Southern Chile’s important sheep farming industry is on the alert following the discovery of the Maedi visna virus in local livestock. As a preliminary step, the country’s Agricultural and Cattle Service (SAG) has placed stringent restrictions on the operations of nine Patagonian sheep farms. Several other farms are also expected to be affected by the restrictions, which seek to quarantine infected herds by preventing farmers from moving or selling diseased sheep.

SAG has also begun attempts to discover the extent of the virus’s spread in southern Chile. Recent examinations of randomly chosen sheep from across the region revealed the virus in 108 of the 2,273 animals examined by veterinary specialists. If this infection rate holds true throughout the estimated 2 million sheep in the far south, up to 6,000 sheep could be suffering from Maedi visna.  Clearly, identifying all the region’s infected sheep would present a huge organizational challenge to SAG and would require significant resources.

The virus is well-known in Europe, the US and Canada but has not been reported in any other Latin American country. Experts say, however, that this simply reflects the difficulty of identifying the disease, which produces similar symptoms to other sheep viruses.

By Steve Anderson, correspondent