Experimental infection of cattle, sheep and pigs with 'Hobi'-like pestivirus.

To date, limited information is available on the ability of 'Hobi'-like pestiviruses (putative bovine viral diarrhoea 3) to infect and cause disease in animal species traditionally affected by pestiviruses. In order to obtain new insights into host range and pathogenic potential of this atypical pestivirus, BVDV-seronegative calves (n=5), lambs (n=5) and piglets (n=5) were experimentally infected with the European 'Hobi'-like strain Italy-1/10-1, whereas two animals per species served as uninfected controls. Appearance of clinical signs, leukopenia, viremia, viral shedding and seroconversion were monitored for 28 days post-infection. Calves and lambs were successfully infected, displaying respiratory signs (nasal discharge), moderate hyperthermia and leukopenia, viremia and viral shedding through the nasal and faecal routes. Antibody responses were observed in both animal species by ELISA and virus neutralisation assays. In contrast, inoculated piglets did not display any clinical signs nor leukopenia and viral RNA was not detected in any biological samples. Nevertheless, the presence of detectable antibodies by virus neutralisation accounted for a successful, albeit limited infection of these animals.

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.