The challenges of classical swine fever control: Modified live and E2 subunit vaccines
Journal
Virus Research
Journal Volume
179
Journal Issue
1
Pages
1-11
Date Issued
2014
Author(s)
Abstract
Classical swine fever (CSF) is an economically important, highly contagious disease of swine worldwide. CSF is caused by classical swine fever virus (CSFV), and domestic pigs and wild boars are its only natural hosts. The two main strategies used to control CSF epidemic are systematic prophylactic vaccination and a non-vaccination stamping-out policy. This review compares the protective efficacy of the routinely used modified live vaccine (MLV) and E2 subunit vaccines and summarizes the factors that influence the efficacy of the vaccines and the challenges that both vaccines face to CSF control. Although MLV provide earlier and more complete protection than E2 subunit vaccines, it has the drawback of not allowing differentiation between infected and vaccinated animals (DIVA). The marker vaccine of E2 protein with companion discriminatory test to detect antibodies against Erns allows DIVA and is a promising strategy for future control and eradication of CSF. Maternal derived antibody (MDA) is the critical factor in impairing the efficacy of both MLV and E2 subunit vaccines, so the well-designed vaccination programs of sows and piglets should be considered together. Because of the antigen variation among various genotypes of CSFV, antibodies raised by either MLV or subunit vaccine neutralize genotypically homologous strains better than heterologous ones. However, although this is not a major concern for MLV as the induced immune responses can protect pigs against the challenge of various genotypes of CSFVs, it is critical for E2 subunit vaccines. It is thus necessary to evaluate whether the E2 subunit vaccine can completely protect against the current prevalent strains in the field. An ideal new generation of vaccine should be able to maintain the high protective efficiency of MLV and overcome the problem of antigenic variations while allowing for DIVA. © 2013 Elsevier B.V.
Subjects
Classical swine fever virus; E2 glycoprotein; E2 subunit vaccine; Modified live vaccine
SDGs
Other Subjects
E2 subunit vaccine; glycoprotein E2; live vaccine; marker vaccine; maternal antibody; subunit vaccine; unclassified drug; antigenic variation; cerebrospinal fluid; classical swine fever; domestic pig; drug efficacy; epidemic; genotype; human; immune response; natural host; nonhuman; priority journal; prophylaxis; review; sow (swine); vaccination; virus load; wild boar; Animalia; Classical swine fever virus; Suidae; Sus scrofa; Sus scrofa domestica; Classical swine fever virus; E2 glycoprotein; E2 subunit vaccine; Modified live vaccine; Animals; Antibodies, Viral; Classical Swine Fever; Classical swine fever virus; Swine; Vaccines, Subunit; Viral Vaccines
Type
review