Differences in pathogenicity and antigenicity among hog cholera virus strains.

Area of Science:

• Veterinary Virology
• Immunology

Background:

• Hog cholera virus (HCV) causes significant disease in swine.
• Bovine viral diarrhea virus (BVDV) shares some antigenic properties with HCV, suggesting potential cross-neutralization.

Purpose of the Study:

• To investigate the antigenic relationship between HCV and BVDV using neutralization assays.
• To correlate the neutralization patterns with the pathogenicity of different HCV strains in pigs.

Main Methods:

• HCV strains were tested for neutralization by BVDV antiserum.
• The degree of neutralization was used to categorize HCV strains into Group H (poor neutralization) and Group B (good neutralization).
• Pigs were experimentally infected with strains from both groups, and clinical signs were monitored.

Main Results:

• HCV strains were successfully divided into Group H and Group B based on BVDV antiserum reactivity.
• Group H strains induced typical, acute hog cholera, while Group B strains caused a chronic illness.
• Pigs immunized with BVDV were protected against challenge with Group B HCV but succumbed to Group H HCV.

Conclusions:

• BVDV antiserum can differentiate between pathogenic groups of HCV.
• Antigenic differences between HCV strains, detectable by BVDV antiserum, correlate with distinct disease manifestations and protective immunity.