultry have been free of END since 2003, and the department is working with other federal and state authorities to ensure the nation remains free of the disease.
"While there is no known direct threat to U.S. poultry, it is a good time to remind people who raise poultry to always practice good biosecurity and to be vigilant in reporting suspected foreign animal diseases," Hayden said.
Dr. Annette M. Whiteford, California state veterinarian, said her state is particularly sensitive to the risk posed by END because of an outbreak that affected commercial poultry flocks and backyard chickens in 2002 and 2003. The California Department of Food and Agriculture is working with the USDA, which has also encouraged federal customs and border control officials to increase attention to poultry moved across the border.
The spread of END to commercial and private flocks after its discovery in California backyard flocks in October 2002 led to quarantines in parts of California, Nevada, Arizona, and Texas.
California agriculture officials have contacts in feed stores, 4-H Clubs, livestock auctions, and flea markets where chickens are sold, and they have been distributing information on signs of END and where to report a suspected problem, Dr. Whiteford said. The state has also contacted commercial producers and reminded them to talk with employees about looking for signs of the disease.
The California Animal Health and Food Safety Laboratory System also sent clients notices to watch for signs of infection, and laboratory officials conduct free diagnostic work for backyard or hobby bird keepers who suspect Newcastle infections, Dr. Whiteford said. She also encouraged veterinarians in private practice to watch for the disease among patients brought in by owners of small flocks.