Feline viral rhinotracheitis: sites of virus replication and persistence in acutely and persistently infected cats

Abstract

In the acute stage of feline viral rhinotracheitis (FVR) infection virus was recovered most regularly and in largest amounts from turbinates, soft palate and tonsils; consistently but in smaller amounts from conjunctiva, mandibular lymph node and upper trachea; and irregularly from mandibular salivary gland, mid-and lower trachea and lung lobes. In a single cat virus was also recovered from liver and spleen, and in the same cat and one other, from trigeminal ganglia. In recovered, persistently infected, latent carrier cats, no virus was recovered from tissues taken post mortem from 19 non-stressed cats not shedding detectable virus in oropharyngeal secretions at the time of death. From one cat spontaneously shedding FVR virus, from seven shedding following corticosteroid treatment, and from two given corticosteroid but not detected as shedding virus at the time of sacrifice, FVR virus was recovered from one or more tissues. In nine of these 10 cats homogenised turbinates were virus positive, other tissues positive by homogenisation were soft palate (three cats), tonsil (three), oral mucosa (two) and tongue (two). A trigeminal ganglion ex-plant from the spontaneously shedding cat yielded FVR virus between 15 and 22, and 47 and 52 days after the culture was set up, and cell cocultures of olfactory bulb tissue from one cat shedding after corticosteroid treatment yielded virus from five and six to II and 15 days after initiation of culture.