Transmission of equine herpesvirus 2 to the mouse: characterization of a new laboratory infection model.

Intranasal inoculation of BALB/c mice with a recent clinical isolate of equine herpesvirus 2 (EHV-2 strain MR) produced a productive infection characterized by clinical signs, including weight-loss and conjunctivitis, but no mortality. Infectious virus was isolated from the lung, trachea and nasal turbinates with the highest titres present in lung tissue; EHV-2 neutralizing antibody was detected in the serum on day 21 post-inoculation. No infectious virus was detected in neural tissue, blood or lymphoid tissues. An EHV-2-specific nested PCR confirmed the presence of EHV-2 DNA in the respiratory tissues. In addition, EHV-2 DNA was detected in the trigeminal ganglia and olfactory bulbs from the first day after inoculation and these tissues remained positive for EHV-2 DNA for at least 30 days, by which time EHV-2 DNA had been cleared from all other tissues.