SANTIAGO, July 17 (Xinhua) -- Chilean animal hygiene authorities on Tuesday began to take steps to halt the spread of a Newcastle disease outbreak in marine birds in the city of Constitucion in central Chile.

    "We are implementing the strategy to ensure it does not spread from marine birds to domestic birds," said Carlos Montoya, the regional director of the Agriculture and Livestock Service.

    He said that Newcastle primarily strikes migratory birds, spreading via secretions, food, water and contaminated objects or cloth.

    The viral illness, which can kill its hosts, is characterized by drooping wings, panting, coughing, diarrhea and the partial or total loss of egg production.

    Montoya said that two mass vaccinations, 15 days apart, will be applied to the area's domestic birds such as chickens and ducks.

    On Monday, the authorities confirmed Newcastle in eight dead birds found in Constitution, 365 km south of Santiago. Hygiene inspectors collected another 27 dead birds in the area on Tuesday.

    The virus causes mild flu-like symptoms in humans.