Maedi-Visna virus, detection

The Icelandic word maedi means shortness of breath; the disease was first described in Iceland in the 1950s. In addition to mouth breathing, other obvious symptoms include a dry cough, weak nasal secretions, and significant emaciation despite good feed intake, although these signs may only become visible up to years after infection. Visna describes the neurological form of the disease. Texel, dairy, and Cameroon sheep are particularly susceptible. The pathogen occurs globally. Transmission of the pathogen occurs through direct animal-to-animal contact and can be detected with a blood test for antibodies; approx. 30% of infected sheep fall ill. Treatments for this viral disease are not possible and vaccinations are not yet available. For herd reconstruction, the seropositive animals (blood sample) including their offspring must be euthanized.