Strategies to broaden the cross-protective efficacy of vaccines against porcine reproductive and respiratory syndrome virus

Highlights

• Current vaccines are considered inadequately effective for control and eradication of PRRSV.

• The current PRRS vaccines do not provide optimal levels of heterologous protection, mainly due to the pronounced genetic diversity.

• This article reviews the vaccinology approaches that have been attempted to broaden the antigenic coverage of PRRS vaccines.

Abstract

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most economically important viral pathogens currently affecting swine production worldwide. Although PRRS vaccines have been commercially available for over 20 years, the available vaccines are considered inadequately effective for control and eradication of the virus. Major obstacles for the development of a highly effective PRRS vaccine include the highly variable nature of the viral genome, the viral ability to subvert the host immune system, and the incomplete understanding of the immune protection against PRRSV infection. This article summarizes the impediments for the development of a highly protective PRRS vaccine and reviews the vaccinology approaches that have been attempted to overcome one of the most formidable challenges, which is the substantial genetic variation among PRRSV isolates, to broaden the antigenic coverage of PRRS vaccines.

Key words: Heterologous protectionImmune evasion; Genetic diversity; DNA shuffling; Consensus immunogens; Chimeric virus.

Abstract published in Veterinary Microbiology, Volume 206, July 2017, Pages 29-34. https://doi.org/10.1016/j.vetmic.2016.09.014.