Chilean authorities have thrown a security zone around an area where infectious salmon anemia (ISA) was detected at a production site belonging to a joint venture between Salmones Austral's Trusal and Nova Austral.

The outbreak at the Navarro 3 site bordering the Magallanes and Antarctic regions of Chile is currently affecting fish in two of the company's cages which together hold around 172,311 salmon, with an average weight of 430.4 grams.

While operations to remove fish from cages where positive tests were registered began on Monday the companies are required to carry out sanitary sampling tests on fish over the next seven days.