Bulgaria reported an outbreak of avian influenza (bird flu) among poultry, according to the World Organization for Animal Health (WOAH), in October.

Reuters reported at the time that H5N1 was detected in a flock of 7,669 poultry in the Bulgarian village of Maritsa, resulting in the death of 764 birds.

Bulgaria’s veterinary services informed Greek authorities due to the countries’ close geographical and trade connections, and the importance of large bodies of water in northern Greece for Europe’s migratory birds. Since that time, Greece started regular checks at poultry farms.

Globally, the spread of bird flu has put governments on high alert as it impacts not only poultry but, in rare cases, can also transmit to humans.