Pestivirus control programs: how far have we come and where are we going?

Area of Science:

• Veterinary Virology
• Animal Disease Control
• Livestock Management

Background:

• Classical swine fever (CSF) and bovine virus diarrhea (BVD) are significant global threats to the pig and cattle industries, respectively.
• Modified live vaccines (MLV) have proven effective for CSF control, including oral vaccination for wild boar.
• Bovine virus diarrhea virus (BVDV) is genetically diverse and spread by persistently infected (PI) calves, complicating conventional control.

Purpose of the Study:

• To review the effectiveness of vaccination and disease elimination strategies for CSF and BVD.
• To highlight the challenges posed by persistently infected animals in BVD control.
• To discuss current European approaches to BVD control.

Main Methods:

• Review of vaccination strategies, including modified live vaccines (MLV) for CSF.
• Analysis of disease transmission dynamics, focusing on persistently infected (PI) animals in BVD.
• Examination of European control programs for BVD, including elimination and optional vaccination.

Main Results:

• Systematic vaccination, particularly oral MLV, has been crucial for CSF elimination.
• Persistently infected (PI) animals are the primary reservoir for BVDV, undermining vaccination-only strategies.
• European BVD control relies on PI animal elimination, with or without optional vaccination.

Conclusions:

• Vaccination and stamping out are effective for CSF control and elimination.
• Elimination of persistently infected (PI) animals is essential for successful BVD control.
• Diverse strategies, including targeted elimination and optional vaccination, are employed for BVD management.