Changes

===Laboratory Tests===

===Laboratory Tests===

The most commonly used tests are the ELISA or the indirect fluorescent antibody test. These tests measure IgG antibodies to PRRS virus. They cannot measure the level of immunity in an animal or predict whether the animal is a carrier. Titers are detected within 7-10 days after infection and can persist for up to 144 days. High titers may indicate recent exposure, and viral shedding may be occurring within the sampled population. Tests for PRRS virus include PCR, virus isolation, and immunohistochemistry. Recently, nucleic acid sequencing of the open reading frame 5 region of the virus has become commercially available, and has proved to be an excellent tool for epidemiologic investigations in the field to confirm similarity between isolates recovered from different sites.

The most commonly used tests are the ELISA or the indirect fluorescent antibody test. These tests measure IgG antibodies to PRRS virus. They cannot measure the level of immunity in an animal or predict whether the animal is a carrier. Titers are detected within 7-10 days after infection and can persist for up to 144 days. High titers may indicate recent exposure, and viral shedding may be occurring within the sampled population. Tests for PRRS virus include PCR, virus isolation, and immunohistochemistry. Recently, nucleic acid sequencing of the open reading frame 5 region of the virus has become commercially available, and has proved to be an excellent tool for epidemiologic investigations in the field to confirm similarity between isolates recovered from different sites.

==Control==

==Control==