An outbreak of virulent Newcastle disease (VND) virus among backyard chickens in California exemplifies the need for biosecurity diligence year-round, according to Texas A&M AgriLife Extension Service poultry specialist Dr. Craig Coufal.
Coufal said chickens infected with the disease so far have been isolated to two counties in southern California. This is the same area where the last VND outbreak (then known as exotic Newcastle disease) occurred in 2003, which eventually led to infections in commercial flocks. No infections have been reported among commercial flocks in the U.S. with the current outbreak, according to the U.S. Department of Agriculture.
“They’ve identified the disease in backyard flocks there in California, and the outbreak has been contained to those areas where the chickens were located,” he said. “This is just a good time to consider flock biosecurity, because this is proof we need to be diligent year-round.”
VND is a highly contagious and fatal virus affecting the respiratory, nervous and digestive systems of birds and poultry, according to USDA. The disease is so virulent that many birds and poultry die without showing any clinical signs.
Coufal said when birds do show signs of viral infections, including of other diseases such as avian influenza or infectious laryngotracheitis, they typically act abnormally. They stop eating, are lethargic, cough or sneeze and, in the case of laying hens, cease producing eggs.
No human cases of VND have ever occurred from eating poultry products, Coufal said. Properly cooked poultry products are safe to eat. In very rare instances, people working directly with sick birds can become infected with mild symptoms.
Coufal said some tips for biosecurity include:
* Secure poultry houses against wild birds, pets and livestock.
* Restrict visitors from houses and coops, especially without thorough disinfecting.
* Dedicate specific shoes or rubber boots for exclusive use in poultry houses.
* Wash and disinfect any shared equipment such as scales, feeders and drinkers.
* Initiate rodent and insect control programs.
* Acquire birds from sources that have tested for diseases.
“While this outbreak is concentrated to a specific area and officials are sure of its source, this highlights the need to practice proactive disease control,” Coufal said. “If you don’t report a disease outbreak and seek help to control its spread, then isolated cases can get out of hand and turn into massive outbreaks.”