Cases of bird flu have been detected in backyard chickens in Paraguay, authorities said Saturday.

The disease was found in the domesticated birds from the towns of Mariscal Estigarribia and Neuland in Mennonite farming areas, the National Animal Health and Quality Service (Senacsa) reported.

The potential cause being investigated is chickens having contact with infected migratory birds, the office said.

"The birds will be slaughtered to eliminate the source of infection," Senacsa said.

The disease has spread in Latin America in recent months and has triggered phytosanitary alerts.

Since late 2021, one of the worst global avian influenza outbreaks on record has seen tens of millions of poultry culled, mass wild bird die-offs and a rising number of infections among mammals in several countries.

Contact with sick birds can affect humans causing fever, cough and diarrhea among other symptoms.