Exposure of Red Knots (Calidris canutus rufa) to Select Avian Pathogens; Patagonia, Argentina

As part of the shorebird surveillance, Red Knots (Calidris canutus rufa) were sampled in two Patagonian sites in Argentina, Rio Grande and San Antonio Oeste, during 2005–2006. Cloacal swabs and serum samples were collected from 156 birds and tested by virus isolation (Newcastle disease virus), polymerase chain reaction (PCR; avian influenza virus and Plasmodium/Hemoproteus), and for antibodies to St. Louis encephalitis virus. All test results were negative.