Cidofovir does not prevent caprine herpesvirus type-1 neural latency in goats

Background: Cidofovir (CDV) is an acyclic nucleoside phosphonate that exhibits a potent antiviral activity against several DNA viruses. In previous studies, CDV has been shown to significantly reduce the clinical severity and the viral shedding in primary caprine herpesvirus type-1 (CpHV-1) infection in goats. CpHV-1 is an alpha-herpesvirus showing many biological similarities with human herpesvirus type-2 (HHV-2); therefore, studies conducted on the CpHV-1 goat model could provide useful information on the pathogenesis, therapy and prevention of HHV-2 infection in humans. Methods: CDV was administered to goats infected by vaginal route with CpHV-1. Real-time PCR was carried out on sacral ganglia from CpHV-1-infected goats to detect and quantify latent CpHV-1 DNA. Results: Viral DNA was variably found in all five pairs of sacral ganglia, with a more frequent involvement of the third and fourth pair. In CDV-treated goats, the amount of CpHV-1 DNA did not appear to be related either to the severity of the clinical signs or the titre of the virus shed during primary CpHV-1 infection. Conclusions: CDV failed to prevent CpHV-1 latency. Thus, vaginal CDV administration during primary herpesvirus infection, although providing immediate clinical benefits to the host might not influence the establishment of latency and, consequently, the rate of recurrent infections.