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Porcine circovirus 2 (PCV2) remains a pervasive pathogen in global swine production despite nearly two decades of extensive vaccination. Current vaccines—highly effective at preventing clinical disease and reducing viral load—do not induce sterilizing immunity, allowing subclinical infections and continued viral circulation in many herds. Moreover, widespread piglet vaccination has altered PCV2 epidemiology, sometimes shifting infection to earlier ages or even to the intrauterine period. This persistence raises the question of whether PCV2 elimination, rather than control, is achievable under commercial conditions.

Diagnosis of PCV2 infection relies on compatible clinical signs, characteristic microscopic lesions, and detection of viral genome within affected tissues. Although PCV2 DNA is widespread in farm environments, such detection alone does not indicate disease. Subclinical infections still impair productivity, strengthening the rationale for minimizing viral circulation.


Proposal of vaccination program.

Protection against PCV2 depends on robust humoral and cellular immunity, but vaccine performance can be influenced by maternally derived antibodies, co-infections, and timing of administration. Single-dose piglet vaccination remains the standard, yet two-dose schedules can enhance immune responses and further reduce viremia—presence of virus in the blood—, especially under high infection pressure. Vaccination of sows and gilts complements piglet immunization by increasing passive immunity, reducing early-life infection, and mitigating vertical transmission. Boar vaccination may also contribute to reducing herd-level spread.

Mass vaccination strategies targeting all population groups could, in theory, reduce viral transmission to minimal levels and potentially eliminate PCV2, mirroring successful control programs for other swine pathogens. However, the only published whole-herd elimination attempt showed that viral disappearance was temporary as PCV2 re-emerged after cessation of vaccination. Achieving sustained elimination would require long-term, coordinated regional or national programs, strict biosecurity, and consistent vaccination compliance.

Although biological evidence supports the feasibility of elimination, its practical implementation faces economic, logistical, welfare, and organizational constraints. Improved vaccine formulations and needle-free technologies may facilitate mass vaccination in the future. Ultimately, PCV2 elimination is technically possible but depends on sustained human commitment, harmonized strategies, and industry-wide collaboration rather than on the virus or the pigs.