FIG. 4.

Reactivities of several panels of sera in the CSFV lp-ELISA, performed as described in Materials and Methods. Negative field serum samples (n = 96) were randomly obtained from slaughtered adult pigs and were all tested negative in standard pestivirus ELISA. Pestivirus-positive but CSFV-negative serum samples (n = 96) were randomly obtained from slaughtered adult pigs. CSFV-positive field serum samples (n = 95) were obtained from an infected farm (VR) that was infected during the CSF epizootic in The Netherlands in 1997 to 1998.