A commercial vaccine based on PCV2a and an experimental vaccine based on a variant mPCV2b are both effective in protecting pigs against challenge with a 2013 U.S. variant mPCV2b strain

Opriessnig, Tanja; Gerber, Priscilla Freitas; Xiao, Chao-Ting; Mogler, Mark; Halbur, Patrick G

doi:10.1016/j.vaccine.2013.11.010

Author(s)

Opriessnig, Tanja

Gerber, Priscilla Freitas

Xiao, Chao-Ting

Mogler, Mark

Halbur, Patrick G

Publication Date

2014

Abstract

During 2012 and 2013, an apparent increase in porcine circovirus associated disease occurred in the USA. A variant PCV2b strain designated mPCV2b was recovered from many of these cases. This raised concerns of a decrease in efficacy of commercially available PCV2 vaccines. The objective of this study was to compare the ability of a commercial PCV2a-based vaccine and an experimental mPCV2b-based vaccine to control mPCV2b-associated disease, lesions, and viremia in a challenge model. Twenty-six caesarian-derived, colostrum-deprived pigs were randomly assigned to one of four groups: (1) vaccinated with a commercial PCV2a-based vaccine and challenged (PCV2a-VAC; n= 7), (2) vaccinated with an experimental mPCV2b-based vaccine and challenged (mPCV2b; n= 7), (3) sham-vaccinated with saline and challenged (positive controls; n= 7), and (4) sham-vaccinated with saline without challenge (negative controls; n= 5). Vaccination was done on D0 and D14, challenge was done on D28 using a tissue homogenate containing PRRSV and mPCV2b and the experiment was terminated on D49. Among the challenged pigs, 47.6% (10/21) developed severe clinical disease and either died or had to be humanely euthanized between D39 and D48 (11-20 days after challenge). PCV2 viremia was almost completely absent in the vaccinated groups regardless of vaccine type except for two PCV2a-vaccinated pigs which had detectable PCV2 DNA levels on individual days after challenge. Microscopic lesions typical of PCV2 infection were limited to the positive control group which developed mild-to-severe lesions associated with low-to-abundant PCV2 antigen. Under the conditions of this study, PCV2 vaccines regardless of PCV2 type were effective against mPCV2b challenge.

Citation

Vaccine, 32(2), p. 230-237

ISSN

1873-2518

0264-410X

Link

https://hdl.handle.net/1959.11/21266

Language

en

Publisher

Elsevier Ltd

Title

A commercial vaccine based on PCV2a and an experimental vaccine based on a variant mPCV2b are both effective in protecting pigs against challenge with a 2013 U.S. variant mPCV2b strain

Type of document

Journal Article

Entity Type

Publication

Author(s)	Opriessnig, Tanja Gerber, Priscilla Freitas Xiao, Chao-Ting Mogler, Mark Halbur, Patrick G
Publication Date	2014
Abstract	During 2012 and 2013, an apparent increase in porcine circovirus associated disease occurred in the USA. A variant PCV2b strain designated mPCV2b was recovered from many of these cases. This raised concerns of a decrease in efficacy of commercially available PCV2 vaccines. The objective of this study was to compare the ability of a commercial PCV2a-based vaccine and an experimental mPCV2b-based vaccine to control mPCV2b-associated disease, lesions, and viremia in a challenge model. Twenty-six caesarian-derived, colostrum-deprived pigs were randomly assigned to one of four groups: (1) vaccinated with a commercial PCV2a-based vaccine and challenged (PCV2a-VAC; n= 7), (2) vaccinated with an experimental mPCV2b-based vaccine and challenged (mPCV2b; n= 7), (3) sham-vaccinated with saline and challenged (positive controls; n= 7), and (4) sham-vaccinated with saline without challenge (negative controls; n= 5). Vaccination was done on D0 and D14, challenge was done on D28 using a tissue homogenate containing PRRSV and mPCV2b and the experiment was terminated on D49. Among the challenged pigs, 47.6% (10/21) developed severe clinical disease and either died or had to be humanely euthanized between D39 and D48 (11-20 days after challenge). PCV2 viremia was almost completely absent in the vaccinated groups regardless of vaccine type except for two PCV2a-vaccinated pigs which had detectable PCV2 DNA levels on individual days after challenge. Microscopic lesions typical of PCV2 infection were limited to the positive control group which developed mild-to-severe lesions associated with low-to-abundant PCV2 antigen. Under the conditions of this study, PCV2 vaccines regardless of PCV2 type were effective against mPCV2b challenge.
Citation	Vaccine, 32(2), p. 230-237
ISSN	1873-2518 0264-410X
Link	https://hdl.handle.net/1959.11/21266
Language	en
Publisher	Elsevier Ltd
Title	A commercial vaccine based on PCV2a and an experimental vaccine based on a variant mPCV2b are both effective in protecting pigs against challenge with a 2013 U.S. variant mPCV2b strain
Type of document	Journal Article
Entity Type	Publication

A commercial vaccine based on PCV2a and an experimental vaccine based on a variant mPCV2b are both effective in protecting pigs against challenge with a 2013 U.S. variant mPCV2b strain

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