LANCASTER, Pa. (WHTM) – Over 16,000 birds in Lancaster County are being affected by a new Avian flu outbreak, according to the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service.

The new cases were reported on March 13 and 14 on the department’s national list of confirmed detections.

Thousands of birds were also reported to be affected in Lancaster and Bucks counties on March 6.

Currently, Pennsylvania has four affected commercial flocks and 19 affected backyard flocks, according to the USDA.

According to Lancaster Farming, the state’s Agriculture Department reported most of the affected birds in the last week were duck flocks in Brecknock Township.

Nationally more than 58 million birds in 321 commercial and 475 backyard flocks have been affected by Avian flu.

Pennsylvania has been the nation’s hotbed for outbreaks this year with more than 215,000 birds affected by the outbreak.