LANCASTER COUNTY, Pa. — Another avian influenza outbreak has been discovered at a commercial poultry farm in Lancaster County, the U.S. Department of Agriculture said Wednesday.
It's the eighth poultry operation in the county to suffer an outbreak, the USDA said.
The USDA did not disclose the location of the most recent farm to be affected by the outbreak, which is a typically fatal strain. But 72,300 birds either died of the virus or were depopulated in an effort to prevent its spread.
Outbreaks were also confirmed by the USDA at two other farms in Berks County on Wednesday.
Berks and Lancaster counties are the only two areas in Pennsylvania where avian flu has been detected among domesticated poultry birds.
Avian flu was first detected in Lancaster County on April 15, according to the USDA. Since then, a total of 3,917,500 birds -- a combination of chicken and ducks including meat birds, egg layers, and pullets -- have been depopulated, the USDA said.
Depopulation is the term used for the euthanization of flocks to prevent the spread of the virus.
Avian influenza is most commonly spread when healthy birds come into contact with bodily fluids from infected wild or domestic birds, but it can also be spread by contaminated clothing or equipment, experts say.
Nationwide, avian flu has been confirmed in 301 commercial or backyard poultry operations in 34 states as of Wednesday, according to USDA statistics.
About 37.7 million birds have been affected by the outbreak, the USDA said.
The virus poses a low threat to humans, according to the U.S. Centers for Disease Control and Prevention, though in rare cases humans have contracted it.