Studies on chronic herpetic keratitis--estimation of virus-harboring ganglion cells.

The reservoir site of herpes simplex virus (HSV) during the chronic phase of herpetic keratitis was confined to the trigeminal ganglion. Other ocular tissues, the cerebrum and the cerebellum were also examined and not found positive for the isolation of HSV by cocultivation with green monkey kidney cells 28-224 days after infection. The percentage of virus-harboring trigeminal ganglionic cells was estimated by determining the number of dispersed ganglionic cells needed to produce cytopathology of HSV on 50% of Vero cell monolayers. The percentage of infected ganglionic cells were calculated to range from 0.5% to 0.3% during this chronic period.