After a few dead seabirds were discovered on Rathlin Island, tests are underway.
The birds were found in Church Bay, which is the main harbour of the island off County Antrim coast.
Officials from the Agriculture Department said that two birds tested positive for Highly Pathogenic Avian Flu in Northern Ireland.
In April of this year, wild bird reports were introduced.
The largest outbreak of the disease ever recorded on these islands was caused by the HPAI strain. It began in November 2021.
This led to the culling and relocation of hundreds of thousands of birds in the UK.
According to the Royal Society for the Protection of Birds, there have been no confirmed cases of bird influenza at the West Light Seabird Centre in Rathlin Island.
A spokesperson stated that staff and volunteers "follow strict protocols and will continue being vigilant for dead or sick bird, reporting it to DAERA (Department of Agriculture, Environment and Rural Affairs), as required."
Scientists from the UK are currently investigating why this year's influenza outbreak was so deadly and what steps can be taken to prevent "any future spread of influenza with potential pandemic effects into humans."
The Avian Influenza Protection Area for Northern Ireland was removed on June 20, 2022.
A spokesperson for DAERA stated that there have been no cases of Highly Pathogenic Avian Influenza in poultry in Northern Ireland since February 2022.
"Since April's wild bird survey was recommenced, two submissions have been positive for HPAI H5N1.
"We also have concerns about the increase in seabird mortality on Rathlin Island."
"Testing is being done to determine if HPAI was the cause."
From backyard hobbyists to poultry farmers, flock keepers have been advised to adhere to strict biosecurity standards.
Several parts of England and Wales still feel the effects of the wild bird population crisis.
