Figure 5. Cerebrospinal fluid (CSF) parameter changes over time during human infection with variegated squirrel bornavirus 1 (VSBV-1) encephalitis. CSF analyses were performed at different time intervals (every 14 days or every 4–6 days) because the patients were seen in different hospitals. Patients had different durations of the disease (2–4 months), including a nonspecific prodromal phase during which no lumbar puncture was performed. A) Changes in CSF cell counts during the course of disease. An undulating lymphocytic pleocytosis is seen in patients 3 and 4, whereas in patient 1 only a mild cell count elevation is visible. In contrast, patient 2 shows a very prominent cell increase. B) Constantly increasing CSF protein levels during infection. A marked increase is demonstrated for patient 2. C) Lactate concentration changes in the CSF. Although pathologic levels decreased slowly over time in patients 1, 3, and 4, levels in patient 2 increased prominently.