Migrating birds raise concerns as avian flu detections increase

As temperatures fall across North America, hundreds of bird species are moving south for the winter. The seasonal migration brings bursts of wildlife activity and growing concern among researchers tracking disease spread.

When birds migrate and congregate in large numbers, conditions become ripe for viruses to circulate more easily through wild populations, according to reporting from Georgia Public Broadcasting (GPB).

“Really across the continent, we’re starting to see pretty staggering increases in detections of highly pathogenic viruses,” said Becky Poulson, a researcher with the Southeastern Cooperative Wildlife Disease Study at the University of Georgia. Poulson told GPB that the increase in positive cases has been especially noticeable in November and December, when migration activity peaks.

Those viruses include strains of avian influenza, commonly known as bird flu. Data cited by GPB from the U.S. Department of Agriculture show detections of an H5 strain among wild birds in Georgia, signaling continued circulation of the virus in the state’s wildlife.

Poulson said the rising number of samples testing positive at the group’s Athens-based labs could indicate a shift in when infections typically spike during the year. Highly pathogenic avian influenza, often referred to as “high path,” has historically surged earlier in the migration season, but that pattern appears to be changing.

State agriculture officials say Georgia’s poultry industry is currently free from bird flu. The Georgia Department of Agriculture announced this month that commercial operations have stabilized following outbreaks earlier this year on farms in Elbert and Gordon counties, GPB reported.

While commercial poultry has recovered, the virus continues to affect wildlife. GPB reported that avian influenza has been fatal to an unknown number of Georgia’s wild birds this year, including black vultures, bald eagles and Canada geese.