The mysterious illness that killed dozens of birds a day in some areas, causing their eyes to swell up and crust over and leading officials to ask residents to take down bird feeders and bird baths for fear they were helping the sickness to spread, appears to be over as quickly as it began—though without any clear answers. Officials in the mid-Atlantic, Midwest, and South regions where the ailment was killing birds have started telling residents they can put bird feeders back out. The number of calls about suffering birds has decreased, the Washington Post reports in a look at the Virginia cases. However, while officials have ruled out some causes—including bacteria, West Nile virus, avian influenza, pesticides, heavy metals, and, yes, coronaviruses—they have yet to figure out what was going on.
Connecticut officials also said residents can put bird feeders back out, the Hartford Courant reports; Kentucky and Indiana residents were told the same, per WVXU. As the mystery illness killed thousands of birds, officials worried about them gathering together at feeders, but the death toll has decreased enough that that is no longer a concern. Songbirds were mostly affected, and woodpeckers were as well. Scientists are continuing to investigate what might have caused the issue, including looking at whether cicadas—which also were in abundance in the area over the summer but are now gone—had anything to do with it. Residents are still advised to sanitize and disinfect their bird feeders and bird baths regularly, the National Wildlife Federation reports. (Read more birds stories.)