One of the first signs of trouble was a barking cough that resounded through a North Carolina farm in August 1998. Every pig in an operation of 2400 animals sickened, with symptoms similar to those caused by the human flu: high fever, poor appetite, and lethargy. Pregnant sows were hit hardest, and almost 10% aborted their litters, says veterinary virologist Gene Erickson of the Rollins Animal Disease Diagnostic Laboratory in Raleigh. Many piglets that survived in utero were later born small and weak, and some 50 sows died.
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