Federal officials detected a highly pathogenic avian influenza – otherwise known as bird flu – in a flock of birds in New York and Maine.
Samples from the non-commercial backyard flocks in Suffolk County, New York, and Knox County, Maine, were tested at Cornell University Animal Health Diagnostic Center and confirmed at the United States Department of Agriculture's (USDA) Animal and Plant Health Inspection Service laboratories in Ames, Iowa.
Bird flu can cause high mortality rates among birds. In 2015, 50 million birds across 15 states died due to an outbreak, costing the federal government nearly $1 billion.
However, officials in both states have "quarantined the affected premises" and the birds "will be depopulated to prevent the spread of the disease," according to notices posted by the USDA.
The USDA also noted that both flocks "will not enter the food system" and that the disease doesn’t present an immediate public health concern.
The virus has already been detected at four commercial turkey farms in southern Indiana in addition to one flock of commercial broiler chickens in Kentucky and a backyard flock of mixed species birds in northern Virginia.
The birds that were infected in Kentucky were being raised on a Tyson Foods farm in Fulton County. However, the company is only aware of one affected house at the farm, which is one of the thousands of farms that raise chickens for the company.
To mitigate the spread, Tyson is "heightening biosecurity measures at other farms in the region and placing additional restrictions on outside visitors and continuing our practice of testing all flocks for avian influenza before birds leave the farms."
Health officials say no human cases of avian influenza viruses have been detected in the U.S. The virus can spread from infected birds to people, but such infections are rare and haven’t led to sustained outbreaks among humans.
The USDA also noted that properly prepared and cooked poultry and eggs to an internal temperature of 165 degrees kill bacteria and viruses.
The Associated Press contributed to this report.