Mystery Bird Disease Update: State Lifts Feeder, Bath Moratorium

PENNSYLVANIA — The Pennsylvania Game Commission has lifted its recommendation to stop feeding birds as reports of sick and dead wild birds have decreased across the state.

The cause of the mortality event that swept Washington, D.C. and at least 10 states since May remains unknown, a news release said. But research has ruled out many potential causes and there is no indication that feeding birds or maintaining bird baths were contributing factors.

Originally, recommendations to take in birdfeeders and birdbaths stemmed from a desire to limit areas in which birds typically congregate.

The game commission also said that no human or domestic animal issues have been documented in connection with the mystery disease. The game commission said its grateful for the public's support in attempting to identify the mortality event's source.

“The public plays a vital role in wildlife health surveillance”, said Game Commission Wildlife Veterinarian Andrew Di Salvo. “They are often the first to notice and report injured, sick, or dead wildlife. All those extra sets of eyes and ears enables us to respond as quickly as possible and resolve or investigate the situation. We certainly appreciate their vigilance and look forward to continue to work closely with them into the future.”

At one point, the game commission had received reports of sick or dying birds from almost all counties in Pennsylvania.

Natural resource management agencies in the affected jurisdictions continue to work with diagnostic laboratories to investigate possible causes of this event. The USGS National Wildlife Health Center, the University of Georgia Southeastern Cooperative Wildlife Disease Study, the University of Pennsylvania Wildlife Futures Program, the Indiana Animal Disease Diagnostic Laboratory, and multiple state labs have been involved.

Based on results received to date, the following pathogens have not been detected in any of the birds tested: Salmonella and Chlamydia; avian influenza virus, West Nile virus, coronaviruses, Newcastle disease virus, herpesviruses, and poxviruses; and Trichomonas parasites.

Toxicology tests have been negative for heavy metals along with common pesticides and herbicides. Transmission electron microscopy and additional diagnostic tests, including metagenomics work, are ongoing.

Because birds congregate at birdfeeders and baths, the standard recommendation to keep that equipment clean remains in place, along with additional guidelines:

• Clean feeders and bird baths with soap and water, then disinfect with a 10 percent household bleach solution. After allowing 10 minutes of contact time, rinse with clean water and allow to air dry. Cleaning and disinfection should be done at a minimum weekly basis or more frequently when soiled to prevent potential spread of any infectious diseases between birds and other wildlife, as well as remove spoiled food.
• When feeding birds, follow expert recommendations such as those listed in Audubon International’s Guide to Bird Feeding.
• Remain vigilant and report any sick or dead wild birds to your local Pennsylvania Game Commission office.
• Keep pets away from sick or dead wild birds.
• Avoid handling wild birds. If you must do so, wear disposable gloves or use inverted plastic bags on your hands to avoid direct contact. Dead birds can be disposed of in a closed plastic bag in household trash or buried more than three feet under to prevent disease transmission to other animals.

Wildlife disease investigations can be inherently challenging and sometimes do not identify conclusive causes. The Pennsylvania Game Commission said it will promptly share any new findings with the public.