CONTROL OF INFECTIOUS BOVINE-RHINOTRACHEITIS VIRUS-INFECTION

The control of infectious bovine rhinotracheitis (IBR) The control of infectious bovine rhinotracheitis (IBR) is now a major concern in the European Union in terms of cattle, semen and embryo trade. The eradication or control of this infection caused by bovine herpesvirus type 1 (BHV-1) has been initiated in several countries or regions. The establishment of wild-type or vaccinal BHV-1 strains in a latent state, following primary infection, reinfection or even after vaccination with a live attenuated or inactivated vaccine, is considered as a major obstacle to control programmes. Latency allows the persistence of BHV-1 infection even in closed herds. Morever, BHV-1 vaccination does not offer an epidemiological guarantee. In fact, current vaccines prevent clinical signs of the disease, but they are unable to prevent viral infection, latency, reactivation from latency and thus spread throughout a population. Therefore, new strategies of vaccination or new vaccines, as well as preventing clinical signs, should prevent the establishment of latency or at least reexcretion following reactivation. In addition, new vaccines should contain a serological marker to allow a distinction to be made between naturally infected and vaccinated animals. In this way, vaccination would be an important aid in the control and eradication of IBR. However, all strategies of control must take into account the risk that false negative animals may be present.