Large-scale mortality among snow geese has led the Pennsylvania Game Commission to declare Lehigh Valley the epicenter of a resurgent bird flu outbreak that is so far severely affecting waterfowl but sparing the state's commercial and backyard poultry flocks.
Rising egg prices are the most visible sign that the latest surge of a Highly Pathogenic Avian Influenza (HPAI) outbreak that started in the United States in 2022 is impacting consumers, but health experts say the food supply is secure -- excluding raw milk.
The Game Commission has not updated its guidance to hunters in the region as deaths continue to rise among waterfowl, with particularly grim results for migratory snow geese.
Hunters who take proper precautions -- wearing gloves and sanitizing equipment -- can operate under the knowledge that healthy appearing birds present a lower risk of spreading the virus, said Travis Lau, a Game Commission spokesperson.
After consulting with a Game Commission veterinarian, Lau offered the following guidance to hikers and others who might encounter sick or dead birds, in particular the migrating waterfowl and shorebirds who have proven most susceptible to the virus:
HPAI is a virus that survives in cold temperatures, making the winter migratory season a particularly risky time in which snow geese and other migrating waterfowl can not only spread the virus within their populations, but also generate feces that allow the virus to spread in bodies of water and on the banks of rivers and lakes.
The virus survives in moist places where organic matter is present, making leaf packs and other shoreline environments areas of high risk.
Because the virus is largely transmitted through feces, the site at which sick and dead birds are found probably poses a greater risk of exposure and virus spread than dead bird carcasses do (although the virus does remain alive inside those carcasses), Lau said.
"Until the virus dies off, that risk remains," Lau said, adding that it is not possible to decontaminate a wild site.
A Jan. 2 Game Commission news release called attention to 200 total snow geese found dead at two sites: one in Lower Nazareth Township in Northampton County and another in Upper Macungie Township in Lehigh County.
In the intervening weeks, the Game Commission has asked the public to report sick or dead bird sightings. Lau said calling the commission at 1-833-PGC-WILD (1-833-742-9453) is the most effective tool, as many reports filed through email ([email protected]) or the online Wildlife Health Survey tool were found to be duplicate reports.
Lau noted that there has been a lot of attention paid to mortality numbers at the two greater Allentown area sites, in part because commission depopulation efforts to combat the spread of the virus, alongside the virus' natural spread, have led to a dramatic spike in bird deaths.
As of Jan. 17, 5,000 snow geese (including the 150 initially reported dead in the Jan. 2 news release and 450 shot in depopulation efforts) had died at the Lower Nazareth Township site, with an additional 150 dead at the Upper Macungie Township site (including the 50 dead listed in the Jan. 2 report).
"This is a problem that hasn't gone away," Lau said, emphasizing that reports indicate the problem is much wider than those two sites.
A cumulative spread of cases across Pennsylvania, following a resurgence of the virus in other states, does appear to center on the Lehigh Valley, Lau said. But he added that it's hard to quantify the impact of greater awareness and reporting from the densely populated Lehigh Valley in comparison to other areas of the state where that data might not be adequately captured.
The HPAI outbreak that began in the United States in 2022 led to large-scale cullings of commercial poultry flocks. Wild birds, especially migrating waterfowl, are primary carriers of the disease.
Farms have had to step up biosecurity measures -- such as placing flocks under roofs to protect them from dropping feces -- to avoid risking another large-scale outbreak.
In the past 30 days, 98 flocks nationwide have been found to have confirmed infections: 57 commercial flocks and 41 backyard flocks, according to the U.S. Department of Agriculture. Nearly 15.5 million birds have been affected by the highly contagious and fatal virus.
HPAI spreads fast in commercial poultry flocks and has been shown to have mortality rates between 90-100%. Affected flocks are culled. Since the 2022 start of the outbreak, USDA data shows more than 4.7 million affected birds in Pennsylvania, spread between 32 commercial flocks and 39 backyard flocks, with the most recent detection in the state coming in October 2024.
The USDA also tracks outbreaks in other species, as the virus has been found in dairy cows and other mammals. Affected species include domestic and wild cats, bears, foxes, raccoons, rodents, skunks and opossums.
Both Lau and Pennsylvania Department of Agriculture spokesperson Shannon Powers noted that there can be a lag time in confirmations of HPAI cases in wild birds. The USDA sites for poultry and cattle detections are updated each weekday.
HPAI has several strains -- the dominant H5N1 virus strain has proven capable of spreading to humans. The first U.S. case of a human contracting that strain occurred in April 2022. The federal Centers for Disease Control and Prevention reported that the patient -- a worker who was depopulating an infected poultry farm -- recovered after a few days of fatigue.
Since then, more human cases have been reported, with most affecting workers who have participated in cullings of commercial poultry flocks or who have handled sick cattle.
On Jan. 6, the Louisiana Department of Health reported the first fatal human case of H5N1 in the United States, with a news release stating "the patient was over the age of 65 and was reported to have underlying medical conditions. The patient contracted H5N1 after exposure to a combination of a non-commercial backyard flock and wild birds."
Those visiting or working on farms should take biosecurity precautions (such as wearing boot covers and other protective clothing, including googles worn while milking) to avoid spread among poultry flocks or livestock herds and the potential of further spread among humans. Yet health experts believe the general risk to the public to still be at a low level.
Eating properly cooked eggs, meat or pasteurized milk will not bring a food safety risk, said Kathleen Bachynski, assistant professor of public health at Muhlenberg University College.
Bachynski directed consumers to CDC guidance on proper cooking temperatures, noting that eggs and poultry should be cooked to 165 degrees.
The main thing consumers should avoid is drinking raw milk or giving raw milk to pets, Bachynski said.
Bird flu has been found in cats. What to know and how to protect them.
"The reason for that is that raw milk has not been pasteurized, so it does still have the potential to have not only avian virus but also E. coli, salmonella -- all kinds of microorganisms that can be dangerous to people," Bachynski said.
Lehigh Valley residents may have seen signage in local grocery stories indicating that avian flu has affected the egg supply.
"Avian flu has significantly impacted the supply and price of commodity eggs," Dennis Curtin, director of public relations for Weis Markets, said in an email. "But it has not impacted the supply and pricing of specialty eggs."
Curtin notes that since Oct. 15 nearly 30 million laying hens have been lost to avian flu, which impacted pricing during a period when eggs were at their highest demand due to holiday baking.
"The resulting shortage has impacted the price of Grade A commodity eggs and narrowed the pricing difference between commodity eggs and specialty egg prices," Curtin said.
That narrowing of the price difference has increased demand for specialty eggs, causing some items to occasionally go out of stock, Curtin said. He added that Weis is bringing in new specialty egg items to meet the increased demand and that Weis brand specialty and commodity eggs have remained available in good supply.