Latency and reactivation of bovine herpesvirus 1 (BHV-1) in goats and of caprine herpesvirus 1 (CapHV-1) in calves.

Bovine Herpesvirus 1 (BHV-1) and Caprine Herpesvirus 1 (CapHV-1) are related members of the herpesvirus family. Since their natural hosts are often kept in close contact with each other, concern was raised that a reservoir might be established in the heterologous host in addition to the homologous host. To investigate this possibility, cross-infection experiments with BHV-1 in goats and CapHV-1 in calves were performed. BHV-1 infected goats developed mild disease signs during acute infection, whereas CapHV-1 infection in calves took a subclinical course. However, virus excretion and antibody production were indicative of successful cross-infection of both BHV-1 and CapHV-1. Reactivation of BHV-1 was achieved in 5 out of 8 goats as demonstrated by recurrent virus excretion and rising antibody titers. In constrast CapHV-1 in calves could not be reactivated experimentally. Nevertheless, PCR revealed that both viruses established latency in the trigeminal ganglia of the heterologous host. Based on these results we conclude that goats should indeed be regarded as a potential BHV-1 reservoir, which must be considered during IBR eradication programs.