Veterinary Medicine: Research and Reports (Feb 2020)
Vaccine Protection Against Experimental Challenge Infection with a PPV-27a Genotype Virus in Pregnant Gilts
Abstract
István Kiss,1 Edit Kovács,1 Zoltán Zádori,2 István Mészáros,2 Attila Cságola,1 Pál Bajnóczi,3 Preben Mortensen,4 Vilmos Palya1 1Ceva-Phylaxia Co. Ltd., Budapest, Hungary; 2Institute for Veterinary Medical Research, Centre for Agricultural Research, Budapest, Hungary; 3Prophyl Ltd., Mohács, Hungary; 4Ceva Animal Health, Libourne, FranceCorrespondence: István KissCeva-Phylaxia Co. Ltd., Szállás U. 5, Budapest H-1107, HungaryTel +36 1262 9505Fax +36010260 3889Email [email protected]/Introduction: Porcine parvovirus (PPV), the causative agent of severe reproductive failures in pigs, is present worldwide. The witnessed spread of the virulent 27a type PPV strains since its recognition raised concerns about the efficacy of the available commercial vaccines.Methods: To address this question, vaccinated pregnant gilts were challenged with a PPV-27a-like virus strain and parameters related to vaccine efficacy were compared.Results: The K22 vaccine strain of Parvoruvax® (PVX) was characterized as “Kresse-like” based on the epitope mapping data. Vaccination of the gilts induced a low level of antibody responses. Based on foetal mortality, the number of sows which had challenge virus-affected foetuses, the percent of PPV positive piglets/litters plus their PPV genome and viral load PVX outscored the other vaccinated groups.Conclusion: Stronger protection was provided by the “Kresse-like” K22 PPV strain-based vaccine than by the NADL-2 and NADL-like strain-based commercial vaccines against a PPV-27a cluster strain challenge. Vaccine-induced antibody levels as measured pre-challenge were not found to be an accurate indicator of protection.Keywords: PPV, K22 strain, efficacy, PPV-27a
