| The intracerebral pathogenicity index could not be established since the virological analyses were unable to isolate the virus. |
| Although rare, cardiac dysrhythmias, heart failure, or intracerebral hemorrhage can occur. |
| Accompanying skull fractures are common, as are other types of bleeding such as epidural and intracerebral hematomas. |
| The classification of tissues shown in the table is based on titration of infectivity in mice by the intracerebral route. |
| Hypertension associated with cerebral infarction or intracerebral hemorrhage only rarely requires treatment. |
| Viral cultures are being carried out on embryonated eggs in order to isolate the virus and determine its intracerebral pathogenicity index. |
