Equine herpesvirus type 1 modified live virus vaccines: quo vaditis?
Infections of horses with equine herpesvirus type 1 (EHV-1) have garnered new attention over the last few years. Devastating outbreaks occurring worldwide, primarily of the neurologic form of the disease, have resulted in a reassessment of the control strategies, and particularly the prophylactic measures, that are necessary to keep the infection and spread of disease in check. Most of the available EHV-1 vaccines are based on preparations of inactivated virus, which are applied monovalently for prevention of EHV-1-caused abortion in pregnant mares or as part of multivalent vaccines to prevent respiratory disease. Despite the importance of an induction of cytotoxic immune responses for protection against EHV-1-induced disease, only two modified live virus vaccine preparations, which are both based on the avirulent EHV-1 strain RacH and were developed more than 40 years ago, are commercially available. Current efforts focus on exploiting the available infectious bacterial artificial chromosome clones of various EHV-1 strains to engineer a new generation of modified live virus vaccines. Both more efficient and long-lasting anti-EHV-1 immunity and delivery of immunogens of other pathogens are attempted and within immediate reach. The improvement of modified live virus vaccines will likely be a major focus of research in the future, and will hopefully help to more completely protect horses against one of the most important and devastating viral diseases.
Rosas
Cristina T
CT
Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA. ctr8@cornell.edu
Goodman
Laura B
LB
von Einem
Jens
J
Osterrieder
Nikolaus
N
D000818:Animals; D006566:Herpesviridae Infections / Q000276:immunology* / Q000517:prevention & control; D004861:Herpesvirus 1, Equid / Q000276:immunology*; D022283:Herpesvirus Vaccines / Q000276:immunology* / Q000627:therapeutic use; D006736:Horses; D014613:Vaccines, Attenuated / Q000276:immunology / Q000627:therapeutic use
D022283:Herpesvirus Vaccines; D014613:Vaccines, Attenuated