Infection was detected following permanent active surveillance carried out each year by the SENASA. No clinical cases of the disease were observed. In a population of 14.783 animals of different age groups, only 11 reacted positively to the ELISA test for detection of antibody against porcine reproductive and respiratory syndrome virus.
SENASA maintains a permanent surveillance in all farms in the area. Surveillance activities conducted at national level indicate the absence of the disease.
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Monday February 13, 2012/ OIE.
http://www.oie.int