Photo illustration
Homeowners with backyard chickens have now given federal agriculture officials reason to worry. A contagious viral disease affecting the respiratory, nervous and digestive systems of birds and poultry is spreading through backyard exhibition chickens in Los Angeles and San Bernardino counties in California.
Virulent Newcastle Disease or vND is not a foodborne illness, but humans working with or around sick birds can be infected and develop mild symptoms. For infected poultry, however, vND means certain death.
Commercial poultry in the United States has been vND-free since 2003, according to federal officials. If the disease migrates to commercial flocks from the backyard flocks in California, international markets could be shutdown overnight.
“Samples from the (backyard) flocks, which experienced increased mortality, were tested at the California Animal Health & Food Safety Laboratory System (CAHFS). The APHIS National Veterinary Services Laboratories in Ames, Iowa, confirms all findings,” APHIS reported when it announced nVD had been found in San Bernardino County.
“APHIS is working closely with the California Department of Food and Agriculture to respond to these findings, and is investigating any potential links between these cases and the case recently identified in Los Angeles County. Federal and state partners are also conducting additional surveillance and testing in the area.”
If vND shows up in commercial poultry flocks, APHIS is ready with a 164-page emergency response plan called “The Red Book.”
For now, however, the agency wants to remind all owners of backyard poultry to strictly follow “solid biosecurity practices” to protect their birds from infectious diseases. According to APHIS, owners of backyard chickens should follow three basic steps, including:
- Washing hands and scrubbing boots before and after entering an area with birds.
- Cleaning and disinfecting tires and equipment before moving them off the property; and
- Isolating any birds returning from shows for 30 days before placing them with the rest of the flock.
Owners of backyard flocks should report any unusual bird deaths to their state veterinarians or by using USDA’s toll-free number at 866-536-7593. Birds and poultry will die without showing any clinical signs once vND strikes a flock.
Veterinarians say most local ordinances that have enabled the backyard chicken craze have little to say about public health. Instead, they’ve focused only on controlling nuisances, like prohibiting roosters. One result of that focus is backyard chickens somewhere are almost always involved in a Salmonella outbreak.
In a current outbreak, backyard poultry flocks infected with six strains of Salmonella are responsible for 124 illnesses across 36 states, according to the federal Centers for Disease Control and Prevention in Atlanta. A third of the victims are children younger than 5.
It is the 71st multi-state Salmonella outbreak linked to backyard poultry since 2000.
The CDC says those outbreaks sickened 4,794 people, including 894 who were hospitalized and seven who died. The largest number ever recorded of Salmonella illnesses from backyard flocks occurred in 2017 when the CDC recorded 1,120 cases in 48 states; 249 people were hospitalized and one died.
USDA’s “Red Book” says vND “is a zoonotic disease, though not one that poses a significant threat to public health. Infections in humans are usually characterized by conjunctivitis, though mild, self-limiting influenza-like symptoms have been reported.”
It says individuals most at risk for vND are those exposed to large quantities of the virus through direct contact with infected poultry, like laboratory workers and vaccination crews.
The Red Book also says no known human infections have occurred from eating poultry products. In very rare instances people working directly with sick birds can become infected, according to the document. Symptoms are usually very mild and limited to conjunctivitis. Infection is easily prevented by using standard personal protective equipment, the APHIS emergency response plan says. Officials are ready to protect public health if necessary.
“In the event of an vND outbreak, animal health officials will collaborate with public health officials. In addition to the potential public health threat, there may also be a significant social and psychological impact on flock owners,” according to the plan.
(To sign up for a free subscription to Food Safety News, click here.)