LANSING, Mich. (AP) – Michigan has lifted a statewide ban on poultry and waterfowl exhibitions after 30 days passed with no new cases of highly pathogenic avian influenza in domestic birds.

Bird shows can resume in the state, Michigan’s Department of Agriculture and Rural Development said in a statement.

The state halted poultry and waterfowl exhibitions May 10 as a precaution to protect against the spread of bird flu among poultry flocks.

“Even though the state has been able to reach this incredibly important benchmark, this does not mean the virus has left Michigan,” state Veterinarian Dr. Nora Wineland said in the statement. “HPAI continues to be detected in wild birds throughout the state, which is not unexpected as the virus is known to be carried by wild birds.”

Avian flu has been spreading across the United States, prompting farms to euthanize millions of birds. It can spread be spread from flock to flock, including wild birds, and through contact with infected poultry, equipment and caretakers.

When it banned the shows, the state said transporting poultry from different flocks to one location, such as a county fair, created a “significant risk.”

In 2015, avian flu prompted a similar ban on Michigan poultry shows, affecting nearly 4,000 youth who participate in poultry 4-H projects at county fairs throughout the state.

The latest outbreak of avian flu hit North America in December and has led to the culling of about 37 million chickens and turkeys on U.S. farms since February.

At least a dozen non-commercial backyard flocks in nine Michigan counties have been infected, impacting a total 870 birds, MLive.com reported earlier.

More information about avian flu can be found at Michigan.gov/birdflu.